Draft California 2020 Integrated Report (303(d) List/305(b) Report)

Supporting Information

Regional Board 3 - Central Coast Region

Water Body Name: San Luis Obispo Creek (below Osos Street)
Water Body ID: CAR3102402119980828115513
Water Body Type: River & Stream
 
DECISION ID
109287
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Chlorpyrifos
Final Listing Decision: Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Delist from 303(d) list (TMDL required list)(2018)
Revision Status Revised
Reason for Delisting: Flaws in original listing
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the section 303(d) list under sections 4.1 and 4.6 of the Listing Policy. Under 4.1 of the Policy, a minimum of one line of evidence is needed to assess listing status. Under 4.6, a minimum of two lines of evidence are needed to assess listing status.

Sixteen lines of evidence are available in the administrative record to assess this pollutant. Note, four LOEs (47699, 47684, 47649 and 47721) summarize data from sediment pore water and the evaluation guideline is not relevant for this matrix. Therefore those LOEs were removed from and are not included in this decision.

The previous decision to add this water segment/pollutant combination to the Section 303(d) List was based on two water samples exceeding the evaluation guideline (Siepmann and Finlayson 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005) set to protect for aquatic life beneficial uses. However, one of those two samples was not a water sample and instead was a pore water, or interstitial water, sample and should not have been used as the basis of a decision (LOEs 16264, 16265).

One out of two water samples exceeded the evaluation guideline (Siepmann and Finlayson 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005) set to protect for aquatic life beneficial uses. This decision will not use nine samples collected from multiple LOEs (161448, 161432, 161566, 161569, 161626, 161568) because the laboratory’s method detection limit and reporting limits were greater than the evaluation guideline and the result was non-detect. Therefore, the results could not be quantified with the level of certainty required by the Listing Policy.

Zero out of 5 sediment samples (LOEs 57843, 57842, 151935, 151810) exceeded the aquatic life evaluation guideline (Amweg and Weston, 2007).

One water sample (pore water) (LOEs 16264, 16265) exceeded the Evaluation Guideline (Siepmann and Finlayson 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005) applied to protect for aquatic life beneficial uses. The other two pore water samples (LOEs 47699, 46684, 47649, 47721) will not be used in this assessment because the laboratory method detection limit was above the guideline and the result was non-detect. Therefore, the results could not be quantified with the level of certainty required by the Listing Policy. Additionally, there is no chlorpyrifos evaluation guideline specific to "sediment, interstitial water" (pore water). LOEs summarizing pore water results will not be the sole basis for any decision. The single pore water sample collected on April 1, 2004 contributed to the original listing during the 2010 listing cycle.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for removing this water segment-pollutant combination from the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

This conclusion is based on the staff findings that:

1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. One water sample exceeded the evaluation guideline for aquatic life beneficial uses and zero of five sediment samples exceed the aquatic life evaluation guideline. These meet the allowable frequency listed in Table 4.1 of the Listing Policy.
4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be removed from the section 303(d) List because applicable water quality standards for the pollutant are not being exceeded and the previous decision (2010) was in error because it included an exceedance in the pore water, a matrix for which there is no applicable evaluation guideline.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109287, Chlorpyrifos
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 16264
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Chlorpyrifos.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
  Final Data File used for assessment: SWAMP Sediment Chemistry Data from Region 3 Harbors, 2004
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
Objective/Criterion Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Evaluation Guideline: One hour average maximum concentration 0.025 ug/L as stated in Sipmann and Finlayson (2000).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109287, Chlorpyrifos
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 161378
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP SpecialStudies data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chlorpyrifos.
Data Reference: Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The freshwater criterion continuous concentration to protect aquatic organisms is 0.015 ug/L (Siepmann and Finlayson 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game (with minor corrections to significant figures as described in Beaulaurier et al., 2005).
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2018-01-17 and 2018-01-17
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109287, Chlorpyrifos
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 16265
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Chlorpyrifos.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
  Final Data File used for assessment: SWAMP Sediment Chemistry Data from Region 3 Harbors, 2004
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
Objective/Criterion Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Evaluation Guideline: One hour average maximum concentration 0.025 ug/L as stated in Sipmann and Finlayson (2000).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109287, Chlorpyrifos
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57843
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chlorpyrifos.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for chlorpyrifos is the median lethal concentration (LC50) of 1.77 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Amweg and Weston, 2007).
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109287, Chlorpyrifos
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57842
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chlorpyrifos.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for chlorpyrifos is the median lethal concentration (LC50) of 1.77 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Amweg and Weston, 2007).
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109287, Chlorpyrifos
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 161432
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Chlorpyrifos. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The freshwater criterion continuous concentration to protect aquatic organisms is 0.015 ug/L (Siepmann and Finlayson 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game (with minor corrections to significant figures as described in Beaulaurier et al., 2005).
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM).
Temporal Representation: Date for this waterbody was collected over the date range 2015-09-09 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109287, Chlorpyrifos
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 151810
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Chlorpyrifos .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for chlorpyrifos is the median lethal concentration (LC50) of 1.77 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Amweg and Weston, 2007).
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2013-05-30
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109287, Chlorpyrifos
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 151935
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Chlorpyrifos .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for chlorpyrifos is the median lethal concentration (LC50) of 1.77 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Amweg and Weston, 2007).
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2013-05-30
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109287, Chlorpyrifos
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 161626
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Chlorpyrifos. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The freshwater criterion continuous concentration to protect aquatic organisms is 0.015 ug/L (Siepmann and Finlayson 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game (with minor corrections to significant figures as described in Beaulaurier et al., 2005).
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Date for this waterbody was collected over the date range 2010-07-21 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109287, Chlorpyrifos
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 161566
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Chlorpyrifos. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The freshwater criterion continuous concentration to protect aquatic organisms is 0.015 ug/L (Siepmann and Finlayson 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game (with minor corrections to significant figures as described in Beaulaurier et al., 2005).
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Date for this waterbody was collected over the date range 2010-07-21 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109287, Chlorpyrifos
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 161568
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Chlorpyrifos. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The freshwater criterion continuous concentration to protect aquatic organisms is 0.015 ug/L (Siepmann and Finlayson 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game (with minor corrections to significant figures as described in Beaulaurier et al., 2005).
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM).
Temporal Representation: Date for this waterbody was collected over the date range 2015-09-09 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109287, Chlorpyrifos
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 161448
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Chlorpyrifos. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The freshwater criterion continuous concentration to protect aquatic organisms is 0.015 ug/L (Siepmann and Finlayson 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game (with minor corrections to significant figures as described in Beaulaurier et al., 2005).
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV).
Temporal Representation: Date for this waterbody was collected over the date range 2015-05-20 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109287, Chlorpyrifos
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 161471
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP SpecialStudies data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chlorpyrifos.
Data Reference: Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The freshwater criterion continuous concentration to protect aquatic organisms is 0.015 ug/L (Siepmann and Finlayson 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game (with minor corrections to significant figures as described in Beaulaurier et al., 2005).
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2018-01-17 and 2018-01-17
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109287, Chlorpyrifos
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 161569
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Chlorpyrifos. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The freshwater criterion continuous concentration to protect aquatic organisms is 0.015 ug/L (Siepmann and Finlayson 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game (with minor corrections to significant figures as described in Beaulaurier et al., 2005).
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV).
Temporal Representation: Date for this waterbody was collected over the date range 2015-05-20 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109287, Chlorpyrifos
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 16230
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Chlorpyrifos.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
  Final Data File used for assessment: SWAMP Sediment Chemistry Data from Region 3 Harbors, 2004
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
Objective/Criterion Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Evaluation Guideline: One hour average maximum concentration 0.025 ug/L as stated in Sipmann and Finlayson (2000).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/19/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109287, Chlorpyrifos
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 16229
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Chlorpyrifos.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
  Final Data File used for assessment: SWAMP Sediment Chemistry Data from Region 3 Harbors, 2004
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
Objective/Criterion Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Evaluation Guideline: One hour average maximum concentration 0.025 ug/L as stated in Sipmann and Finlayson (2000).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/19/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
 
DECISION ID
130244
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Fecal Coliform
Final Listing Decision: Delist from 303(d) list (being addressed by USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)(2018)
Revision Status Revised
Reason for Delisting: Applicable WQS attained; due to change in WQS
TMDL Name: San Luis Obispo Creek Pathogen
TMDL Project Code: 89
Date TMDL Approved by USEPA: 09/23/2005
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the CWA section 303(d) List under section 4 of the Listing Policy due to a change in water quality standards.

The State Water Boards Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California (the ISWEBE Plan) contains two bacteria water quality objectives applicable to the REC-1 beneficial use which were adopted on August 7, 2018: where the salinity level of a waterbody is equal to or less than 1 part per thousand 95 percent or more of the time, the E. coli bacteria objective applies; and where the salinity level of a waterbody is greater than 1 part per thousand 95 percent or more of the time, the Enterococci bacteria objective applies.

These objectives supersede the fecal coliform water quality objective for water contact recreation. Consequently, the fecal coliform objective for water contact recreation is no longer applicable to this waterbody and those LOEs have been removed from this decision. Therefore, this waterbody is being removed from the CWA section 303(d) List under section 4 of the Listing Policy due to a change in water quality standards.

However, eight lines of evidence (LOEs) are available in the administrative record to assess this pollutant and the non-contact recreation use. Therefore, this pollutant is being considered for placement on the CWA section 303(d) List under section 3.3 of the Listing Policy. Under section 3.3 a single line of evidence is necessary to assess listing status.

Thirty-two of the 274 samples exceed the water quality objective for non-contact recreation.

After review of the available data and information for the non-contact recreation beneficial use, RWQCB staff concludes that the water body-pollutant combination should not be placed on the CWA section 303(d) List because applicable water quality standards for the pollutant are not being exceeded.

In accordance with section 2.2 of the Policy, there is sufficient justification to place it in the Being Addressed portion of the 303(d) List because a TMDL has been completed and approved by RWQCB and USEPA, and is expected to result in attainment of the standard.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Thirty-two of the 274 samples exceed the water quality objective for non-contact recreation, and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy.
4. The San Luis Obispo Creek Pathogen TMDL has been approved by the USEPA on 9/23/2005.
5. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be removed from the CWA section 303(d) List under section 4 of the Listing Policy due to a change in water quality standards.

This water body pollutant combination should be placed in the Being Addressed portion of the CWA 303(d) List because a TMDL has been completed and approved by RWQCB and USEPA, and is expected to result in attainment of the standard.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 130244, Fecal Coliform
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 11607
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Santa Lucia (SantaLucia) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 15 samples exceed the criterion for Coliform, Fecal.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for non-contact water recreation uses (Section II.A.2. Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries, II.A.2.a) states the following: Fecal coliform concentration, based on a minimum of not less than five samples for any 30-day period, shall not exceed a log mean of 2000/100 ml, nor shall more than ten percent of samples collected during any 30-day period exceed 4000/100 ml.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/15/2002-3/19/2003. Santa Lucia Coast is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130244, Fecal Coliform
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 11791
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 58
Number of Exceedances: 1
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Coastal Confluences (CC) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 1 of 58 samples exceed the criterion for Coliform, Fecal.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for non-contact water recreation uses (Section II.A.2. Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries, II.A.2.a) states the following: Fecal coliform concentration, based on a minimum of not less than five samples for any 30-day period, shall not exceed a log mean of 2000/100 ml, nor shall more than ten percent of samples collected during any 30-day period exceed 4000/100 ml.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 4/24/2001-11/15/2006. CCAMP Coastal confluence monitoring is conducted monthly (with the exception of April 2003 - December 2003) and is ongoing.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130244, Fecal Coliform
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 81177
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 15
Number of Exceedances: 5
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (above Osos Street) to determine beneficial use support and results are as follows: 5 of 15 samples exceed the criterion for Coliform, Fecal.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for non-contact water recreation uses (Section II.A.2. Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries, II.A.2.a) states the following: Fecal coliform concentration, based on a minimum of not less than five samples for any 30-day period, shall not exceed a log mean of 2000/100 ml, nor shall more than ten percent of samples collected during any 30-day period exceed 4000/100 ml.
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (above Osos Street) was collected at 1 monitoring site [ 310SLM-San Luis Obispo Creek at Mission Plaza]
Temporal Representation: Data was collected over the time period 1/15/2002-3/19/2003.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 130244, Fecal Coliform
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 52007
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 40
Number of Exceedances: 1
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 1 of 40 samples exceed the criterion for Coliform, Fecal.
Data Reference: Coastal Confluences field data 2007-2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for non-contact water recreation uses (Section II.A.2. Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries, II.A.2.a) states the following: Fecal coliform concentration, based on a minimum of not less than five samples for any 30-day period, shall not exceed a log mean of 2000/100 ml, nor shall more than ten percent of samples collected during any 30-day period exceed 4000/100 ml.
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 1/18/2007-6/22/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 130244, Fecal Coliform
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 52008
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 24
Number of Exceedances: 7
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 7 of 24 samples exceed the criterion for Coliform, Fecal.
Data Reference: Santa Lucia Watershed Rotation field data 2009
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for non-contact water recreation uses (Section II.A.2. Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries, II.A.2.a) states the following: Fecal coliform concentration, based on a minimum of not less than five samples for any 30-day period, shall not exceed a log mean of 2000/100 ml, nor shall more than ten percent of samples collected during any 30-day period exceed 4000/100 ml.
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 2 monitoring sites [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road, 310SLM-San Luis Obispo Creek at Mission Plaza]
Temporal Representation: Data was collected over the time period 1/21/2009-12/16/2009.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 130244, Fecal Coliform
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 150085
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 98
Number of Exceedances: 5
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 5 of the 98 samples exceeded the water quality threshold for Coliform, Fecal. The water quality threshold is based on a 10% exceedance rate that is calculated for a 30-Day peroid.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for non-contact water recreation uses (Section 3.3.2. Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states the following: Fecal coliform concentration, based on a minimum of not less than five samples for any 30-day period, shall not exceed a log mean of 2000/100 mL, nor shall more than ten percent of samples collected during any 30-day period exceed 4000/100 mL.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): 310SLB
Temporal Representation: The samples were collected between the days of 2010-07-19 and 2018-12-06 .
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 130244, Fecal Coliform
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 150223
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 12
Number of Exceedances: 12
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 12 of the 12 samples exceeded the water quality threshold for Coliform, Fecal. The water quality threshold is based on a 10% exceedance rate that is calculated for a 30-Day peroid.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for non-contact water recreation uses (Section 3.3.2. Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states the following: Fecal coliform concentration, based on a minimum of not less than five samples for any 30-day period, shall not exceed a log mean of 2000/100 mL, nor shall more than ten percent of samples collected during any 30-day period exceed 4000/100 mL.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): 310SLM
Temporal Representation: The samples were collected between the days of 2015-01-29 and 2015-12-16 .
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 130244, Fecal Coliform
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 150221
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 12
Number of Exceedances: 1
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 1 of the 12 samples exceeded the water quality threshold for Coliform, Fecal. The water quality threshold is based on a 10% exceedance rate that is calculated for a 30-Day peroid.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for non-contact water recreation uses (Section 3.3.2. Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states the following: Fecal coliform concentration, based on a minimum of not less than five samples for any 30-day period, shall not exceed a log mean of 2000/100 mL, nor shall more than ten percent of samples collected during any 30-day period exceed 4000/100 mL.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): 310SLV
Temporal Representation: The samples were collected between the days of 2015-01-29 and 2015-12-16 .
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
125856
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Escherichia coli (E. coli)
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: No Source Analysis Available
Expected TMDL Completion Date: 2035
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: The State Water Board’s Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California (the ISWEBE Plan) contains two bacteria water quality objectives applicable to the REC-1 beneficial use, which were adopted on August 7, 2018. Because the salinity level of this waterbody is equal to or less than 1 part per thousand 95 percent or more of the time, the E. coli bacteria objective applies. This waterbody is being considered for removal from the CWA section 303(d) List under section 4.3 of the Listing Policy.

In accordance with section 6.1.5.3 of the Listing Policy, data should be representative of the critical timing that the pollutant is expected to impact the waterbody. E. coli populations may fluctuate substantially on a daily, seasonal, or yearly basis. Lacking constant inputs, indicator bacteria do not persist in the environment for a long period and effects are of relatively short duration. As a result, the historic levels of E. coli in the waterbody may be a poor indicator of current risks to human health, particularly when more recent data are available to sufficiently assess the water quality standard.

Additionally, water quality conditions in waterbodies may change as a result of management actions that have been implemented to address E. coli. Unrepresentative data may result in incorrectly placing or not placing a water body segment on the CWA section 303(d) List, which could result in the unnecessary expenditure of public resources or missing a human health problem. Historic lines of evidence for data collected prior to 2010 were evaluated pursuant to these considerations and were not used to assess water quality standards attainment because they do not meet the temporal representation requirements of section 6.1.5.3 of the Listing Policy.

All samples are evaluated using the statistical threshold value (STV) water quality objective for water contact recreation (ISWEBE, SWRCB 2019). The water quality objective states that the STV shall not be exceeded by more than 10 percent of the samples collected in a calendar month. Where there are more than one samples collected within any six-week period, a geomean of those samples is calculated and evaluated using the geomean water quality objective for water contact recreation (ISWEBE, SWRCB 2019).

Although eight lines of evidence are available in the administrative record to assess this pollutant, this decision is based upon evaluation of the E. coli data collected since 2010, which are most representative of existing conditions in the waterbody. Twenty-nine of the 114 samples collected since 2010 exceed the STV water quality objective (see LOEs 148211, 150349, 150150, and 150151) and this exceeds the allowable frequency listed in Table 4.2 of the Listing Policy. Note, two of the two geomeans exceed the geomean water quality objective (see LOE 148210) but this sample count is insufficient to determine a beneficial use support rating. The data were collected between 2010 and 2018 and represent a range of hydrologic conditions (both wet and dry years). This sample count of data collected since 2010 is adequate to determine that the beneficial use is not supported in accordance with the Listing Policy.
Note, there are three lines of evidence summarizing historic E. coli data (data collected prior to 2010) compared to the USEPAs Ambient Water Quality Criteria for Bacteria (USEPA, 1986). A total of 34 of the 89 historic samples exceed the USEPA criteria set to protect for water contact recreation (see LOEs 11849, 51989, and 51990). These data are not used for making this decision nor are they used in the final use support ratings.

After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the CWA section 303(d) List because applicable water quality standards for the pollutant are being exceeded.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. A total of 29 of the 114 samples collected since 2010 exceed the STV water quality objective (ISWEBE, SWRCB 2019) and this exceeds the allowable frequency listed in Table 4.2 of the Listing Policy.
4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) List because applicable water quality standards for the pollutant are being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation: Although eight lines of evidence are available in the administrative record to assess this pollutant, this decision is based upon evaluation of the E. coli data collected since 2010, which are most representative of existing conditions in the waterbody. Twenty-nine of the 114 samples collected since 2010 exceed the STV water quality objective (see LOEs 148211, 150349, 150150, and 150151) and this exceeds the allowable frequency listed in Table 4.2 of the Listing Policy. Note, two of the two geomeans exceed the geomean water quality objective (see LOE 148210) but this sample count is insufficient to determine a beneficial use support rating. The data were collected between 2010 and 2018 and represent a range of hydrologic conditions (both wet and dry years). This sample count of data collected since 2010 is adequate to determine that the beneficial use is not supported in accordance with the Listing Policy.
Note, there are three lines of evidence summarizing historic E. coli data (data collected prior to 2010) compared to the USEPAs Ambient Water Quality Criteria for Bacteria (USEPA, 1986). A total of 34 of the 89 historic samples exceed the USEPA criteria set to protect for water contact recreation (see LOEs 11849, 51989, and 51990). These data are not used for making this decision nor are they used in the final use support ratings.

After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the CWA section 303(d) List because applicable water quality standards for the pollutant are being exceeded.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. A total of 29 of the 114 samples collected since 2010 exceed the STV water quality objective (ISWEBE, SWRCB 2019) and this exceeds the allowable frequency listed in Table 4.2 of the Listing Policy.
4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 125856, Escherichia coli (E. coli)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 150151
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 4 of the 4 samples exceeded the Statistical Threshold Value (STV) water quality threshold for E. coli. The STV is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective applicable to all non-saline waters, is a Statistical Threshold Value (STV) of 320 cfu/100 mL. The applicable STV shall not be exceeded by more than 10 percent of the samples collected in a calendar month, calculated in a static manner (ISWEBE 2018).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): 310SLM
Temporal Representation: The samples were collected between the days of 2015-01-29 and 2015-07-23 .
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 125856, Escherichia coli (E. coli)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 148210
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 2
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek to determine beneficial use support and results are as follows: 2 of 2 samples exceed the criterion for Escherichia coli.
Data Reference: SWAMP FIB data: 1/4/2018--4/16/2018.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective applicable to all non-saline waters, is a geometric mean (GM) of E. coli not to exceed 100 cfu/100 mL. The waterbody GM shall not be greater than the applicable GM magnitude in any six-week interval, calculated weekly (ISWEBE 2018).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek was collected at 1 monitoring site [310SLB]
Temporal Representation: Data was collected on 2 sampling date(s): 04/03/2018 and 01/09/2018. CCAMP data is collected monthly and other samples associated with this project are included in another LOE for this site
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAPrP. QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 125856, Escherichia coli (E. coli)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 150349
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 96
Number of Exceedances: 23
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 23 of the 96 samples exceeded the Statistical Threshold Value (STV) water quality threshold for E. coli. The STV is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective applicable to all non-saline waters, is a Statistical Threshold Value (STV) of 320 cfu/100 mL. The applicable STV shall not be exceeded by more than 10 percent of the samples collected in a calendar month, calculated in a static manner (ISWEBE 2018).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): 310SLB
Temporal Representation: The samples were collected between the days of 2010-07-19 and 2018-12-06 .
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 125856, Escherichia coli (E. coli)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 148211
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 2
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek to determine beneficial use support and results are as follows: 1 of 2 samples exceed the criterion for Escherichia coli.
Data Reference: SWAMP FIB data: 1/4/2018--4/16/2018.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective applicable to all non-saline waters, is a Statistical Threshold Value (STV) of 320 cfu/100 mL. The applicable STV shall not be exceeded by more than 10 percent of the samples collected in a calendar month, calculated in a static manner (ISWEBE 2018).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek was collected at 1 monitoring site [310SLB]
Temporal Representation: Data was collected on 2 sampling date(s): 04/03/2018 and 01/09/2018. CCAMP data is collected monthly and other samples associated with this project are included in another LOE for this site
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAPrP. QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 125856, Escherichia coli (E. coli)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 11849
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 25
Number of Exceedances: 7
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Coastal Confluences (CC) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 7 of 25 samples exceed the criterion for Escherichia coli.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: USEPA Ambient Water Quality Criteria for Bacteria -1986.
Objective/Criterion Reference: Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002
 
Evaluation Guideline: Single sample maximum allowable density for E. coli in freshwater is 235 MPN/100mL (as stated in Table 4, page 15)
Guideline Reference: Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 1/10/2005-11/15/2006. CCAMP Coastal confluence monitoring is conducted monthly (with the exception of April 2003 - December 2003) and is ongoing.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 125856, Escherichia coli (E. coli)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51989
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 39
Number of Exceedances: 11
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 11 of 39 samples exceed the criterion for Escherichia coli.
Data Reference: Coastal Confluences field data 2007-2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: USEPA Ambient Water Quality Criteria for Bacteria -1986.
Objective/Criterion Reference: Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002
 
Evaluation Guideline: Single sample maximum allowable density for E. coli in freshwater is 235 MPN/100mL (as stated in Table 4, page 15 of the USEPA Ambient Water Quality Criteria for Bacteria -1986).
Guideline Reference: Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 1/18/2007-6/22/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 125856, Escherichia coli (E. coli)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51990
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 25
Number of Exceedances: 16
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 16 of 25 samples exceed the criterion for Escherichia coli.
Data Reference: Santa Lucia Watershed Rotation field data 2009
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: USEPA Ambient Water Quality Criteria for Bacteria -1986.
Objective/Criterion Reference: Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002
 
Evaluation Guideline: Single sample maximum allowable density for E. coli in freshwater is 235 MPN/100mL (as stated in Table 4, page 15 of the USEPA Ambient Water Quality Criteria for Bacteria -1986).
Guideline Reference: Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 2 monitoring sites [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road, 310SLM-San Luis Obispo Creek at Mission Plaza]
Temporal Representation: Data was collected over the time period 1/21/2009-12/16/2009.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 125856, Escherichia coli (E. coli)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 150150
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 12
Number of Exceedances: 1
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 1 of the 12 samples exceeded the Statistical Threshold Value (STV) water quality threshold for E. coli. The STV is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective applicable to all non-saline waters, is a Statistical Threshold Value (STV) of 320 cfu/100 mL. The applicable STV shall not be exceeded by more than 10 percent of the samples collected in a calendar month, calculated in a static manner (ISWEBE 2018).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): 310SLV
Temporal Representation: The samples were collected between the days of 2015-01-29 and 2015-12-16 .
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109308
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Oxygen, Dissolved
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: No Source Analysis Available
Expected TMDL Completion Date: 2035
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the section 303(d) List under section 4.2 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status.

Twenty-seven lines of evidence are available in the administrative record to assess this pollutant.

One hundred three of 410 samples exceed the cold freshwater habitat water quality objective (Basin Plan). Thirteen of 141 samples exceed the water quality objective for fish spawning (Basin Plan). One of the 410 samples exceed the water quality objective for warm freshwater habitat (Basin Plan). Note that there is no difference between samples fractions ‘dissolved’ and ‘total,’ therefore sample and exceedance counts will be summed for the purpose of this decision.

While the samples exceed the allowable frequency, data from 2010 to 2019 show a trend towards improved water quality conditions. However, we don't have sufficient data in accordance with section 4.10 of the Listing Policy, such as diurnal data or biological responses, to justify a delisting.

Previous decisions (pre-2020) included dissolved oxygen saturation LOEs as ancillary evidence. This decision will no longer include dissolved oxygen saturation and these LOEs will be retired next cycle.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. One hundred three of 410 samples exceed the cold freshwater habitat objective. This exceeds the allowable frequency listed in Table 4.2 of the Listing Policy.
4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) List because applicable water quality standards for the pollutant are being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109308, Oxygen, Dissolved
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 174547
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 105
Number of Exceedances: 8
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 8 of 105 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-19 and 2019-03-06
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109308, Oxygen, Dissolved
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 174253
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 17
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 3 of 17 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2016-07-13
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109308, Oxygen, Dissolved
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 174417
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2015-05-27 and 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109308, Oxygen, Dissolved
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 175799
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Fish Spawning
 
Number of Samples: 17
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 3 of 17 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2016-07-13
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109308, Oxygen, Dissolved
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 174591
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 14 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 5.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109308, Oxygen, Dissolved
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 174291
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Fish Spawning
 
Number of Samples: 105
Number of Exceedances: 8
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 8 of 105 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-19 and 2019-03-06
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109308, Oxygen, Dissolved
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 174576
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Fish Spawning
 
Number of Samples: 14
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 2 of 14 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109308, Oxygen, Dissolved
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 174872
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Fish Spawning
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2015-05-27 and 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109308, Oxygen, Dissolved
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 173999
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Dissolved Oxygen Study data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2012-07-13 and 2012-07-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109308, Oxygen, Dissolved
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 175259
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 105
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 105 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 5.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-19 and 2019-03-06
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109308, Oxygen, Dissolved
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 174280
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Fish Spawning
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Dissolved Oxygen Study data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2012-07-13 and 2012-07-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109308, Oxygen, Dissolved
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51912
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 41
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 41 samples exceed the criterion for Oxygen, Dissolved.
Data Reference: Coastal Confluences field data 2007-2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 1/18/2007-6/22/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109308, Oxygen, Dissolved
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 12717
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 59
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Coastal Confluences (CC) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 1 of 59 samples exceed the criterion for Oxygen, Dissolved.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin, Cold Water Habitat Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 4/24/2001-12/20/2006. CCAMP Coastal confluence monitoring is conducted monthly (with the exception of April 2003 - December 2003) and is ongoing.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109308, Oxygen, Dissolved
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 12752
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 13
Number of Exceedances: 7
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Diurnal Dissolved Oxygen Sampling (DO) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 7 of 13 samples exceed the criterion for Oxygen, Dissolved.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin, Cold Water Habitat Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 2 monitoring sites [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive, 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 7/3/2001-8/7/2006. Diurnal monitoring conducted in summer months at all CCAMP monitoring sites.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109308, Oxygen, Dissolved
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 12576
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Santa Lucia (SantaLucia) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 16 samples exceed the criterion for Oxygen, Dissolved.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin, Cold Water Habitat Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/15/2002-3/19/2003. Santa Lucia Coast is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109308, Oxygen, Dissolved
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 49223
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 115
Number of Exceedances: 81
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 81 of 115 samples exceed the criterion for Oxygen, Dissolved.
Data Reference: Nutrient Numeric Endpoint Study for San Luis Obispo Creek, July - August 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 5 monitoring sites [ RW_4- SLO Creek 75 meters upstream of City WWTP Outfall, RW_5- SLO Creek 50 meters downstream of City WWTP Outfall and Perfumo Creek, RW_8.2 - SLO Creek downstream of South Higuera St. Bridge, Station # 6 West of 101 Bridge, San_Luis_Bay_Drive_Bridge - San Luis Obispo Creek]
Temporal Representation: Data was collected over the time period 7/18/2010-8/16/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: There is no QAPP written specifically for this project. However, The City of San Luis Obispo Lab is certified by the State of California's Environmental Laboratory Accreditation Program (ELAP). In addition, calibration data for field probes was provided
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109308, Oxygen, Dissolved
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51913
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 25
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 1 of 25 samples exceed the criterion for Oxygen, Dissolved.
Data Reference: Santa Lucia Watershed Rotation field data 2009
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 2 monitoring sites [ 310SLM-San Luis Obispo Creek at Mission Plaza, 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/21/2009-12/16/2009.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109308, Oxygen, Dissolved
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51764
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 25
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 25 samples exceed the criterion for Oxygen, Dissolved.
Data Reference: Santa Lucia Watershed Rotation field data 2009
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 5.0 mg/l at any time (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 2 monitoring sites [ 310SLM-San Luis Obispo Creek at Mission Plaza, 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/21/2009-12/16/2009.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109308, Oxygen, Dissolved
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51763
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 41
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 41 samples exceed the criterion for Oxygen, Dissolved.
Data Reference: Coastal Confluences field data 2007-2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 5.0 mg/l at any time (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 1/18/2007-6/22/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109308, Oxygen, Dissolved
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 49241
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 115
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 115 samples exceed the criterion for Oxygen, Dissolved.
Data Reference: Nutrient Numeric Endpoint Study for San Luis Obispo Creek, July - August 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 5.0 mg/l at any time (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 5 monitoring sites [ RW_4- SLO Creek 75 meters upstream of City WWTP Outfall, RW_5- SLO Creek 50 meters downstream of City WWTP Outfall and Perfumo Creek, RW_8.2 - SLO Creek downstream of South Higuera St. Bridge, Station # 6 West of 101 Bridge, San_Luis_Bay_Drive_Bridge - San Luis Obispo Creek]
Temporal Representation: Data was collected over the time period 7/18/2010-8/16/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: There is no QAPP written specifically for this project. However, The City of San Luis Obispo Lab is certified by the State of California's Environmental Laboratory Accreditation Program (ELAP). In addition, calibration data for field probes was provided
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109308, Oxygen, Dissolved
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 12753
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 13
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Diurnal Dissolved Oxygen Sampling (DO) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 1 of 13 samples exceed the criterion for Oxygen, Dissolved.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin, General Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: For waters not mentioned by a specific beneficial use, dissolved oxygen concentration shall not be reduced below 5.0 mg/l at any time.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 2 monitoring sites [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive, 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 7/3/2001-8/7/2006. Diurnal monitoring conducted in summer months at all CCAMP monitoring sites.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109308, Oxygen, Dissolved
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 12718
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 59
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Coastal Confluences (CC) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 59 samples exceed the criterion for Oxygen, Dissolved.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin, General Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: For waters not mentioned by a specific beneficial use, dissolved oxygen concentration shall not be reduced below 5.0 mg/l at any time.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 4/24/2001-12/20/2006. CCAMP Coastal confluence monitoring is conducted monthly (with the exception of April 2003 - December 2003) and is ongoing.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109308, Oxygen, Dissolved
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 12591
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Santa Lucia (SantaLucia) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 16 samples exceed the criterion for Oxygen, Dissolved.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin, General Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: For waters not mentioned by a specific beneficial use, dissolved oxygen concentration shall not be reduced below 5.0 mg/l at any time.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/15/2002-3/19/2003. Santa Lucia Coast is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109308, Oxygen, Dissolved
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 174583
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 5.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2015-05-27 and 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109308, Oxygen, Dissolved
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 174594
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Dissolved Oxygen Study data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 5.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2012-07-13 and 2012-07-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109308, Oxygen, Dissolved
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 174111
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 2 of 14 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109308, Oxygen, Dissolved
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 174187
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 17
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 17 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 5.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2016-07-13
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
115464
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Nitrate
Final Listing Decision: Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)(2018)
Revision Status Revised
Sources: Agriculture | Municipal Point Sources | Natural Sources | Nonpoint Source | Other Urban Runoff
TMDL Name: San Luis Obispo Creek Nutrients
TMDL Project Code: 25
Date TMDL Approved by USEPA: 01/10/2007
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal on the CWA section 303(d) List under sections 2.2 and 4.1 of the Listing Policy. Under section 4.1 of the Policy, a minimum of one line of evidence is needed to assess listing status.

Forty-one lines of evidence are available in the administrative record to assess this pollutant. Lines of evidence for the pollutant name Nitrate and for the pollutant name Nitrogen, Nitrate are combined (same pollutant). Where the fraction is none, not recorded, or total, staff assumed that the fraction is dissolved, based on the analytical method. In these cases, sample and exceedance counts are summed for the purpose of making this decision.

The Agricultural Supply beneficial use is fully supported. Five of the 213 nitrate samples and zero of the 26 nitrate/nitrite samples exceed the water quality objectives for irrigation water (30 mg/L) and livestock watering (100 mg/L) respectively.

The Municipal and Domestic Supply beneficial use is not supported. A total of 227 of the 313 nitrate samples and 49 of the 143 nitrate/nitrite samples exceed this water quality objective.

The Aquatic Life beneficial uses are not supported. Since the 2010 Integrated Report assessment cycle, Central Coast Water Board staff assessed nitrate data using an evaluation guideline (Central Coast Region Technical Report, 2010) used to interpret the narrative water quality objective for biostimulatory substances, set to protect Cold and Warm Freshwater Habitat beneficial uses. A total of 213 of the 238 nitrate samples and 131 of the 143 nitrate/nitrite samples exceed this evaluation guideline. In addition, and in accordance with section 4.11 of the Listing Policy, the following evidence supports the conclusion that nitrate contributes to or causes a bio-stimulatory response in this waterbody segment.

1) Dissolved oxygen for this water body ranged from 3.6 mg/L to 13.6 mg/L, at times exceeding (falling below) the Cold Freshwater Habitat water quality objective of 7.0 mg/L but rarely exceeding the upper dissolved oxygen screening level of 13.0 mg/L (R3 NNE Technical Report.
2) Water column chlorophyll a concentrations ranged up to 31.1 ug/L, at times exceeding the screening threshold of 15 ug/L (R3 NNE Technical Report, 2010).
3) Using site-specific data from this waterbody, the California Benthic Biomass Predictor Tool, v. 13 (Tetratech, 2007) predicted
- the benthic algal contribution to oxygen deficit for sites in the lower reaches of this water body ranging from 3.90 mg/L to 4.17 mg/L. This exceeds the screening threshold for benthic algal contribution to oxygen deficit of 1.25 mg/L (R3 NNE Technical Report, 2010).
- the algae biomass ranging at sites from 70 g/m2 ash-free dry weight (AFDW) to 85 g/m2 AFDW. This exceeds the Cold Freshwater Habitat screening threshold for algae biomass of 60 grams/m2 and at one site the warm water screening threshold of 80 grams/m2 (Creager, et al., 2006).
- the benthic chlorophyll a concentrations ranging at sites from 174 mg/m2 to 212 mg/m2. This exceeds the Cold Freshwater Habitat screening threshold of 150 mg/m2, and at one site the Warm Freshwater Habitat screening threshold of 200 mg/m2 (Creager, et al., 2006).

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List. In accordance with section 2.2 of the Policy, there is sufficient justification to place it in the Being Addressed portion of the CWA 303(d) List because a TMDL has been completed and approved by RWQCB and USEPA, and is expected to result in attainment of the standard.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. A total of 227 of the 313 nitrate samples and 49 of the 143 nitrate/nitrite samples exceed the water quality objective for the Municipal and Domestic Supply beneficial use. These exceed the allowable frequency listed in Table 4.1 of the Listing Policy.
4. A total of 213 of the 238 nitrate samples and 131 of the 143 nitrate/nitrite samples exceed the evaluation guideline for Cold and Warm Freshwater Habitats. These exceed the allowable frequency listed in Table 4.1 of the Listing Policy and there is sufficient supporting evidence of eutrophication in this water segment in accordance with section 4.11 of the Listing Policy.
5. The San Luis Obispo Nitrate TMDL has been approved by USEPA on 01/10/2007.
6. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list (addressed by a USEPA approved TMDL) because applicable water quality standards for the pollutant are being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation: This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. A total of 227 of the 313 nitrate samples and 49 of the 143 nitrate/nitrite samples exceed the water quality objective for the Municipal and Domestic Supply beneficial use. These exceed the allowable frequency listed in Table 4.1 of the Listing Policy.
4. A total of 213 of the 238 nitrate samples and 131 of the 143 nitrate/nitrite samples exceed the evaluation guideline for Cold and Warm Freshwater Habitats. These exceed the allowable frequency listed in Table 4.1 of the Listing Policy and there is sufficient supporting evidence of eutrophication in this water segment in accordance with section 4.11 of the Listing Policy.
5. The San Luis Obispo Nitrate TMDL has been approved by USEPA on 01/10/2007.
6. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 52021
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 25
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 25 samples exceed the criterion for Nitrate as N.
Data Reference: Santa Lucia Watershed Rotation field data 2009
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines provided in Table 3-3 (Central Coast Waterboard Basin Plan, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). In Table 3-3 of the Basin Plan (page III-8), water quality guidelines state that severe problems may occur when nitrate exceeds 30 mg/L NO3 as N in irrigation supply water.
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 2 monitoring sites [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road, 310SLM-San Luis Obispo Creek at Mission Plaza]
Temporal Representation: Data was collected over the time period 1/21/2009-12/16/2009.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 52005
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 40
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 40 samples exceed the criterion for Nitrate as N.
Data Reference: Coastal Confluences field data 2007-2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines provided in Table 3-3 (Central Coast Waterboard Basin Plan, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). In Table 3-3 of the Basin Plan (page III-8), water quality guidelines state that severe problems may occur when nitrate exceeds 30 mg/L NO3 as N in irrigation supply water.
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 1/18/2007-6/22/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 10002
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 59
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Coastal Confluences (CC) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 59 samples exceed the criterion for Nitrate as N.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines provided in Table 3-3 (Central Coast Waterboard Basin Plan, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). In Table 3-3 of the Basin Plan (page III-8), water quality guidelines state that severe problems may occur when nitrate exceeds 30 mg/L NO3 as N in irrigation supply water.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 4/24/2001-12/20/2006. CCAMP Coastal confluence monitoring is conducted monthly (with the exception of April 2003 - December 2003) and is ongoing.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 48871
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 50
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 50 samples exceed the criterion for Nitrate as N.
Data Reference: Nutrient Numeric Endpoint Study for San Luis Obispo Creek, July - August 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines provided in Table 3-3 (Central Coast Waterboard Basin Plan, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). In Table 3-3 of the Basin Plan (page III-8), water quality guidelines state that severe problems may occur when nitrate exceeds 30 mg/L NO3 as N in irrigation supply water.
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 5 monitoring sites [ Station # 6 West of 101 Bridge, Station # 2 RW4:, Station # 4 RW5, Station # 5 RW 8.2, Station # 7 San Luis Bay Drive at Avila Beach Drive]
Temporal Representation: Data was collected over the time period 7/18/2010-8/16/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: There is no QAPP written specifically for this project. However, The City of SLO's Lab is certified with the Department of Public Health in accordance with the CWC section 13176. In addition QC data are provided with laboratory analyses and QC procedures
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 48873
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 50
Number of Exceedances: 50
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 50 of 50 samples exceed the criterion for Nitrate as N.
Data Reference: Nutrient Numeric Endpoint Study for San Luis Obispo Creek, July - August 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Technical Approach to Develop Nutrient Numeric Endpoints for California. U.S. EPA Region IX. State Water Resources Control Board. 68-C-02-108-To-111
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 5 monitoring sites [ Station # 6 West of 101 Bridge, Station # 2 RW4:, Station # 4 RW5, Station # 5 RW 8.2, Station # 7 San Luis Bay Drive at Avila Beach Drive]
Temporal Representation: Data was collected over the time period 7/18/2010-8/16/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: There is no QAPP written specifically for this project. However, The City of SLO's Lab is certified with the Department of Public Health in accordance with the CWC section 13176. In addition QC data are provided with laboratory analyses and QC procedures
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51759
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 40
Number of Exceedances: 40
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 40 of 40 samples exceed the criterion for Nitrate as N.
Data Reference: Coastal Confluences field data 2007-2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Technical Approach to Develop Nutrient Numeric Endpoints for California. U.S. EPA Region IX. State Water Resources Control Board. 68-C-02-108-To-111
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 1/18/2007-6/22/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51760
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 25
Number of Exceedances: 13
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 13 of 25 samples exceed the criterion for Nitrate as N.
Data Reference: Santa Lucia Watershed Rotation field data 2009
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Technical Approach to Develop Nutrient Numeric Endpoints for California. U.S. EPA Region IX. State Water Resources Control Board. 68-C-02-108-To-111
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 2 monitoring sites [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road, 310SLM-San Luis Obispo Creek at Mission Plaza]
Temporal Representation: Data was collected over the time period 1/21/2009-12/16/2009.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51968
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 25
Number of Exceedances: 11
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 11 of 25 samples exceed the criterion for Nitrate as N.
Data Reference: Santa Lucia Watershed Rotation field data 2009
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Maximum Contaminant Level for nitrate (NO3 as N) incorporated by reference in the Basin Plan is 10.0 mg/L (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 2 monitoring sites [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road, 310SLM-San Luis Obispo Creek at Mission Plaza]
Temporal Representation: Data was collected over the time period 1/21/2009-12/16/2009.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51967
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 40
Number of Exceedances: 30
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 30 of 40 samples exceed the criterion for Nitrate as N.
Data Reference: Coastal Confluences field data 2007-2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Maximum Contaminant Level for nitrate (NO3 as N) incorporated by reference in the Basin Plan is 10.0 mg/L (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 1/18/2007-6/22/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 10081
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 16
Number of Exceedances: 15
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Santa Lucia (SantaLucia) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 15 of 16 samples exceed the criterion for Nitrate as N.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin Objective for municipal and domestic supply uses of inland surface waters (Section II.A.2) states the following: waters shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Article 4, Chapter 15, Section 64435, Tables 2 and 3 as listed in Table 3-2. The maximum contaminant level listed in Table 3-2 (inorganic and fluoride concentrations not to be exceeded in domestic or municipal supply) for nitrate is 10.0 mg/L (NO3 as N).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
Objective/Criterion Reference: Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/15/2002-3/19/2003. Santa Lucia Coast is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 48882
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 50
Number of Exceedances: 40
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 40 of 50 samples exceed the criterion for Nitrate as N.
Data Reference: Nutrient Numeric Endpoint Study for San Luis Obispo Creek, July - August 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Maximum Contaminant Level for nitrate (NO3 as N) incorporated by reference in the Basin Plan is 10.0 mg/L (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 5 monitoring sites [ Station # 6 West of 101 Bridge, Station # 2 RW4:, Station # 4 RW5, Station # 5 RW 8.2, Station # 7 San Luis Bay Drive at Avila Beach Drive]
Temporal Representation: Data was collected over the time period 7/18/2010-8/16/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: There is no QAPP written specifically for this project. However, The City of SLO's Lab is certified with the Department of Public Health in accordance with the CWC section 13176. In addition QC data are provided with laboratory analyses and QC procedures
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 10003
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 59
Number of Exceedances: 41
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Coastal Confluences (CC) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 41 of 59 samples exceed the criterion for Nitrate as N.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin Objective for municipal and domestic supply uses of inland surface waters (Section II.A.2) states the following: waters shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Article 4, Chapter 15, Section 64435, Tables 2 and 3 as listed in Table 3-2. The maximum contaminant level listed in Table 3-2 (inorganic and fluoride concentrations not to be exceeded in domestic or municipal supply) for nitrate is 10.0 mg/L (NO3 as N).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
Objective/Criterion Reference: Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 4/24/2001-12/20/2006. CCAMP Coastal confluence monitoring is conducted monthly (with the exception of April 2003 - December 2003) and is ongoing.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 52046
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 25
Number of Exceedances: 13
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 13 of 25 samples exceed the criterion for Nitrate as N.
Data Reference: Santa Lucia Watershed Rotation field data 2009
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Technical Approach to Develop Nutrient Numeric Endpoints for California. U.S. EPA Region IX. State Water Resources Control Board. 68-C-02-108-To-111
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 2 monitoring sites [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road, 310SLM-San Luis Obispo Creek at Mission Plaza]
Temporal Representation: Data was collected over the time period 1/21/2009-12/16/2009.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 52045
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 40
Number of Exceedances: 40
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 40 of 40 samples exceed the criterion for Nitrate as N.
Data Reference: Coastal Confluences field data 2007-2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Technical Approach to Develop Nutrient Numeric Endpoints for California. U.S. EPA Region IX. State Water Resources Control Board. 68-C-02-108-To-111
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 1/18/2007-6/22/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 48884
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 50
Number of Exceedances: 50
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 50 of 50 samples exceed the criterion for Nitrate as N.
Data Reference: Nutrient Numeric Endpoint Study for San Luis Obispo Creek, July - August 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Technical Approach to Develop Nutrient Numeric Endpoints for California. U.S. EPA Region IX. State Water Resources Control Board. 68-C-02-108-To-111
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 5 monitoring sites [ Station # 6 West of 101 Bridge, Station # 2 RW4:, Station # 4 RW5, Station # 5 RW 8.2, Station # 7 San Luis Bay Drive at Avila Beach Drive]
Temporal Representation: Data was collected over the time period 7/18/2010-8/16/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: There is no QAPP written specifically for this project. However, The City of SLO's Lab is certified with the Department of Public Health in accordance with the CWC section 13176. In addition QC data are provided with laboratory analyses and QC procedures
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51911
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 26
Number of Exceedances: 14
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 14 of 26 samples exceed the criterion for Nitrate/Nitrite as N.
Data Reference: Santa Lucia Watershed Rotation field data 2009
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Technical Approach to Develop Nutrient Numeric Endpoints for California. U.S. EPA Region IX. State Water Resources Control Board. 68-C-02-108-To-111
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 2 monitoring sites [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road, 310SLM-San Luis Obispo Creek at Mission Plaza]
Temporal Representation: Data was collected over the time period 1/21/2009-12/16/2009.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 48899
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 50
Number of Exceedances: 50
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 50 of 50 samples exceed the criterion for Nitrate/Nitrite as N.
Data Reference: Nutrient Numeric Endpoint Study for San Luis Obispo Creek, July - August 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Technical Approach to Develop Nutrient Numeric Endpoints for California. U.S. EPA Region IX. State Water Resources Control Board. 68-C-02-108-To-111
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 5 monitoring sites [ Station # 6 West of 101 Bridge, Station # 2 RW4:, Station # 4 RW5, Station # 5 RW 8.2, Station # 7 San Luis Bay Drive at Avila Beach Drive]
Temporal Representation: Data was collected over the time period 7/18/2010-8/16/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: There is no QAPP written specifically for this project. However, The City of SLO's Lab is certified with the Department of Public Health in accordance with the CWC section 13176. In addition QC data are provided with laboratory analyses and QC procedures
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51761
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 41
Number of Exceedances: 41
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 41 of 41 samples exceed the criterion for Nitrate/Nitrite as N.
Data Reference: Coastal Confluences field data 2007-2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Technical Approach to Develop Nutrient Numeric Endpoints for California. U.S. EPA Region IX. State Water Resources Control Board. 68-C-02-108-To-111
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 1/18/2007-6/22/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 48912
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 50
Number of Exceedances: 40
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 40 of 50 samples exceed the criterion for Nitrate/Nitrite as N.
Data Reference: Nutrient Numeric Endpoint Study for San Luis Obispo Creek, July - August 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Maximum Contaminant Level for nitrate + nitrite (as N) that is incorporated by reference in the Basin Plan is 10.0 mg/L (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 5 monitoring sites [ Station # 6 West of 101 Bridge, Station # 2 RW4:, Station # 4 RW5, Station # 5 RW 8.2, Station # 7 San Luis Bay Drive at Avila Beach Drive]
Temporal Representation: Data was collected over the time period 7/18/2010-8/16/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: There is no QAPP written specifically for this project. However, The City of SLO's Lab is certified with the Department of Public Health in accordance with the CWC section 13176. In addition QC data are provided with laboratory analyses and QC procedures
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51969
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 41
Number of Exceedances: 31
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 31 of 41 samples exceed the criterion for Nitrate/Nitrite as N.
Data Reference: Coastal Confluences field data 2007-2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Maximum Contaminant Level for nitrate + nitrite (as N) that is incorporated by reference in the Basin Plan is 10.0 mg/L (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 1/18/2007-6/22/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51970
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 26
Number of Exceedances: 12
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 12 of 26 samples exceed the criterion for Nitrate/Nitrite as N.
Data Reference: Santa Lucia Watershed Rotation field data 2009
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Maximum Contaminant Level for nitrate + nitrite (as N) that is incorporated by reference in the Basin Plan is 10.0 mg/L (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 2 monitoring sites [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road, 310SLM-San Luis Obispo Creek at Mission Plaza]
Temporal Representation: Data was collected over the time period 1/21/2009-12/16/2009.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 52047
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 41
Number of Exceedances: 41
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 41 of 41 samples exceed the criterion for Nitrate/Nitrite as N.
Data Reference: Coastal Confluences field data 2007-2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Technical Approach to Develop Nutrient Numeric Endpoints for California. U.S. EPA Region IX. State Water Resources Control Board. 68-C-02-108-To-111
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 1/18/2007-6/22/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 171081
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 26
Number of Exceedances: 16
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 16 of 26 samples exceeded the water quality threshold for Nitrate + Nitrite as N.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All inland surface waters, enclosed bays, and estuaries shall not contain concentrations of inorganic chemicals in excess of the maximum contaminant levels for primary drinking water standards specified in California Code of Regulations, Title 22, Division 4, Chapter 15, Sections 64431 and 64433.2.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The California Maximum Contaminant Level for nitrate + nitrite (as N) is 10. mg/L (California Code of Regulations, Title 22).
Guideline Reference: California MCLs - Title 17 and Title 22 documents for 2019 - California Regulations Related to Drinking Water
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-19 and 2012-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 171271
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 26
Number of Exceedances: 26
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 26 of 26 samples exceeded the water quality threshold for Nitrate + Nitrite as N.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-19 and 2012-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 171057
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 26
Number of Exceedances: 26
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 26 of 26 samples exceeded the water quality threshold for Nitrate + Nitrite as N.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-19 and 2012-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 171322
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 26
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 26 samples exceeded the water quality threshold for Nitrate + Nitrite as N.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan and identified as the maximum concentration for nitrate + nitrite for livestock watering as 100 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-19 and 2012-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 172933
 
Pollutant: Nitrogen, Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 12 samples exceeded the water quality threshold for Nitrate as N.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 172291
 
Pollutant: Nitrogen, Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 99
Number of Exceedances: 98
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 98 of 99 samples exceeded the water quality threshold for Nitrate as N.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-19 and 2018-12-06
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 172776
 
Pollutant: Nitrogen, Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 99
Number of Exceedances: 98
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 98 of 99 samples exceeded the water quality threshold for Nitrate as N.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-19 and 2018-12-06
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 172632
 
Pollutant: Nitrogen, Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 12
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 12 of 12 samples exceeded the water quality threshold for Nitrate as N.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 173203
 
Pollutant: Nitrogen, Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 12 samples exceeded the water quality threshold for Nitrate as N.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 172739
 
Pollutant: Nitrogen, Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 12
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 5 of 12 samples exceeded the water quality threshold for Nitrate as N.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines listed in the Central Coast Basin Plan and identified as the level that severe problems may occur when nitrate exceeds 30 mg/L (NO3 as N) in irrigation supply water.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 172483
 
Pollutant: Nitrogen, Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 12
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 12 of 12 samples exceeded the water quality threshold for Nitrate as N.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 172615
 
Pollutant: Nitrogen, Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 12
Number of Exceedances: 12
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 12 of 12 samples exceeded the water quality threshold for Nitrate as N.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All inland surface waters, enclosed bays, and estuaries shall not contain concentrations of inorganic chemicals in excess of the maximum contaminant levels for primary drinking water standards specified in California Code of Regulations, Title 22, Division 4, Chapter 15, Sections 64431 and 64433.2.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The California Maximum Contaminant Level for nitrate (as N) 10.0 mg/L (California Code of Regulations, Title 22).
Guideline Reference: California MCLs - Title 17 and Title 22 documents for 2019 - California Regulations Related to Drinking Water
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 172784
 
Pollutant: Nitrogen, Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 12 samples exceeded the water quality threshold for Nitrate as N.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All inland surface waters, enclosed bays, and estuaries shall not contain concentrations of inorganic chemicals in excess of the maximum contaminant levels for primary drinking water standards specified in California Code of Regulations, Title 22, Division 4, Chapter 15, Sections 64431 and 64433.2.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The California Maximum Contaminant Level for nitrate (as N) 10.0 mg/L (California Code of Regulations, Title 22).
Guideline Reference: California MCLs - Title 17 and Title 22 documents for 2019 - California Regulations Related to Drinking Water
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 172002
 
Pollutant: Nitrogen, Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 99
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 99 samples exceeded the water quality threshold for Nitrate as N.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines listed in the Central Coast Basin Plan and identified as the level that severe problems may occur when nitrate exceeds 30 mg/L (NO3 as N) in irrigation supply water.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-19 and 2018-12-06
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 172484
 
Pollutant: Nitrogen, Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 99
Number of Exceedances: 78
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 78 of 99 samples exceeded the water quality threshold for Nitrate as N.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All inland surface waters, enclosed bays, and estuaries shall not contain concentrations of inorganic chemicals in excess of the maximum contaminant levels for primary drinking water standards specified in California Code of Regulations, Title 22, Division 4, Chapter 15, Sections 64431 and 64433.2.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The California Maximum Contaminant Level for nitrate (as N) 10.0 mg/L (California Code of Regulations, Title 22).
Guideline Reference: California MCLs - Title 17 and Title 22 documents for 2019 - California Regulations Related to Drinking Water
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-19 and 2018-12-06
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 172438
 
Pollutant: Nitrogen, Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 12 samples exceeded the water quality threshold for Nitrate as N.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines listed in the Central Coast Basin Plan and identified as the level that severe problems may occur when nitrate exceeds 30 mg/L (NO3 as N) in irrigation supply water.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 10068
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Santa Lucia (SantaLucia) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 16 samples exceed the criterion for Nitrate as N.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines provided in Table 3-3 (Central Coast Waterboard Basin Plan, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). In Table 3-3 of the Basin Plan (page III-8), water quality guidelines state that severe problems may occur when nitrate exceeds 30 mg/L NO3 as N in irrigation supply water.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/15/2002-3/19/2003. Santa Lucia Coast is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51762
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 26
Number of Exceedances: 14
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 14 of 26 samples exceed the criterion for Nitrate/Nitrite as N.
Data Reference: Santa Lucia Watershed Rotation field data 2009
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Technical Approach to Develop Nutrient Numeric Endpoints for California. U.S. EPA Region IX. State Water Resources Control Board. 68-C-02-108-To-111
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 2 monitoring sites [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road, 310SLM-San Luis Obispo Creek at Mission Plaza]
Temporal Representation: Data was collected over the time period 1/21/2009-12/16/2009.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 115464, Nitrate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 48914
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 50
Number of Exceedances: 50
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 50 of 50 samples exceed the criterion for Nitrate/Nitrite as N.
Data Reference: Nutrient Numeric Endpoint Study for San Luis Obispo Creek, July - August 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Technical Approach to Develop Nutrient Numeric Endpoints for California. U.S. EPA Region IX. State Water Resources Control Board. 68-C-02-108-To-111
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 5 monitoring sites [ Station # 6 West of 101 Bridge, Station # 2 RW4:, Station # 4 RW5, Station # 5 RW 8.2, Station # 7 San Luis Bay Drive at Avila Beach Drive]
Temporal Representation: Data was collected over the time period 7/18/2010-8/16/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: There is no QAPP written specifically for this project. However, The City of SLO's Lab is certified with the Department of Public Health in accordance with the CWC section 13176. In addition QC data are provided with laboratory analyses and QC procedures
QAPP Information Reference(s):
 
 
DECISION ID
128047
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Ammonia
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Twenty-eight lines of evidence (LOEs) are available in the administrative record to assess this pollutant.
Sample and exceedance counts for the lines of evidence with the fraction identified as “none” or “not recorded” are grouped together with those having the fraction “total”, based on the analytical method used. The following is a summary of the sample and exceedances for each beneficial use:

Based on LOEs summarizing un-ionized ammonia data, zero of the 174 samples exceed the water quality objective (Basin Plan) set to protect aquatic life.

Based on LOEs summarizing total ammonia data (‘nitrogen, ammonia’ and ‘nitrogen as ammonia’) zero of the 74 samples exceed the EPA's Aquatic Life Ambient Water Quality Criteria set to protect aquatic life.

Based on LOEs summarizing total ammonia data (‘nitrogen, ammonia’ and ‘nitrogen as ammonia’) zero of the 306 samples exceed the EPA's Lifetime Health advisory level set to protect municipal and domestic supply uses.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the samples exceed the water quality objectives and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 128047, Ammonia
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51949
 
Pollutant: Ammonia as Nitrogen
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 40
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 40 samples exceed the criterion for Ammonia As N, Total.
Data Reference: Coastal Confluences field data 2007-2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline: EPA's Lifetime Health advisory level for total ammonia is 30.0 mg/L as stated on page 8 of the 2006 edition of the drinking water standards and health advisories. This Advisory Level is defined as "the concentration of a chemical in drinking water that is not expected to cause any adverse noncarcinogenic effects for up to ten days of exposure."
Guideline Reference: 2006 edition of the drinking water standards and health advisories. EPA 822-R-03-013
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 1/18/2007-6/22/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 128047, Ammonia
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 183932
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Ammonia as N.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-02-26 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 128047, Ammonia
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 183871
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 60
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 60 samples exceeded the water quality threshold for Ammonia as N.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-08-12 and 2018-12-06
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 128047, Ammonia
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 184323
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 60
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 60 samples exceeded the water quality threshold for Ammonia as N.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-08-12 and 2018-12-06
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 128047, Ammonia
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 184154
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 94
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 94 samples exceeded the water quality threshold for Ammonia as N.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: EPA's Lifetime Health advisory level for total ammonia is 30.0 mg/L as stated on page 8 of the 2012 edition of the drinking water standards and health advisories. This Advisory Level is defined as 'the concentration of a chemical in drinking water that is not expected to cause any adverse noncarcinogenic effects for a lifetime of exposure.'
Guideline Reference: 2018 Edition of the Drinking Water Standards and Health Advisories
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-19 and 2018-12-06
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 128047, Ammonia
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 183891
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 11
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 11 samples exceeded the water quality threshold for Ammonia as N.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: EPA's Lifetime Health advisory level for total ammonia is 30.0 mg/L as stated on page 8 of the 2012 edition of the drinking water standards and health advisories. This Advisory Level is defined as 'the concentration of a chemical in drinking water that is not expected to cause any adverse noncarcinogenic effects for a lifetime of exposure.'
Guideline Reference: 2018 Edition of the Drinking Water Standards and Health Advisories
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 128047, Ammonia
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 184069
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Ammonia as N.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-02-26 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 128047, Ammonia
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 184051
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Ammonia as N.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-02-26 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 128047, Ammonia
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 52059
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 23
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 23 samples exceed the criterion for Ammonia as N, Unionized.
Data Reference: Santa Lucia Watershed Rotation field data 2009
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin General Objective, Chapter III, Section II.A.2 (General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries) states that the discharge of wastes shall not cause concentrations of unionized ammonia (NH3) to exceed 0.025 mg/l (as N) in receiving waters (page III-4) .
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 2 monitoring sites [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road, 310SLM-San Luis Obispo Creek at Mission Plaza]
Temporal Representation: Data was collected over the time period 1/21/2009-12/16/2009.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 128047, Ammonia
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 9985
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 58
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Coastal Confluences (CC) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 58 samples exceed the criterion for Ammonia as N, Unionized.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin General Objective, Chapter III, Section II.A.2 (General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries) states that the discharge of wastes shall not cause concentrations of unionized ammonia (NH3) to exceed 0.025 mg/l (as N) in receiving waters (page III-4) .
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 4/24/2001-12/20/2006. CCAMP Coastal confluence monitoring is conducted monthly (with the exception of April 2003 - December 2003) and is ongoing.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 128047, Ammonia
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 52058
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 38
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 38 samples exceed the criterion for Ammonia as N, Unionized.
Data Reference: Coastal Confluences field data 2007-2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin General Objective, Chapter III, Section II.A.2 (General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries) states that the discharge of wastes shall not cause concentrations of unionized ammonia (NH3) to exceed 0.025 mg/l (as N) in receiving waters (page III-4) .
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 1/18/2007-6/22/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 128047, Ammonia
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 10052
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Santa Lucia (SantaLucia) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 16 samples exceed the criterion for Ammonia as N, Unionized.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin General Objective, Chapter III, Section II.A.2 (General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries) states that the discharge of wastes shall not cause concentrations of unionized ammonia (NH3) to exceed 0.025 mg/l (as N) in receiving waters (page III-4) .
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/15/2002-3/19/2003. Santa Lucia Coast is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 128047, Ammonia
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 52027
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 38
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 38 samples exceed the criterion for Ammonia as N, Unionized.
Data Reference: Coastal Confluences field data 2007-2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin General Objective, Chapter III, Section II.A.2 (General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries) states that the discharge of wastes shall not cause concentrations of unionized ammonia (NH3) to exceed 0.025 mg/l (as N) in receiving waters (page III-4).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 1/18/2007-6/22/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 128047, Ammonia
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 52028
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 23
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 23 samples exceed the criterion for Ammonia as N, Unionized.
Data Reference: Santa Lucia Watershed Rotation field data 2009
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin General Objective, Chapter III, Section II.A.2 (General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries) states that the discharge of wastes shall not cause concentrations of unionized ammonia (NH3) to exceed 0.025 mg/l (as N) in receiving waters (page III-4).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 2 monitoring sites [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road, 310SLM-San Luis Obispo Creek at Mission Plaza]
Temporal Representation: Data was collected over the time period 1/21/2009-12/16/2009.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 128047, Ammonia
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 10065
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Santa Lucia (SantaLucia) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 16 samples exceed the criterion for Ammonia as N, Unionized.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin General Objective, Chapter III, Section II.A.2 (General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries) states that the discharge of wastes shall not cause concentrations of unionized ammonia (NH3) to exceed 0.025 mg/l (as N) in receiving waters (page III-4) .
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/15/2002-3/19/2003. Santa Lucia Coast is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 128047, Ammonia
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 9986
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 58
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Coastal Confluences (CC) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 58 samples exceed the criterion for Ammonia as N, Unionized.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin General Objective, Chapter III, Section II.A.2 (General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries) states that the discharge of wastes shall not cause concentrations of unionized ammonia (NH3) to exceed 0.025 mg/l (as N) in receiving waters (page III-4) .
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 4/24/2001-12/20/2006. CCAMP Coastal confluence monitoring is conducted monthly (with the exception of April 2003 - December 2003) and is ongoing.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 128047, Ammonia
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 184050
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Ammonia as N.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-02-26 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 128047, Ammonia
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51950
 
Pollutant: Ammonia as Nitrogen
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 25
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 25 samples exceed the criterion for Ammonia As N, Total.
Data Reference: Santa Lucia Watershed Rotation field data 2009
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline: EPA's Lifetime Health advisory level for total ammonia is 30.0 mg/L as stated on page 8 of the 2006 edition of the drinking water standards and health advisories. This Advisory Level is defined as "the concentration of a chemical in drinking water that is not expected to cause any adverse noncarcinogenic effects for up to ten days of exposure."
Guideline Reference: 2006 edition of the drinking water standards and health advisories. EPA 822-R-03-013
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 2 monitoring sites [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road, 310SLM-San Luis Obispo Creek at Mission Plaza]
Temporal Representation: Data was collected over the time period 1/21/2009-12/16/2009.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 128047, Ammonia
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 10051
 
Pollutant: Ammonia as Nitrogen
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Santa Lucia (SantaLucia) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 16 samples exceed the criterion for Ammonia as N, Total.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: USEPA Health Advisory 2006 Edition of the Drinking Water Standards and Health Advisories (EPA 822-R-06-013, 2006).
Objective/Criterion Reference: 2006 edition of the drinking water standards and health advisories. EPA 822-R-03-013
 
Evaluation Guideline: EPA's Lifetime Health advisory level for total ammonia is 30.0 mg/L as stated on page 8 of the 2006 edition of the drinking water standards and health advisories. This Advisory Level is defined as "the concentration of a chemical in drinking water that is not expected to cause any adverse noncarcinogenic effects for up to ten days of exposure."
Guideline Reference: 2006 edition of the drinking water standards and health advisories. EPA 822-R-03-013
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/15/2002-3/19/2003. Santa Lucia Coast is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 128047, Ammonia
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 48863
 
Pollutant: Ammonia as Nitrogen
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 50
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 50 samples exceed the criterion for Ammonia as N, Total.
Data Reference: Nutrient Numeric Endpoint Study for San Luis Obispo Creek, July - August 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline: EPA's Lifetime Health advisory level for total ammonia is 30.0 mg/L as stated on page 8 of the 2006 edition of the drinking water standards and health advisories. This Advisory Level is defined as "the concentration of a chemical in drinking water that is not expected to cause any adverse noncarcinogenic effects for up to ten days of exposure."
Guideline Reference: 2006 edition of the drinking water standards and health advisories. EPA 822-R-03-013
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 5 monitoring sites [ Station # 6 West of 101 Bridge, Station # 2 RW4:, Station # 4 RW5, Station # 5 RW 8.2, Station # 7 San Luis Bay Drive at Avila Beach Drive]
Temporal Representation: Data was collected over the time period 7/18/2010-8/16/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: There is no QAPP written specifically for this project. However, The City of SLO's Lab is certified with the Department of Public Health in accordance with the CWC section 13176. In addition QC data are provided with laboratory analyses and QC procedures
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 128047, Ammonia
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 9984
 
Pollutant: Ammonia as Nitrogen
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 59
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Coastal Confluences (CC) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 59 samples exceed the criterion for Ammonia as N, Total.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: USEPA Health Advisory 2006 Edition of the Drinking Water Standards and Health Advisories (EPA 822-R-06-013, 2006).
Objective/Criterion Reference: 2006 edition of the drinking water standards and health advisories. EPA 822-R-03-013
 
Evaluation Guideline: EPA's Lifetime Health advisory level for total ammonia is 30.0 mg/L as stated on page 8 of the 2006 edition of the drinking water standards and health advisories. This Advisory Level is defined as "the concentration of a chemical in drinking water that is not expected to cause any adverse noncarcinogenic effects for up to ten days of exposure."
Guideline Reference: 2006 edition of the drinking water standards and health advisories. EPA 822-R-03-013
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 4/24/2001-12/20/2006. CCAMP Coastal confluence monitoring is conducted monthly (with the exception of April 2003 - December 2003) and is ongoing.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 128047, Ammonia
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 219447
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the water quality threshold for Ammonia as N, Unionized. Although a total of 11 samples were collected, 7 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin General Objective, Chapter 3, Section 3.3.2 (Objectives for all Inland Surface Waters, Enclosed Bays, and Estuaries) states that the discharge of wastes shall not cause concentrations of unionized ammonia (NH3) to exceed 0.025 mg/L (as N) in receiving waters (page 32).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV).
Temporal Representation: Data for this waterbody was collected over the date range 2015-01-29 to 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 128047, Ammonia
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 219410
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 36
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 36 samples exceeded the water quality threshold for Ammonia as N, Unionized. Although a total of 95 samples were collected, 59 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin General Objective, Chapter 3, Section 3.3.2 (Objectives for all Inland Surface Waters, Enclosed Bays, and Estuaries) states that the discharge of wastes shall not cause concentrations of unionized ammonia (NH3) to exceed 0.025 mg/L (as N) in receiving waters (page 32).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Data for this waterbody was collected over the date range 2010-07-19 to 2018-12-06
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 128047, Ammonia
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 219477
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the water quality threshold for Ammonia as N, Unionized. Although a total of 11 samples were collected, 7 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin General Objective, Chapter 3, Section 3.3.2 (Objectives for all Inland Surface Waters, Enclosed Bays, and Estuaries) states that the discharge of wastes shall not cause concentrations of unionized ammonia (NH3) to exceed 0.025 mg/L (as N) in receiving waters (page 32).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV).
Temporal Representation: Data for this waterbody was collected over the date range 2015-01-29 to 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 128047, Ammonia
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 219482
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 36
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 36 samples exceeded the water quality threshold for Ammonia as N, Unionized. Although a total of 95 samples were collected, 59 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin General Objective, Chapter 3, Section 3.3.2 (Objectives for all Inland Surface Waters, Enclosed Bays, and Estuaries) states that the discharge of wastes shall not cause concentrations of unionized ammonia (NH3) to exceed 0.025 mg/L (as N) in receiving waters (page 32).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Data for this waterbody was collected over the date range 2010-07-19 to 2018-12-06
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 128047, Ammonia
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 219464
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Ammonia as N, Unionized. Although a total of 11 samples were collected, 11 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin General Objective, Chapter 3, Section 3.3.2 (Objectives for all Inland Surface Waters, Enclosed Bays, and Estuaries) states that the discharge of wastes shall not cause concentrations of unionized ammonia (NH3) to exceed 0.025 mg/L (as N) in receiving waters (page 32).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM).
Temporal Representation: Date for this waterbody was collected over the date range 2015-01-29 to 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 128047, Ammonia
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 219590
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Ammonia as N, Unionized. Although a total of 11 samples were collected, 11 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin General Objective, Chapter 3, Section 3.3.2 (Objectives for all Inland Surface Waters, Enclosed Bays, and Estuaries) states that the discharge of wastes shall not cause concentrations of unionized ammonia (NH3) to exceed 0.025 mg/L (as N) in receiving waters (page 32).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM).
Temporal Representation: Date for this waterbody was collected over the date range 2015-01-29 to 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 128047, Ammonia
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 184410
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 11
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 11 samples exceeded the water quality threshold for Ammonia as N.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: EPA's Lifetime Health advisory level for total ammonia is 30.0 mg/L as stated on page 8 of the 2012 edition of the drinking water standards and health advisories. This Advisory Level is defined as 'the concentration of a chemical in drinking water that is not expected to cause any adverse noncarcinogenic effects for a lifetime of exposure.'
Guideline Reference: 2018 Edition of the Drinking Water Standards and Health Advisories
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109279
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Anthracene
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) list under section 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment. The pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the Section 303(d) list.

Six lines of evidence (LOEs) are available in the administrative record to assess this pollutant.
Sample and exceedance counts for the lines of evidence with the fraction identified as “none” or “not recorded” are grouped together with those having the fraction “total”, based on the analytical method used. The following is a summary of the sample and exceedances for each beneficial use:

Zero of four sediment samples exceed the aquatic life evaluation guideline. This sample size is insufficient to determine an applicable beneficial use support rating with the power and confidence of the Listing Policy. In accordance with Table 3.1 of the Listing Policy, a minimum of 16 samples is needed to determine if a beneficial use is fully supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:

1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero samples exceed the evaluation guideline and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109279, Anthracene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 15606
 
Pollutant: Anthracene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Anthracene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for anthracene is 845 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109279, Anthracene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 15623
 
Pollutant: Anthracene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Anthracene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for anthracene is 845 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109279, Anthracene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 15610
 
Pollutant: Anthracene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Anthracene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for anthracene is 845 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109279, Anthracene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 15605
 
Pollutant: Anthracene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Anthracene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for anthracene is 845 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109279, Anthracene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 151249
 
Pollutant: Anthracene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Anthracene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Anthrazene from MacDonald et al., 2000a which states that the probable effect concentration for Anthrazene is 845 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109279, Anthracene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 151187
 
Pollutant: Anthracene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Anthracene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Anthrazene from MacDonald et al., 2000a which states that the probable effect concentration for Anthrazene is 845 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109281
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Arsenic
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the Clean Water Act (CWA) section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment. The pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the CWA section 303(d) List.

A total of 14 lines of evidence are available in the administrative record to assess this pollutant. Sample and exceedance counts for the lines of evidence with the fraction identified as ''none'' or ''not recorded'' are grouped together with those having the fraction ''total'', based on the analytical method used. For the water matrix, a total of zero of 14 samples exceed the water quality objective for the agricultural supply beneficial use and zero of 14 samples exceed the evaluation guideline for the municipal and domestic supply beneficial use. For the sediment matrix, a total of zero of 10 samples exceed the evaluation guideline for the cold freshwater habitat beneficial use and zero of 10 samples exceed the evaluation guideline for the warm freshwater habitat beneficial use. These data are insufficient to determine the applicable beneficial use support rating with the power and confidence required by the Listing Policy.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. For the water matrix, a total of zero of 14 samples exceed the water quality objective for the agricultural supply beneficial use and zero of 14 samples exceed the evaluation guideline for the municipal and domestic supply beneficial use. For the sediment matrix, a total of zero of 10 samples exceed the evaluation guideline for the cold freshwater habitat beneficial use and zero of 10 samples exceed the evaluation guideline for the warm freshwater habitat beneficial use. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109281, Arsenic
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 158230
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Arsenic.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan and identified as the maximum concentration for arsenic for irrigation supply as 0.1 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109281, Arsenic
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 157944
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Arsenic.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The California Maximum Contaminant Level for Arsenic is 10 ug/L.
Guideline Reference: California MCLs - Title 17 and Title 22 documents for 2019 - California Regulations Related to Drinking Water
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109281, Arsenic
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 157990
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Arsenic.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The California Maximum Contaminant Level for Arsenic is 10 ug/L.
Guideline Reference: California MCLs - Title 17 and Title 22 documents for 2019 - California Regulations Related to Drinking Water
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2013-06-10 and 2017-12-07
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109281, Arsenic
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 158232
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Arsenic.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan and identified as the maximum concentration for arsenic for irrigation supply as 0.1 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2013-06-10 and 2017-12-07
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109281, Arsenic
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 157778
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Arsenic.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The California Maximum Contaminant Level for Arsenic is 10 ug/L.
Guideline Reference: California MCLs - Title 17 and Title 22 documents for 2019 - California Regulations Related to Drinking Water
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109281, Arsenic
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 151378
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 7 samples exceeded the evaluation guideline for Arsenic .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for arsenic is 33 mg/Kg dry weight (MacDonald et al. 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2018-06-13
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109281, Arsenic
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 157713
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Arsenic.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan and identified as the maximum concentration for arsenic for irrigation supply as 0.1 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109281, Arsenic
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 151254
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 7 samples exceeded the evaluation guideline for Arsenic .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for arsenic is 33 mg/Kg dry weight (MacDonald et al. 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2018-06-13
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109281, Arsenic
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 15677
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Arsenic.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for arsenic is 33 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109281, Arsenic
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 15674
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Arsenic.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for arsenic is 33 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109281, Arsenic
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 15678
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Arsenic.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for arsenic is 33 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109281, Arsenic
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 15687
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Arsenic.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for arsenic is 33 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109281, Arsenic
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57818
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Arsenic.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for arsenic is 33 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109281, Arsenic
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57817
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Arsenic.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for arsenic is 33 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
 
DECISION ID
109298
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Azinphos-methyl (Guthion)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 109298, Azinphos-methyl (Guthion)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 158660
 
Pollutant: Azinphos-methyl (Guthion)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Azinphos Methyl. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The Criterion Continuous Concentration for freshwater aquatic life is 0.01 ug/L (National Recommended Water Quality Criteria, EPA 2016)
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Date for this waterbody was collected over the date range 2010-07-21 to 2013-06-19
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109298, Azinphos-methyl (Guthion)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 158763
 
Pollutant: Azinphos-methyl (Guthion)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Azinphos Methyl. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The Criterion Continuous Concentration for freshwater aquatic life is 0.01 ug/L (National Recommended Water Quality Criteria, EPA 2016)
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Date for this waterbody was collected over the date range 2010-07-21 to 2013-06-19
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109349
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Azoxystrobin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 109349, Azoxystrobin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 159136
 
Pollutant: Azoxystrobin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Azoxystrobin.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Azoxystrobin is the USEPA Aquatic Life Benchmark of 44 ug/L for an invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109349, Azoxystrobin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 159139
 
Pollutant: Azoxystrobin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Azoxystrobin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Azoxystrobin is the USEPA Aquatic Life Benchmark of 44 ug/L for an invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109349, Azoxystrobin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 159161
 
Pollutant: Azoxystrobin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Azoxystrobin.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Azoxystrobin is the USEPA Aquatic Life Benchmark of 44 ug/L for an invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109349, Azoxystrobin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 159110
 
Pollutant: Azoxystrobin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Azoxystrobin.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Azoxystrobin is the USEPA Aquatic Life Benchmark of 44 ug/L for an invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109349, Azoxystrobin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 159140
 
Pollutant: Azoxystrobin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Azoxystrobin.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Azoxystrobin is the USEPA Aquatic Life Benchmark of 44 ug/L for an invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109349, Azoxystrobin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 159113
 
Pollutant: Azoxystrobin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Azoxystrobin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Azoxystrobin is the USEPA Aquatic Life Benchmark of 44 ug/L for an invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109283
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Benzo(a)anthracene
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) list under section 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment. The pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the Section 303(d) list.

Six lines of evidence (LOEs) are available in the administrative record to assess this pollutant.
Sample and exceedance counts for the lines of evidence with the fraction identified as “none” or “not recorded” are grouped together with those having the fraction “total”, based on the analytical method used. The following is a summary of the sample and exceedances for each beneficial use:

Zero of four sediment samples exceed the aquatic life evaluation guideline. This sample size is insufficient to determine an applicable beneficial use support rating with the power and confidence of the Listing Policy. In accordance with Table 3.1 of the Listing Policy, a minimum of 16 samples is needed to determine if a beneficial use is fully supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:

1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero samples exceed the evaluation guideline and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109283, Benzo(a)anthracene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 151117
 
Pollutant: Benzo(a)anthracene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Benz(a)anthracene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Benz[a]anthrazene from MacDonald et al., 2000a which states that the probable effect concentration for Benz[a]anthrazene is 1050 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109283, Benzo(a)anthracene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 15546
 
Pollutant: Benzo(a)anthracene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Benzo(a)anthracene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for Benzo(a)anthracene is 1050 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109283, Benzo(a)anthracene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 15740
 
Pollutant: Benzo(a)anthracene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Benzo(a)anthracene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for Benzo(a)anthracene is 1050 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109283, Benzo(a)anthracene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 151402
 
Pollutant: Benzo(a)anthracene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Benz(a)anthracene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Benz[a]anthrazene from MacDonald et al., 2000a which states that the probable effect concentration for Benz[a]anthrazene is 1050 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109283, Benzo(a)anthracene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 15559
 
Pollutant: Benzo(a)anthracene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Benzo(a)anthracene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for Benzo(a)anthracene is 1050 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109283, Benzo(a)anthracene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 15741
 
Pollutant: Benzo(a)anthracene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Benzo(a)anthracene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for Benzo(a)anthracene is 1050 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
 
DECISION ID
109282
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Benzo(a)pyrene
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) list under section 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment. The pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the Section 303(d) list.

Six lines of evidence (LOEs) are available in the administrative record to assess this pollutant.
Sample and exceedance counts for the lines of evidence with the fraction identified as “none” or “not recorded” are grouped together with those having the fraction “total”, based on the analytical method used. The following is a summary of the sample and exceedances for each beneficial use:

Zero of four sediment samples exceed the aquatic life evaluation guideline. This sample size is insufficient to determine an applicable beneficial use support rating with the power and confidence of the Listing Policy. In accordance with Table 3.1 of the Listing Policy, a minimum of 16 samples is needed to determine if a beneficial use is fully supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:

1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero samples exceed the evaluation guideline and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109282, Benzo(a)pyrene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 15358
 
Pollutant: Benzo(a)pyrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Benzo(a)pyrene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for Benzo(a)Pyrene is 1450 ug/Kg dry weight (Macdonald et al. 2000)
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109282, Benzo(a)pyrene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 15407
 
Pollutant: Benzo(a)pyrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Benzo(a)pyrene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for Benzo(a)Pyrene is 1450 ug/Kg dry weight (Macdonald et al. 2000)
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109282, Benzo(a)pyrene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 15371
 
Pollutant: Benzo(a)pyrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Benzo(a)pyrene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for Benzo(a)Pyrene is 1450 ug/Kg dry weight (Macdonald et al. 2000)
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109282, Benzo(a)pyrene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 151196
 
Pollutant: Benzo(a)pyrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Benzo(a)pyrene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Benzo[a]pyrene from MacDonald et al., 2000a which states that the probable effect concentration for Benzo[a]pyrene is 1450 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109282, Benzo(a)pyrene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 151258
 
Pollutant: Benzo(a)pyrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Benzo(a)pyrene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Benzo[a]pyrene from MacDonald et al., 2000a which states that the probable effect concentration for Benzo[a]pyrene is 1450 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109282, Benzo(a)pyrene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 15408
 
Pollutant: Benzo(a)pyrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Benzo(a)pyrene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for Benzo(a)Pyrene is 1450 ug/Kg dry weight (Macdonald et al. 2000)
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
 
DECISION ID
109324
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Bifenthrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 at least one line of evidence is necessary to assess listing status, but under section 3.6 at least two lines of evidence are necessary to assess listing status and the pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the section 303(d) List.

12 lines of evidence are available in the administrative record to assess this pollutant. Zero of seven sediment samples exceed the evaluation guideline and zero of zero water samples exceed the evaluation guideline used to interpret the narrative water quality objective for aquatic life protection. This sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported using table 3.1. Therefore, the use support rating is set to 'insufficient information'.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the samples exceed the evaluation guidelines and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109324, Bifenthrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 148432
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends Project (SPoT) data for San Luis Obispo Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Bifenthrin.
Data Reference: SPoT sediment data: 6/5/2018--6/13/2018.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for bifenthrin is the median lethal concentration (LC50) of 0.43 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.43 ug/g is the geometric mean of LC50 values for bifenthrin from Amweg et al. (2005) and Amweg and Weston (2007).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB
Temporal Representation: Data for this waterbody were collected on 06/13/2018.
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAPP and the SWAMP-SPoT QAPP. QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109324, Bifenthrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 158871
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bifenthrin. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of bifenthrin does not exceed 0.0006 ug/L (Fojut et al., 2012).
Guideline Reference: Water quality criteria report for Bifenthrin. Phase III: application of the pesticide water quality criteria methodology.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV).
Temporal Representation: Date for this waterbody was collected over the date range 2015-05-20 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109324, Bifenthrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 159262
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bifenthrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of bifenthrin does not exceed 0.0006 ug/L (Fojut et al., 2012).
Guideline Reference: Water quality criteria report for Bifenthrin. Phase III: application of the pesticide water quality criteria methodology.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Date for this waterbody was collected over the date range 2015-09-09 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109324, Bifenthrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 151723
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Bifenthrin .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for bifenthrin is the median lethal concentration (LC50) of 0.43 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.43 ug/g is the geometric mean of LC50 values for bifenthrin from Amweg et al. (2005) and Amweg and Weston (2007).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2011-06-21 to 2017-06-05
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109324, Bifenthrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57827
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Bifenthrin.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for bifenthrin is the median lethal concentration (LC50) of 0.43 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.43 ug/g is the geometric mean of three toxicity LC50 values from Amweg et al. (2005) and one toxicity LC50 value from Amweg and Weston (2007).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109324, Bifenthrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 158967
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bifenthrin. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of bifenthrin does not exceed 0.0006 ug/L (Fojut et al., 2012).
Guideline Reference: Water quality criteria report for Bifenthrin. Phase III: application of the pesticide water quality criteria methodology.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV).
Temporal Representation: Date for this waterbody was collected over the date range 2015-05-20 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109324, Bifenthrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 159263
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bifenthrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of bifenthrin does not exceed 0.0006 ug/L (Fojut et al., 2012).
Guideline Reference: Water quality criteria report for Bifenthrin. Phase III: application of the pesticide water quality criteria methodology.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Date for this waterbody was collected over the date range 2015-09-09 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109324, Bifenthrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57828
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Bifenthrin.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for bifenthrin is the median lethal concentration (LC50) of 0.43 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.43 ug/g is the geometric mean of three toxicity LC50 values from Amweg et al. (2005) and one toxicity LC50 value from Amweg and Weston (2007).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109324, Bifenthrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 158965
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bifenthrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of bifenthrin does not exceed 0.0006 ug/L (Fojut et al., 2012).
Guideline Reference: Water quality criteria report for Bifenthrin. Phase III: application of the pesticide water quality criteria methodology.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM).
Temporal Representation: Date for this waterbody was collected over the date range 2015-09-09 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109324, Bifenthrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 158915
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bifenthrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of bifenthrin does not exceed 0.0006 ug/L (Fojut et al., 2012).
Guideline Reference: Water quality criteria report for Bifenthrin. Phase III: application of the pesticide water quality criteria methodology.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM).
Temporal Representation: Date for this waterbody was collected over the date range 2015-09-09 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109324, Bifenthrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 148433
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends Project (SPoT) data for San Luis Obispo Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Bifenthrin.
Data Reference: SPoT sediment data: 6/5/2018--6/13/2018.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for bifenthrin is the median lethal concentration (LC50) of 0.43 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.43 ug/g is the geometric mean of LC50 values for bifenthrin from Amweg et al. (2005) and Amweg and Weston (2007).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB
Temporal Representation: Data for this waterbody were collected on 06/13/2018.
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAPP and the SWAMP-SPoT QAPP. QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109324, Bifenthrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 151411
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Bifenthrin .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for bifenthrin is the median lethal concentration (LC50) of 0.43 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.43 ug/g is the geometric mean of LC50 values for bifenthrin from Amweg et al. (2005) and Amweg and Weston (2007).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2011-06-21 to 2017-06-05
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109284
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Cadmium
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Twenty lines of evidence are available in the administrative record to assess this pollutant. Zero of 14 water samples exceed the evaluation guidelines used to interpret the narrative water quality objective for aquatic life habitat, municipal or domestic water supply, and agricultural beneficial uses. Zero of 10 sediment samples exceed the evaluation guidelines used to interpret the narrative water quality objective for aquatic habitat beneficial uses. A minimum of 16 samples is needed to determine if a beneficial use is supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported using table 3.1. Therefore, the use support ratings are set to 'insufficient information'.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of 14 water samples exceed the evaluation guidelines used to interpret the narrative water quality objective for aquatic life habitat, municipal or domestic water supply, and agricultural beneficial uses. Zero of 10 sediment samples exceed the evaluation guidelines used to interpret the narrative water quality objective for aquatic habitat beneficial uses. These sample sizes are insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109284, Cadmium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 15492
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cadmium.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for cadmium is 4.98 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109284, Cadmium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 15472
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cadmium.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for cadmium is 4.98 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109284, Cadmium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 15493
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cadmium.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for cadmium is 4.98 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109284, Cadmium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57830
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cadmium.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for cadmium is 4.98 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109284, Cadmium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57829
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cadmium.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for cadmium is 4.98 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109284, Cadmium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 159231
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Cadmium.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The California Maximum Contaminant Level for cadmium is 0.005 mg/L (California Code of Regulations, Title 22).
Guideline Reference: California MCLs - Title 17 and Title 22 documents for 2019 - California Regulations Related to Drinking Water
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109284, Cadmium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 159971
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Cadmium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2013-06-10 and 2017-12-07
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109284, Cadmium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 159923
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Cadmium.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109284, Cadmium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 159641
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Cadmium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2013-06-10 and 2017-12-07
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109284, Cadmium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 151508
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 7 samples exceeded the evaluation guideline for Cadmium .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for cadmium in 4.98 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2018-06-13
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109284, Cadmium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 159644
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Cadmium.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109284, Cadmium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 159236
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Cadmium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The California Maximum Contaminant Level for cadmium is 0.005 mg/L (California Code of Regulations, Title 22).
Guideline Reference: California MCLs - Title 17 and Title 22 documents for 2019 - California Regulations Related to Drinking Water
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2013-06-10 and 2017-12-07
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109284, Cadmium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 159890
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Cadmium.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan and identified as the maximum concentration for cadmium for irrigation supply as 0.01 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109284, Cadmium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 159645
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Cadmium.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan and identified as the maximum concentration for cadmium for irrigation supply as 0.01 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109284, Cadmium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 151491
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 7 samples exceeded the evaluation guideline for Cadmium .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for cadmium in 4.98 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2018-06-13
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109284, Cadmium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 159647
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Cadmium.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109284, Cadmium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 159791
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Cadmium.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109284, Cadmium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 159911
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Cadmium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan and identified as the maximum concentration for cadmium for irrigation supply as 0.01 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2013-06-10 and 2017-12-07
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109284, Cadmium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 159237
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Cadmium.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The California Maximum Contaminant Level for cadmium is 0.005 mg/L (California Code of Regulations, Title 22).
Guideline Reference: California MCLs - Title 17 and Title 22 documents for 2019 - California Regulations Related to Drinking Water
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109284, Cadmium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 15471
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cadmium.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for cadmium is 4.98 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
 
DECISION ID
109331
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Carbophenothion
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 109331, Carbophenothion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 160474
 
Pollutant: Carbophenothion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Carbophenothion.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Drinking water notification levels are published by the Division of Drinking Water and are for chemicals for which there is no drinking water MCL. If a notification level is exceeded, local government notification is required and customer notification is recommended. The criteria for Carbophenothion (Trithion) is 0.007 mg/L.
Guideline Reference: CDPH Archived Advisory Levels for Drinking Water. Archived Advisory Levels are currently considered Notification Levels.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2013-06-19
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109285
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Chlordane
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) list under section 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment. The pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the Section 303(d) list.

Four lines of evidence (LOEs) are available in the administrative record to assess this pollutant.

Zero of seven sediment samples exceed the aquatic life evaluation guideline. This sample size is insufficient to determine an applicable beneficial use support rating with the power and confidence of the Listing Policy. In accordance with Table 3.1 of the Listing Policy, a minimum of 16 samples is needed to determine if a beneficial use is fully supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:

1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero samples exceed the evaluation guideline and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109285, Chlordane
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57840
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chlordane, Total.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for chlordane is 17.6 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109285, Chlordane
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 152067
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Chlordane .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Chlordane from MacDonald et al., 2000a which states that the probable effect concentration for Chlordane is 17.6 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2017-06-05
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109285, Chlordane
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 151861
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Chlordane .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Chlordane from MacDonald et al., 2000a which states that the probable effect concentration for Chlordane is 17.6 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2017-06-05
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109285, Chlordane
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57841
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chlordane, Total.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for chlordane is 17.6 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
 
DECISION ID
109338
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Chromium
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the Clean Water Act (CWA) section 303(d) List under section 3.1 and 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment. The pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the Section 303(d) List.

A total of 22 lines of evidence are available in the administrative record to assess this pollutant. Sample and exceedance counts for the lines of evidence with the fraction identified as “none” or “not recorded” are grouped together with those having the fraction “total”, based on the analytical method used. For the water matrix, a total of zero of 14 samples exceed the water quality objective for the agricultural supply beneficial use and zero of 14 samples exceed the water quality objective for the municipal and domestic supply beneficial use. For the sediment matrix, a total of 10 of 10 samples exceed the evaluation guideline for the cold freshwater habitat beneficial use and 10 of 10 samples exceed the evaluation guideline for the warm freshwater habitat beneficial use but these samples are not associated with sediment toxicity. These data are insufficient to determine the applicable beneficial use support rating with the power and confidence required by the Listing Policy.

After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. For the water matrix, a total of zero of 14 samples exceed the water quality objective for the agricultural supply beneficial use and zero of 14 samples exceed the water quality objective for the municipal and domestic supply beneficial use. For the sediment matrix, a total of 10 of 10 samples exceed the evaluation guideline for the cold freshwater habitat beneficial use and 10 of 10 samples exceed the evaluation guideline for the warm freshwater habitat beneficial use but these samples are not associated with sediment toxicity. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109338, Chromium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57812
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Chromium.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for chromium is 111 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109338, Chromium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 148691
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 1 of the 8 samples collected by SWAMP Stream Pollution Trends for San Luis Obispo Creek (below Osos Street) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Growth (wt/surv indiv), Chironomus dilutus, for Survival, Hyalella azteca, for Survival, Chironomus dilutus, for Ash Free Dry Mass, Chironomus dilutus, for Growth (wt/surv indiv)
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Central Coastal Basin Plan 2019).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( 310SLB )
Temporal Representation: The samples were collected between the dates of 2010-06-21 and 2018-06-13.
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109338, Chromium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 161902
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Chromium.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All inland surface waters, enclosed bays, and estuaries shall not contain concentrations of inorganic chemicals in excess of the maximum contaminant levels for primary drinking water standards specified in California Code of Regulations, Title 22, Division 4, Chapter 15, Sections 64431 and 64433.2.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The California Maximum Contaminant Level for total chromium is 0.05 mg/L (California Code of Regulations, Title 22).
Guideline Reference: California MCLs - Title 17 and Title 22 documents for 2019 - California Regulations Related to Drinking Water
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109338, Chromium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 161859
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Chromium.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All inland surface waters, enclosed bays, and estuaries shall not contain concentrations of inorganic chemicals in excess of the maximum contaminant levels for primary drinking water standards specified in California Code of Regulations, Title 22, Division 4, Chapter 15, Sections 64431 and 64433.2.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The California Maximum Contaminant Level for total chromium is 0.05 mg/L (California Code of Regulations, Title 22).
Guideline Reference: California MCLs - Title 17 and Title 22 documents for 2019 - California Regulations Related to Drinking Water
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109338, Chromium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 162084
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Chromium.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan and identified as the maximum concentration for chromium for irrigation supply is 0.10 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109338, Chromium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 162037
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Chromium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan and identified as the maximum concentration for chromium for irrigation supply is 0.10 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2013-06-10 and 2017-12-07
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109338, Chromium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57813
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Chromium.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for chromium is 111 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109338, Chromium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 148677
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 1 of the 8 samples collected by SWAMP Stream Pollution Trends for San Luis Obispo Creek (below Osos Street) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Growth (wt/surv indiv), Chironomus dilutus, for Survival, Hyalella azteca, for Survival, Chironomus dilutus, for Ash Free Dry Mass, Chironomus dilutus, for Growth (wt/surv indiv)
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Central Coastal Basin Plan 2019).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( 310SLB )
Temporal Representation: The samples were collected between the dates of 2010-06-21 and 2018-06-13.
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109338, Chromium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 15913
 
Pollutant: Chromium (total)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Chromium.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for chromium is 111 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109338, Chromium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 15934
 
Pollutant: Chromium (total)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Chromium.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for chromium is 111 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109338, Chromium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 15914
 
Pollutant: Chromium (total)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Chromium.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for chromium is 111 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109338, Chromium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 15935
 
Pollutant: Chromium (total)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Chromium.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for chromium is 111 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109338, Chromium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 23972
 
Pollutant: Invertebrate Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Toxicity, Hyalella azteca Survival (%) 10 days. Toxicity is defined by SWAMP (2004) as follows: Significant toxicity in the survival endpoint when compared to the negative control based on a statistical test with alpha of less than 5%, and less than the evaluation threshold (both criteria are met).
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Significant reduction of survival of test organism relative to the control (alpha < 0.05) and test organism survival is 20% less than the control survival.
Guideline Reference: Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109338, Chromium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 23973
 
Pollutant: Invertebrate Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Toxicity, Hyalella azteca Survival (%) 10 days. Toxicity is defined by SWAMP (2004) as follows: Significant toxicity in the survival endpoint when compared to the negative control based on a statistical test with alpha of less than 5%, and less than the evaluation threshold (both criteria are met).
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Significant reduction of survival of test organism relative to the control (alpha < 0.05) and test organism survival is 20% less than the control survival.
Guideline Reference: Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109338, Chromium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57917
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to evaluate sediment toxicity. None of the samples exhibited significant toxicity. The toxicity tests included survival and growth of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 3 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
Guideline Reference: SWAMP_Memo_Toxicity_Data_Intrepretation
 
Spatial Representation: The samples were collected at station 310SLBxxx.
Temporal Representation: The samples were collected in June 2008.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2002) was followed.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109338, Chromium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57914
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to evaluate sediment toxicity. None of the samples exhibited significant toxicity. The toxicity tests included survival and growth of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Coastal Confluences 2008 2009
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 3 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
Guideline Reference: SWAMP_Memo_Toxicity_Data_Intrepretation
 
Spatial Representation: The samples were collected at station 310SLB - San Luis Creek at San Luis Bay Drive.
Temporal Representation: The samples were collected in May 2009.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2002) was followed.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109338, Chromium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57915
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to evaluate sediment toxicity. None of the samples exhibited significant toxicity. The toxicity tests included survival and growth of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Santa Lucia Watershed Rotation 2009
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 3 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
Guideline Reference: SWAMP_Memo_Toxicity_Data_Intrepretation
 
Spatial Representation: The samples were collected at station 310SLBxxx.
Temporal Representation: The samples were collected in May 2009.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2002) was followed.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109338, Chromium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 80335
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to evaluate sediment toxicity. None of the samples exhibited significant toxicity. The toxicity tests included survival and growth of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Santa Lucia Watershed Rotation 2009
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 3 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
Guideline Reference: SWAMP_Memo_Toxicity_Data_Intrepretation
 
Spatial Representation: The samples were collected at station 310SLBxxx.
Temporal Representation: The samples were collected in May 2009.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2002) was followed.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109338, Chromium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 80334
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to evaluate sediment toxicity. None of the samples exhibited significant toxicity. The toxicity tests included survival and growth of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Coastal Confluences 2008 2009
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 3 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
Guideline Reference: SWAMP_Memo_Toxicity_Data_Intrepretation
 
Spatial Representation: The samples were collected at station 310SLB - San Luis Creek at San Luis Bay Drive.
Temporal Representation: The samples were collected in May 2009.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2002) was followed.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109338, Chromium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 80337
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to evaluate sediment toxicity. None of the samples exhibited significant toxicity. The toxicity tests included survival and growth of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 3 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
Guideline Reference: SWAMP_Memo_Toxicity_Data_Intrepretation
 
Spatial Representation: The samples were collected at station 310SLBxxx.
Temporal Representation: The samples were collected in June 2008.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2002) was followed.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109338, Chromium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 161706
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Chromium.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan and identified as the maximum concentration for chromium for irrigation supply is 0.10 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109338, Chromium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 151983
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 7
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 7 of the 7 samples exceeded the evaluation guideline for Chromium .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for chromium in 111 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2018-06-13
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109338, Chromium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 151981
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 7
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 7 of the 7 samples exceeded the evaluation guideline for Chromium .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for chromium in 111 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2018-06-13
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109338, Chromium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 162134
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Chromium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All inland surface waters, enclosed bays, and estuaries shall not contain concentrations of inorganic chemicals in excess of the maximum contaminant levels for primary drinking water standards specified in California Code of Regulations, Title 22, Division 4, Chapter 15, Sections 64431 and 64433.2.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The California Maximum Contaminant Level for total chromium is 0.05 mg/L (California Code of Regulations, Title 22).
Guideline Reference: California MCLs - Title 17 and Title 22 documents for 2019 - California Regulations Related to Drinking Water
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2013-06-10 and 2017-12-07
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109288
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Chrysene (C1-C4)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) list under section 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment. The pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the Section 303(d) list.

Six lines of evidence (LOEs) are available in the administrative record to assess this pollutant.
Sample and exceedance counts for the lines of evidence with the fraction identified as “none” or “not recorded” are grouped together with those having the fraction “total”, based on the analytical method used. The following is a summary of the sample and exceedances for each beneficial use:

Zero of four sediment samples exceed the aquatic life evaluation guideline. This sample size is insufficient to determine an applicable beneficial use support rating with the power and confidence of the Listing Policy. In accordance with Table 3.1 of the Listing Policy, a minimum of 16 samples is needed to determine if a beneficial use is fully supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:

1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero samples exceed the evaluation guideline and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109288, Chrysene (C1-C4)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 15998
 
Pollutant: Chrysene (C1-C4)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chrysene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for Chrysene is 1290 ug/Kg dry weight (Macdonald et al. 2000)
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109288, Chrysene (C1-C4)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 16017
 
Pollutant: Chrysene (C1-C4)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chrysene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for Chrysene is 1290 ug/Kg dry weight (Macdonald et al. 2000)
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109288, Chrysene (C1-C4)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 15999
 
Pollutant: Chrysene (C1-C4)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chrysene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for Chrysene is 1290 ug/Kg dry weight (Macdonald et al. 2000)
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109288, Chrysene (C1-C4)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 16018
 
Pollutant: Chrysene (C1-C4)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chrysene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for Chrysene is 1290 ug/Kg dry weight (Macdonald et al. 2000)
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109288, Chrysene (C1-C4)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 152248
 
Pollutant: Chrysene (C1-C4)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Chrysene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Chrysene from MacDonald et al., 2000a which states that the probable effect concentration for Chrysene is 1290 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109288, Chrysene (C1-C4)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 152228
 
Pollutant: Chrysene (C1-C4)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Chrysene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Chrysene from MacDonald et al., 2000a which states that the probable effect concentration for Chrysene is 1290 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109289
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Copper
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the Clean Water Act (CWA) section 303(d) List under section 3.1 and 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment. The pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the Section 303(d) List.

A total of 20 lines of evidence are available in the administrative record to assess this pollutant. Sample and exceedance counts for the lines of evidence with the fraction identified as “none” or “not recorded” are grouped together with those having the fraction “total”, based on the analytical method used. For the water matrix, a total of zero of 121 samples exceed the water quality objective for the agricultural supply beneficial use, three of 101 samples exceed the water quality objective for the cold freshwater habitat beneficial use, zero of 121 samples exceed the water quality objective for the municipal and domestic supply beneficial use and three of 101 samples exceed the water quality objective for the warm freshwater habitat beneficial use. For the sediment matrix, a total of zero of 10 samples exceed the evaluation guideline for the cold freshwater habitat beneficial use and zero of 10 samples exceed the evaluation guideline for the warm freshwater habitat beneficial use.

After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. For the water matrix, a total of zero of 121 samples exceed the water quality objective for the agricultural supply beneficial use, three of 101 samples exceed the water quality objective for the cold freshwater habitat beneficial use, zero of 121 samples exceed the water quality objective for the municipal and domestic supply beneficial use and three of 101 samples exceed the water quality objective for the warm freshwater habitat beneficial use. For the sediment matrix, a total of zero of 10 samples exceed the evaluation guideline for the cold freshwater habitat beneficial use and zero of 10 samples exceed the evaluation guideline for the warm freshwater habitat beneficial use. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109289, Copper
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 152110
 
Pollutant: Copper
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 7 samples exceeded the evaluation guideline for Copper .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for copper in 149 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2018-06-13
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109289, Copper
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 16081
 
Pollutant: Copper
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Copper.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for cooper is 149 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109289, Copper
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 162854
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 95
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 95 samples exceeded the water quality threshold for Copper.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Copper criteria for the protection of human health from the consumption of water and organisms is 1.300 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2011-01-06 and 2018-12-06
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109289, Copper
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 16847
 
Pollutant: Copper
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Copper.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for cooper is 149 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109289, Copper
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 16082
 
Pollutant: Copper
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Copper.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for cooper is 149 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109289, Copper
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 16848
 
Pollutant: Copper
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Copper.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for cooper is 149 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109289, Copper
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57815
 
Pollutant: Copper
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Copper.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for copper is 149 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109289, Copper
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57814
 
Pollutant: Copper
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Copper.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for copper is 149 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109289, Copper
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 162916
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 13
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 13 samples exceeded the water quality threshold for Copper.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan and identified as the maximum concentration for copper for irrigation supply as 0.2 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109289, Copper
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 152353
 
Pollutant: Copper
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 7 samples exceeded the evaluation guideline for Copper .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for copper in 149 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2018-06-13
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109289, Copper
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 163055
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 13
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 13 samples exceeded the water quality threshold for Copper.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Copper criteria for the protection of human health from the consumption of water and organisms is 1.300 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109289, Copper
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 162644
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 13
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 13 samples exceeded the water quality threshold for Copper.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109289, Copper
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 162690
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 13
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 13 samples exceeded the water quality threshold for Copper.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109289, Copper
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 162738
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 75
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 2 of the 75 samples exceeded the water quality threshold for Copper. Although a total of 95 samples were collected, 20 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Data for this waterbody was collected over the date range 2011-01-06 to 2018-12-06
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109289, Copper
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 162770
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 13
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 13 samples exceeded the water quality threshold for Copper.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan and identified as the maximum concentration for copper for irrigation supply as 0.2 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109289, Copper
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 162668
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 13
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 1 of 13 samples exceeded the water quality threshold for Copper.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109289, Copper
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 162923
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 95
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 95 samples exceeded the water quality threshold for Copper.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan and identified as the maximum concentration for copper for irrigation supply as 0.2 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2011-01-06 and 2018-12-06
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109289, Copper
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 162710
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 75
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 2 of the 75 samples exceeded the water quality threshold for Copper. Although a total of 95 samples were collected, 20 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Data for this waterbody was collected over the date range 2011-01-06 to 2018-12-06
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109289, Copper
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 162416
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 13
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 1 of 13 samples exceeded the water quality threshold for Copper.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109289, Copper
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 162852
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 13
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 13 samples exceeded the water quality threshold for Copper.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Copper criteria for the protection of human health from the consumption of water and organisms is 1.300 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109348
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Coumaphos
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 109348, Coumaphos
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 163105
 
Pollutant: Coumaphos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Coumaphos. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Coumaphos is the USEPA Aquatic Life Benchmark of 0.037 ug/L for invertabretes (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Date for this waterbody was collected over the date range 2010-07-21 to 2013-06-19
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109348, Coumaphos
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 162761
 
Pollutant: Coumaphos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Coumaphos. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Coumaphos is the USEPA Aquatic Life Benchmark of 0.037 ug/L for invertabretes (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Date for this waterbody was collected over the date range 2010-07-21 to 2013-06-19
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109335
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Cyfluthrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 at least one line of evidence is necessary to assess listing status, but under section 3.6 at least two lines of evidence are necessary to assess listing status and the pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the section 303(d) List.

12 lines of evidence are available in the administrative record to assess this pollutant. Zero of seven sediment samples exceed the evaluation guideline and zero of zero water samples exceed the evaluation guideline used to interpret the narrative water quality objective for aquatic life protection. This sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported using table 3.1. Therefore, the use support rating is set to 'insufficient information'.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the samples exceed the evaluation guidelines and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109335, Cyfluthrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 163427
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyfluthrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of cyfluthrin does not exceed 0.00005 ug/L (0.05 ng/L) more than once every three years on the average (Fojut et al., 2012).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM).
Temporal Representation: Date for this waterbody was collected over the date range 2015-09-09 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109335, Cyfluthrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 163155
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyfluthrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of cyfluthrin does not exceed 0.00005 ug/L (0.05 ng/L) more than once every three years on the average (Fojut et al., 2012).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Date for this waterbody was collected over the date range 2015-09-09 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109335, Cyfluthrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 163156
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyfluthrin. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of cyfluthrin does not exceed 0.00005 ug/L (0.05 ng/L) more than once every three years on the average (Fojut et al., 2012).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV).
Temporal Representation: Date for this waterbody was collected over the date range 2015-05-20 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109335, Cyfluthrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 163407
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyfluthrin. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of cyfluthrin does not exceed 0.00005 ug/L (0.05 ng/L) more than once every three years on the average (Fojut et al., 2012).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV).
Temporal Representation: Date for this waterbody was collected over the date range 2015-05-20 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109335, Cyfluthrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 152142
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Cyfluthrin, total .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for cyfluthrin is the median lethal concentration (LC50) of 1.1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.1 ug/g is the geometric mean of LC50 values for cyfluthrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2011-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109335, Cyfluthrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 152139
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Cyfluthrin, total .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for cyfluthrin is the median lethal concentration (LC50) of 1.1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.1 ug/g is the geometric mean of LC50 values for cyfluthrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2011-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109335, Cyfluthrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 163213
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyfluthrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of cyfluthrin does not exceed 0.00005 ug/L (0.05 ng/L) more than once every three years on the average (Fojut et al., 2012).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM).
Temporal Representation: Date for this waterbody was collected over the date range 2015-09-09 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109335, Cyfluthrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 148434
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends Project (SPoT) data for San Luis Obispo Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Cyfluthrin, total.
Data Reference: SPoT sediment data: 6/5/2018--6/13/2018.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for cyfluthrin is the median lethal concentration (LC50) of 1.1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.1 ug/g is the geometric mean of LC50 values for cyfluthrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB
Temporal Representation: Data for this waterbody were collected on 06/13/2018.
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAPP and the SWAMP-SPoT QAPP. QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109335, Cyfluthrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 148435
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends Project (SPoT) data for San Luis Obispo Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Cyfluthrin, total.
Data Reference: SPoT sediment data: 6/5/2018--6/13/2018.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for cyfluthrin is the median lethal concentration (LC50) of 1.1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.1 ug/g is the geometric mean of LC50 values for cyfluthrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB
Temporal Representation: Data for this waterbody were collected on 06/13/2018.
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAPP and the SWAMP-SPoT QAPP. QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109335, Cyfluthrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 163409
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyfluthrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of cyfluthrin does not exceed 0.00005 ug/L (0.05 ng/L) more than once every three years on the average (Fojut et al., 2012).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Date for this waterbody was collected over the date range 2015-09-09 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109335, Cyfluthrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57820
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cyfluthrin, total.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for cyfluthrin is the median lethal concentration (LC50) of 1.1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.1 ug/g is the geometric mean of LC50 values for cyfluthrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109335, Cyfluthrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57821
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cyfluthrin, total.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for cyfluthrin is the median lethal concentration (LC50) of 1.1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.1 ug/g is the geometric mean of LC50 values for cyfluthrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
 
DECISION ID
109337
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Cyhalothrin, Lambda
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 at least one line of evidence is necessary to assess listing status, but under section 3.6 at least two lines of evidence are necessary to assess listing status and the pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the section 303(d) List.

12 lines of evidence are available in the administrative record to assess this pollutant. Zero of seven sediment samples exceed the evaluation guideline and zero of zero water samples exceed the evaluation guideline used to interpret the narrative water quality objective for aquatic life protection. This sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported using table 3.1. Therefore, the use support rating is set to 'insufficient information'.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the samples exceed the evaluation guidelines and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109337, Cyhalothrin, Lambda
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 167335
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Lambda-cyhalothrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of lambda-cyhalothrin does not exceed 0.0005 ug/L (0.5 ng/L) more than once every three years on the average (Fojut et al., 2012).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM).
Temporal Representation: Date for this waterbody was collected over the date range 2015-09-09 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109337, Cyhalothrin, Lambda
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 167353
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Lambda-cyhalothrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of lambda-cyhalothrin does not exceed 0.0005 ug/L (0.5 ng/L) more than once every three years on the average (Fojut et al., 2012).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Date for this waterbody was collected over the date range 2015-09-09 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109337, Cyhalothrin, Lambda
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 148437
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends Project (SPoT) data for San Luis Obispo Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Cyhalothrin, Total lambda-.
Data Reference: SPoT sediment data: 6/5/2018--6/13/2018.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for lambda-cyhalothrin is the median lethal concentration (LC50) of 0.44 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.44 ug/g is the geometric mean of LC50 values for lambda-cyhalothrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB
Temporal Representation: Data for this waterbody were collected on 06/13/2018.
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAPP and the SWAMP-SPoT QAPP. QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109337, Cyhalothrin, Lambda
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 148436
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends Project (SPoT) data for San Luis Obispo Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Cyhalothrin, Total lambda-.
Data Reference: SPoT sediment data: 6/5/2018--6/13/2018.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for lambda-cyhalothrin is the median lethal concentration (LC50) of 0.44 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.44 ug/g is the geometric mean of LC50 values for lambda-cyhalothrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB
Temporal Representation: Data for this waterbody were collected on 06/13/2018.
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAPP and the SWAMP-SPoT QAPP. QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109337, Cyhalothrin, Lambda
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 152490
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Cyhalothrin, Total lambda- .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for lambda-cyhalothrin is the median lethal concentration (LC50) of 0.44 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.44 ug/g is the geometric mean of LC50 values for lambda-cyhalothrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2011-06-21 to 2017-06-05
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109337, Cyhalothrin, Lambda
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 152675
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Cyhalothrin, Total lambda- .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for lambda-cyhalothrin is the median lethal concentration (LC50) of 0.44 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.44 ug/g is the geometric mean of LC50 values for lambda-cyhalothrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2011-06-21 to 2017-06-05
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109337, Cyhalothrin, Lambda
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 167552
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Lambda-cyhalothrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of lambda-cyhalothrin does not exceed 0.0005 ug/L (0.5 ng/L) more than once every three years on the average (Fojut et al., 2012).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Date for this waterbody was collected over the date range 2015-09-09 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109337, Cyhalothrin, Lambda
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57823
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cyhalothrin, lambda, total.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for lambda-cyhalothrin is the median lethal concentration (LC50) of 0.44 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.44 ug/g is the geometric mean of LC50 values for lambda-cyhalothrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109337, Cyhalothrin, Lambda
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 167352
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Lambda-cyhalothrin. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of lambda-cyhalothrin does not exceed 0.0005 ug/L (0.5 ng/L) more than once every three years on the average (Fojut et al., 2012).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV).
Temporal Representation: Date for this waterbody was collected over the date range 2015-05-20 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109337, Cyhalothrin, Lambda
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 167395
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Lambda-cyhalothrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of lambda-cyhalothrin does not exceed 0.0005 ug/L (0.5 ng/L) more than once every three years on the average (Fojut et al., 2012).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM).
Temporal Representation: Date for this waterbody was collected over the date range 2015-09-09 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109337, Cyhalothrin, Lambda
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 167530
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Lambda-cyhalothrin. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of lambda-cyhalothrin does not exceed 0.0005 ug/L (0.5 ng/L) more than once every three years on the average (Fojut et al., 2012).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV).
Temporal Representation: Date for this waterbody was collected over the date range 2015-05-20 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109337, Cyhalothrin, Lambda
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57822
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cyhalothrin, lambda, total.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for lambda-cyhalothrin is the median lethal concentration (LC50) of 0.44 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.44 ug/g is the geometric mean of LC50 values for lambda-cyhalothrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
 
DECISION ID
109325
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Cypermethrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 at least one line of evidence is necessary to assess listing status, but under section 3.6 at least two lines of evidence are necessary to assess listing status and the pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the section 303(d) List.

12 lines of evidence are available in the administrative record to assess this pollutant. Zero of seven sediment samples exceed the evaluation guideline and zero of zero water samples exceed the evaluation guideline used to interpret the narrative water quality objective for aquatic life protection. This sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported using table 3.1. Therefore, the use support rating is set to 'insufficient information'.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the samples exceed the evaluation guidelines and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109325, Cypermethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57832
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cypermethrin, total.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for cypermethrin is the median lethal concentration (LC50) of 0.3 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.3 ug/g is the geometric mean of LC50 values for cypermethrin from Maund et al. (2002).
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109325, Cypermethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57831
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cypermethrin, total.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for cypermethrin is the median lethal concentration (LC50) of 0.3 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.3 ug/g is the geometric mean of LC50 values for cypermethrin from Maund et al. (2002).
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109325, Cypermethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 163753
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cypermethrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of cypermethrin does not exceed 0.0002 ug/L (0.2 ng/L) more than once every three years on the average (Fojut et al. ,2012).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM).
Temporal Representation: Date for this waterbody was collected over the date range 2015-09-09 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109325, Cypermethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 163539
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cypermethrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of cypermethrin does not exceed 0.0002 ug/L (0.2 ng/L) more than once every three years on the average (Fojut et al. ,2012).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM).
Temporal Representation: Date for this waterbody was collected over the date range 2015-09-09 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109325, Cypermethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 163625
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cypermethrin. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of cypermethrin does not exceed 0.0002 ug/L (0.2 ng/L) more than once every three years on the average (Fojut et al. ,2012).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV).
Temporal Representation: Date for this waterbody was collected over the date range 2015-05-20 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109325, Cypermethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 163181
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cypermethrin. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of cypermethrin does not exceed 0.0002 ug/L (0.2 ng/L) more than once every three years on the average (Fojut et al. ,2012).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV).
Temporal Representation: Date for this waterbody was collected over the date range 2015-05-20 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109325, Cypermethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 152839
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Cypermethrin, Total .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for cypermethrin is the median lethal concentration (LC50) of 0.3 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.3 ug/g is the geometric mean of LC50 values for cypermethrin from Maund et al. (2002).
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109325, Cypermethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 163218
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cypermethrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of cypermethrin does not exceed 0.0002 ug/L (0.2 ng/L) more than once every three years on the average (Fojut et al. ,2012).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Date for this waterbody was collected over the date range 2015-09-09 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109325, Cypermethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 148439
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends Project (SPoT) data for San Luis Obispo Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Cypermethrin, Total.
Data Reference: SPoT sediment data: 6/5/2018--6/13/2018.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for cypermethrin is the median lethal concentration (LC50) of 0.3 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.3 ug/g is the geometric mean of LC50 values for cypermethrin from Maund et al. (2002).
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB
Temporal Representation: Data for this waterbody were collected on 06/13/2018.
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAPP and the SWAMP-SPoT QAPP. QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109325, Cypermethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 152741
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Cypermethrin, Total .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for cypermethrin is the median lethal concentration (LC50) of 0.3 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.3 ug/g is the geometric mean of LC50 values for cypermethrin from Maund et al. (2002).
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109325, Cypermethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 148438
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends Project (SPoT) data for San Luis Obispo Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Cypermethrin, Total.
Data Reference: SPoT sediment data: 6/5/2018--6/13/2018.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for cypermethrin is the median lethal concentration (LC50) of 0.3 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.3 ug/g is the geometric mean of LC50 values for cypermethrin from Maund et al. (2002).
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB
Temporal Representation: Data for this waterbody were collected on 06/13/2018.
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAPP and the SWAMP-SPoT QAPP. QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109325, Cypermethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 163650
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cypermethrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of cypermethrin does not exceed 0.0002 ug/L (0.2 ng/L) more than once every three years on the average (Fojut et al. ,2012).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Date for this waterbody was collected over the date range 2015-09-09 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
130072
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) List under section 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment. The pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the 303(d) List.

Four lines of evidence are available in the administrative record to assess this pollutant.

Four LOEs summarize sediment samples. Zero of six sediment samples exceed the DDD evaluation guideline (MacDonald et al., 2000a) set to protect for aquatic life beneficial uses.

After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. No sediment samples exceeded the evaluation guidelines set to protect aquatic life beneficial uses and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 130072, DDD (Dichlorodiphenyldichloroethane)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 152960
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for DDD (Dichlorodiphenyldichloroethane) .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Sum DDD from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDD is 28 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 130072, DDD (Dichlorodiphenyldichloroethane)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 152727
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for DDD (Dichlorodiphenyldichloroethane) .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Sum DDD from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDD is 28 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 130072, DDD (Dichlorodiphenyldichloroethane)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57833
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for DDD.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for sum of DDD is 28.0 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 130072, DDD (Dichlorodiphenyldichloroethane)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57834
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for DDD.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for sum of DDD is 28.0 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
 
DECISION ID
130142
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) List under section 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment. The pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the 303(d) List.

Four lines of evidence are available in the administrative record to assess this pollutant.

Four LOEs summarize sediment samples. Zero of seven sediment samples exceed the DDE evaluation guideline (MacDonald et al., 2000a) set to protect for aquatic life beneficial uses.

After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. No sediment samples exceeded the evaluation guidelines set to protect aquatic life beneficial uses and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 130142, DDE (Dichlorodiphenyldichloroethylene)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 153299
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for DDE (Dichlorodiphenyldichloroethylene) .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Sum DDE from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDE is 31.3 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2017-06-05
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 130142, DDE (Dichlorodiphenyldichloroethylene)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57844
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for DDE.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for sum of DDE is 31.3 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 130142, DDE (Dichlorodiphenyldichloroethylene)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57845
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for DDE.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for sum of DDE is 31.3 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 130142, DDE (Dichlorodiphenyldichloroethylene)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 153242
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for DDE (Dichlorodiphenyldichloroethylene) .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Sum DDE from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDE is 31.3 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2017-06-05
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
129838
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) List under section 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment. The pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the 303(d) List.

Eight lines of evidence are available in the administrative record to assess this pollutant. Note that this decision combines the pollutant ‘DDT’ and ‘total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD).’

Eight LOEs summarize sediment samples. Zero of seven sediment samples exceed the DDT evaluation guideline (MacDonald et al., 2000a) set to protect for aquatic life beneficial uses. Zero of seven sediment samples exceed the total DDT evaluation guideline (MacDonald et al., 2000a) set to protect for aquatic life beneficial uses.

After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. No sediment samples exceeded the evaluation guidelines set to protect aquatic life beneficial uses and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 129838, DDT (Dichlorodiphenyltrichloroethane)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57846
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for DDT.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for sum of DDT is 62.9 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 129838, DDT (Dichlorodiphenyltrichloroethane)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57912
 
Pollutant: Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for DDT, Total.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for total DDTs is 572 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 129838, DDT (Dichlorodiphenyltrichloroethane)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57847
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for DDT.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for sum of DDT is 62.9 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 129838, DDT (Dichlorodiphenyltrichloroethane)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 156005
 
Pollutant: Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD) .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Total DDTs from MacDonald et al., 2000a which states that the probable effect concentration for Total DDTs is 572 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2017-06-05
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 129838, DDT (Dichlorodiphenyltrichloroethane)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 156006
 
Pollutant: Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD) .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Total DDTs from MacDonald et al., 2000a which states that the probable effect concentration for Total DDTs is 572 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2017-06-05
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 129838, DDT (Dichlorodiphenyltrichloroethane)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 153293
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for DDT (Dichlorodiphenyltrichloroethane) .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Sum DDT from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDT is 62.9 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2017-06-05
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 129838, DDT (Dichlorodiphenyltrichloroethane)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57911
 
Pollutant: Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for DDT, Total.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for total DDTs is 572 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 129838, DDT (Dichlorodiphenyltrichloroethane)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 153273
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for DDT (Dichlorodiphenyltrichloroethane) .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Sum DDT from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDT is 62.9 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2017-06-05
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109336
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Deltamethrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 at least one line of evidence is necessary to assess listing status, but under section 3.6 at least two lines of evidence are necessary to assess listing status and the pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the section 303(d) List.

Ten lines of evidence are available in the administrative record to assess this pollutant. Zero of five sediment samples exceed the evaluation guideline and zero of zero water samples exceed the evaluation guideline used to interpret the narrative water quality objective for aquatic life protection. This sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported using table 3.1. Therefore, the use support rating is set to 'insufficient information'.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the samples exceed the evaluation guidelines and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109336, Deltamethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 163744
 
Pollutant: Deltamethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Deltamethrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Deltamethrin is the USEPA Aquatic Life Benchmark of 0.0041 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM).
Temporal Representation: Date for this waterbody was collected over the date range 2015-09-09 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109336, Deltamethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 153550
 
Pollutant: Deltamethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Deltamethrin .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for deltamethrin is the median lethal concentration (LC50) of 0.79 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.79 ug/g is the geometric mean of LC50 values for deltamethrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2013-05-30 to 2017-06-05
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109336, Deltamethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 163743
 
Pollutant: Deltamethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Deltamethrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Deltamethrin is the USEPA Aquatic Life Benchmark of 0.0041 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Date for this waterbody was collected over the date range 2015-09-09 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109336, Deltamethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57853
 
Pollutant: Deltamethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Deltamethrin.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for deltamethrin is the median lethal concentration (LC50) of 0.79 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.79 ug/g is the geometric mean of LC50 values for deltamethrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109336, Deltamethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57854
 
Pollutant: Deltamethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Deltamethrin.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for deltamethrin is the median lethal concentration (LC50) of 0.79 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.79 ug/g is the geometric mean of LC50 values for deltamethrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109336, Deltamethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 163466
 
Pollutant: Deltamethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Deltamethrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Deltamethrin is the USEPA Aquatic Life Benchmark of 0.0041 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM).
Temporal Representation: Date for this waterbody was collected over the date range 2015-09-09 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109336, Deltamethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 163786
 
Pollutant: Deltamethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Deltamethrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Deltamethrin is the USEPA Aquatic Life Benchmark of 0.0041 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Date for this waterbody was collected over the date range 2015-09-09 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109336, Deltamethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 153590
 
Pollutant: Deltamethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Deltamethrin .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for deltamethrin is the median lethal concentration (LC50) of 0.79 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.79 ug/g is the geometric mean of LC50 values for deltamethrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2013-05-30 to 2017-06-05
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109336, Deltamethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 163805
 
Pollutant: Deltamethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Deltamethrin. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Deltamethrin is the USEPA Aquatic Life Benchmark of 0.0041 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV).
Temporal Representation: Date for this waterbody was collected over the date range 2015-05-20 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109336, Deltamethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 163765
 
Pollutant: Deltamethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Deltamethrin. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Deltamethrin is the USEPA Aquatic Life Benchmark of 0.0041 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV).
Temporal Representation: Date for this waterbody was collected over the date range 2015-05-20 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109290
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Diazinon
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment. The pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the Section 303(d) List.

Sixteen lines of evidence are available in the administrative record to assess this pollutant. Note, four LOEs (47736, 47664, 47680 and 47690) summarize data from sediment pore water and the evaluation guideline is not relevant for this matrix. Therefore those LOEs were removed from and are not included in this decision. Zero of 12 water samples exceed the aquatic life evaluation guideline (Finlayson, 2004). Zero of five sediment samples exceed the aquatic life evaluation guideline. This sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is supported using table 3.1.

After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List because applicable water quality standards are not being exceeded.

This conclusion is based on the staff findings that:

1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.

2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.

3. Zero samples exceeded the water quality objectives. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.

4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109290, Diazinon
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 164178
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP SpecialStudies data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Diazinon.
Data Reference: Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).
Guideline Reference: Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2018-01-17 and 2018-01-17
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109290, Diazinon
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57855
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Diazinon.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for diazinon is the median lethal concentration (LC50) of 11 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 11 ug/g is the geometric mean of LC50 values for diazinon from Ding et al. (2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109290, Diazinon
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 153496
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Diazinon .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for diazinon is the median lethal concentration (LC50) of 11 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 11 ug/g is the geometric mean of LC50 values for diazinon from Ding et al. (2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2013-05-30
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109290, Diazinon
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 164179
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Diazinon.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).
Guideline Reference: Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109290, Diazinon
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 163852
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Diazinon.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).
Guideline Reference: Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109290, Diazinon
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 163980
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP SpecialStudies data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Diazinon.
Data Reference: Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).
Guideline Reference: Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2018-01-17 and 2018-01-17
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109290, Diazinon
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 163851
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Diazinon.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).
Guideline Reference: Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109290, Diazinon
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 164003
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Diazinon.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).
Guideline Reference: Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109290, Diazinon
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 163904
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Diazinon.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).
Guideline Reference: Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109290, Diazinon
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 163930
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Diazinon.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).
Guideline Reference: Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109290, Diazinon
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57856
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Diazinon.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for diazinon is the median lethal concentration (LC50) of 11 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 11 ug/g is the geometric mean of LC50 values for diazinon from Ding et al. (2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109290, Diazinon
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 16688
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Diazinon.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
Objective/Criterion Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Evaluation Guideline: One hour average maximum concentration 0.16 ug/L as stated in Sipmann and Finlayson (2000).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109290, Diazinon
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 16617
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Diazinon.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
Objective/Criterion Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Evaluation Guideline: One hour average maximum concentration 0.16 ug/L as stated in Sipmann and Finlayson (2000).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/19/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109290, Diazinon
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 16866
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Diazinon.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
Objective/Criterion Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Evaluation Guideline: One hour average maximum concentration 0.16 ug/L as stated in Sipmann and Finlayson (2000).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/19/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109290, Diazinon
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 16687
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Diazinon.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
Objective/Criterion Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Evaluation Guideline: One hour average maximum concentration 0.16 ug/L as stated in Sipmann and Finlayson (2000).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109290, Diazinon
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 153452
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Diazinon .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for diazinon is the median lethal concentration (LC50) of 11 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 11 ug/g is the geometric mean of LC50 values for diazinon from Ding et al. (2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2013-05-30
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109291
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Dichlorvos
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) List under sections 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Six lines of evidence are available in the administrative record to assess this pollutant. Zero of one water sample exceeded the aquatic life evaluation guideline and zero of two water samples exceed the drinking water health advisory level for municipal and domestic water supply. These sample sizes are insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is supported using table 3.1

After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List because applicable water quality standards are not being exceeded.

This conclusion is based on the staff findings that:

1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.

2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.

3. Zero samples exceed the evaluation guidelines. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.

4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 109291, Dichlorvos
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 164342
 
Pollutant: Dichlorvos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP SpecialStudies data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Dichlorvos.
Data Reference: Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The USEPA IRIS one-in-a-million cancer risk estimate from oral exposure for dichlorvos is 0.1 ug/L.
Guideline Reference: IRIS Database Calculations (summary)
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2018-01-17 and 2018-01-17
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109291, Dichlorvos
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 164361
 
Pollutant: Dichlorvos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Dichlorvos.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The USEPA IRIS one-in-a-million cancer risk estimate from oral exposure for dichlorvos is 0.1 ug/L.
Guideline Reference: IRIS Database Calculations (summary)
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2010-07-21
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109291, Dichlorvos
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 164376
 
Pollutant: Dichlorvos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dichlorvos. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Dichlorvos is the USEPA Aquatic Life Benchmark of 0.0058 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Date for this waterbody was collected over the date range 2010-07-21 to 2010-07-21
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109291, Dichlorvos
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 164438
 
Pollutant: Dichlorvos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dichlorvos. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Dichlorvos is the USEPA Aquatic Life Benchmark of 0.0058 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Date for this waterbody was collected over the date range 2010-07-21 to 2010-07-21
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109291, Dichlorvos
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 164255
 
Pollutant: Dichlorvos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP SpecialStudies data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Dichlorvos.
Data Reference: Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Dichlorvos is the USEPA Aquatic Life Benchmark of 0.0058 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2018-01-17 and 2018-01-17
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109291, Dichlorvos
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 164216
 
Pollutant: Dichlorvos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP SpecialStudies data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Dichlorvos.
Data Reference: Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Dichlorvos is the USEPA Aquatic Life Benchmark of 0.0058 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2018-01-17 and 2018-01-17
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109330
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Dicrotophos
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 109330, Dicrotophos
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 164385
 
Pollutant: Dicrotophos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Dicrotophos.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Dicrophos is the USEPA Aquatic Life Benchmark of 1.7 ug/L for invertebrates (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2010-07-21
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109330, Dicrotophos
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 164205
 
Pollutant: Dicrotophos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Dicrotophos.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The USEPA expected safe lifetime exposure limit in drinking water for Dicrotophos calculated using the IRIS Reference Dose, is 0.7 ug/L. This was calculated assuming 70 kg body weight, 2 liters/day water consumption, 20% relative source contribution from drinking water, and 0.0001 mg/kg/day as the reference dose.
Guideline Reference: IRIS Reference Summary (Various Pollutants)
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2010-07-21
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109330, Dicrotophos
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 164344
 
Pollutant: Dicrotophos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Dicrotophos.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Dicrophos is the USEPA Aquatic Life Benchmark of 1.7 ug/L for invertebrates (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2010-07-21
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109292
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Dieldrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) List under section 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment. The pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the Section 303(d) List.

Eight lines of evidence are available in the administrative record to assess this pollutant. Sample and exceedance counts for the lines of evidence with the fraction identified as “none” or “not recorded” are grouped together with those having the fraction “total”, based on the analytical method used.

Zero out of eight sediment samples exceeded the evaluation guideline for the aquatic life beneficial uses. This sample size is insufficient to determine an applicable beneficial use support rating with the power and confidence of the Listing Policy. In accordance with Table 3.1 of the Listing Policy, a minimum of 16 samples is needed to determine if a beneficial use is fully supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:

1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.

2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.

3. Zero out of eight sediment samples exceeded the evaluation guidelines. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.

4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109292, Dieldrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 16758
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Dieldrin.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for dieldrin is 61.8 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109292, Dieldrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57864
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Dieldrin.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for dieldrin is 61.8 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109292, Dieldrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57863
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Dieldrin.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for dieldrin is 61.8 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109292, Dieldrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 153730
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Dieldrin .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Dieldrin from MacDonald et al., 2000a which states that the probable effect concentration for Dieldrin is 61.8 ug/kg dw. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2017-06-05
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109292, Dieldrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 153441
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Dieldrin .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Dieldrin from MacDonald et al., 2000a which states that the probable effect concentration for Dieldrin is 61.8 ug/kg dw. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2017-06-05
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109292, Dieldrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 16543
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Dieldrin.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for dieldrin is 61.8 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109292, Dieldrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 16757
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Dieldrin.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for dieldrin is 61.8 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109292, Dieldrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 16544
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Dieldrin.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for dieldrin is 61.8 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
 
DECISION ID
109327
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Dimethoate
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) List under sections 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Four lines of evidence are available in the administrative record to assess this pollutant. Zero of three water samples exceeded the USEPA aquatic life evaluation guideline. This sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is supported using table 3.1.

After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List because applicable water quality standards are not being exceeded.

This conclusion is based on the staff findings that:

1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.

2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.

3. Zero samples exceed the evaluation guidelines. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.

4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 109327, Dimethoate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 164541
 
Pollutant: Dimethoate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Dimethoate.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Dimethoate is the USEPA Aquatic Life Benchmark of 0.5 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2013-06-19
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109327, Dimethoate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 164827
 
Pollutant: Dimethoate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Dimethoate.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Dimethoate is the USEPA Aquatic Life Benchmark of 0.5 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2013-06-19
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109327, Dimethoate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 164754
 
Pollutant: Dimethoate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP SpecialStudies data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Dimethoate.
Data Reference: Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Dimethoate is the USEPA Aquatic Life Benchmark of 0.5 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2018-01-17 and 2018-01-17
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109327, Dimethoate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 164648
 
Pollutant: Dimethoate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP SpecialStudies data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Dimethoate.
Data Reference: Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Dimethoate is the USEPA Aquatic Life Benchmark of 0.5 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2018-01-17 and 2018-01-17
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109293
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Disulfoton
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 109293, Disulfoton
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 165257
 
Pollutant: Disulfoton
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP SpecialStudies data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Disulfoton.
Data Reference: Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Disulfoton is the USEPA Aquatic Life Benchmark of 0.01 ug/L for an invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2018-01-17 and 2018-01-17
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109293, Disulfoton
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 165017
 
Pollutant: Disulfoton
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 1 of the 1 samples exceeded the water quality threshold for Disulfoton. Although a total of 2 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Disulfoton is the USEPA Aquatic Life Benchmark of 0.01 ug/L for an invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Data for this waterbody was collected over the date range 2010-07-21 to 2013-06-19
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109293, Disulfoton
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 165023
 
Pollutant: Disulfoton
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Disulfoton.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The USEPA drinking water health advisory for disulfoton is 0.7 ug/L.
Guideline Reference: 2018 Edition of the Drinking Water Standards and Health Advisories
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2013-06-19
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109293, Disulfoton
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 165147
 
Pollutant: Disulfoton
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP SpecialStudies data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Disulfoton.
Data Reference: Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Disulfoton is the USEPA Aquatic Life Benchmark of 0.01 ug/L for an invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2018-01-17 and 2018-01-17
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109293, Disulfoton
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 165019
 
Pollutant: Disulfoton
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP SpecialStudies data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Disulfoton.
Data Reference: Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The USEPA drinking water health advisory for disulfoton is 0.7 ug/L.
Guideline Reference: 2018 Edition of the Drinking Water Standards and Health Advisories
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2018-01-17 and 2018-01-17
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109293, Disulfoton
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 165194
 
Pollutant: Disulfoton
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 1 of the 1 samples exceeded the water quality threshold for Disulfoton. Although a total of 2 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Disulfoton is the USEPA Aquatic Life Benchmark of 0.01 ug/L for an invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Data for this waterbody was collected over the date range 2010-07-21 to 2013-06-19
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109294
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Dyfonate (Fonofos or Fonophos)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 109294, Dyfonate (Fonofos or Fonophos)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166984
 
Pollutant: Dyfonate (Fonofos or Fonophos)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Fonofos.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Fonofos is the maximum acceptable toxicant concentration (MATC) of 0.45 ug/L. The MATC is calculated as the geometric mean of the lowest observed effect concentration (LOEC) of 0.64 ug/L and the no observed effect concentration (NOEC) of 0.31 ug/L, as determined in a 21 day toxicity study with the water flea, Daphnia magna. Threshold values (LOEC and NOEC) are from USEPA Office of Pesticide Programs Ecotoxicity database.
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109294, Dyfonate (Fonofos or Fonophos)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166895
 
Pollutant: Dyfonate (Fonofos or Fonophos)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Fonofos.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Fonofos is the maximum acceptable toxicant concentration (MATC) of 0.45 ug/L. The MATC is calculated as the geometric mean of the lowest observed effect concentration (LOEC) of 0.64 ug/L and the no observed effect concentration (NOEC) of 0.31 ug/L, as determined in a 21 day toxicity study with the water flea, Daphnia magna. Threshold values (LOEC and NOEC) are from USEPA Office of Pesticide Programs Ecotoxicity database.
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109294, Dyfonate (Fonofos or Fonophos)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166740
 
Pollutant: Dyfonate (Fonofos or Fonophos)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Fonofos.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Fonofos is the maximum acceptable toxicant concentration (MATC) of 0.45 ug/L. The MATC is calculated as the geometric mean of the lowest observed effect concentration (LOEC) of 0.64 ug/L and the no observed effect concentration (NOEC) of 0.31 ug/L, as determined in a 21 day toxicity study with the water flea, Daphnia magna. Threshold values (LOEC and NOEC) are from USEPA Office of Pesticide Programs Ecotoxicity database.
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109294, Dyfonate (Fonofos or Fonophos)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166918
 
Pollutant: Dyfonate (Fonofos or Fonophos)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Fonofos.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Fonofos is the maximum acceptable toxicant concentration (MATC) of 0.45 ug/L. The MATC is calculated as the geometric mean of the lowest observed effect concentration (LOEC) of 0.64 ug/L and the no observed effect concentration (NOEC) of 0.31 ug/L, as determined in a 21 day toxicity study with the water flea, Daphnia magna. Threshold values (LOEC and NOEC) are from USEPA Office of Pesticide Programs Ecotoxicity database.
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109294, Dyfonate (Fonofos or Fonophos)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166817
 
Pollutant: Dyfonate (Fonofos or Fonophos)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Fonofos.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Fonofos is the maximum acceptable toxicant concentration (MATC) of 0.45 ug/L. The MATC is calculated as the geometric mean of the lowest observed effect concentration (LOEC) of 0.64 ug/L and the no observed effect concentration (NOEC) of 0.31 ug/L, as determined in a 21 day toxicity study with the water flea, Daphnia magna. Threshold values (LOEC and NOEC) are from USEPA Office of Pesticide Programs Ecotoxicity database.
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109294, Dyfonate (Fonofos or Fonophos)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166813
 
Pollutant: Dyfonate (Fonofos or Fonophos)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Fonofos.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Fonofos is the maximum acceptable toxicant concentration (MATC) of 0.45 ug/L. The MATC is calculated as the geometric mean of the lowest observed effect concentration (LOEC) of 0.64 ug/L and the no observed effect concentration (NOEC) of 0.31 ug/L, as determined in a 21 day toxicity study with the water flea, Daphnia magna. Threshold values (LOEC and NOEC) are from USEPA Office of Pesticide Programs Ecotoxicity database.
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109295
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Endrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) list under section 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment. The pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the Section 303(d) list.

Eight lines of evidence (LOEs) are available in the administrative record to assess this pollutant.
Sample and exceedance counts for the lines of evidence with the fraction identified as “none” or “not recorded” are grouped together with those having the fraction “total”, based on the analytical method used. The following is a summary of the sample and exceedances for each beneficial use:

Zero of seven sediment samples exceed the aquatic life evaluation guideline. This sample size is insufficient to determine an applicable beneficial use support rating with the power and confidence of the Listing Policy. In accordance with Table 3.1 of the Listing Policy, a minimum of 16 samples is needed to determine if a beneficial use is fully supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:

1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero samples exceed the evaluation guideline and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109295, Endrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 16607
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Endrin.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for endrin is 207 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109295, Endrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 16608
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Endrin.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for endrin is 207 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109295, Endrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57866
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Endrin.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for sum of endrin is 207 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109295, Endrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57865
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Endrin.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for sum of endrin is 207 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109295, Endrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 153870
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Endrin .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Endrin from MacDonald et al., 2000a which states that the probable effect concentration for Endrin is 207 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109295, Endrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 153676
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Endrin .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Endrin from MacDonald et al., 2000a which states that the probable effect concentration for Endrin is 207 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109295, Endrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 16391
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Endrin.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for endrin is 207 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109295, Endrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 16390
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Endrin.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for endrin is 207 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
 
DECISION ID
109340
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Esfenvalerate/Fenvalerate
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment. The pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the Section 303(d) List.

Six lines of evidence are available in the administrative record to assess this pollutant.

Zero of the six sediment samples exceed the evaluation guideline applied to protect for aquatic life beneficial uses.
A minimum of 16 samples is needed to determine if a beneficial use is supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported using table 3.1 of the Listing Policy. Therefore, the use support rating is set to 'insufficient information'.
After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List.
This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the six sediment samples exceed the evaluation guideline applied to protect for aquatic life beneficial uses and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109340, Esfenvalerate/Fenvalerate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57872
 
Pollutant: Esfenvalerate/Fenvalerate
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Esfenvalerate/Fenvalerate, total.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for esfenvalerate/fenvalerate is the median lethal concentration (LC50) of 1.5 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.5 ug/g is the geometric mean of LC50 values for esfenvalerate/fenvalerate from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109340, Esfenvalerate/Fenvalerate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 148441
 
Pollutant: Esfenvalerate/Fenvalerate
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends Project (SPoT) data for San Luis Obispo Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Esfenvalerate/Fenvalerate, Total.
Data Reference: SPoT sediment data: 6/5/2018--6/13/2018.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for esfenvalerate/fenvalerate is the median lethal concentration (LC50) of 1.5 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.5 ug/g is the geometric mean of LC50 values for esfenvalerate/fenvalerate from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB
Temporal Representation: Data for this waterbody were collected on 06/13/2018.
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAPP and the SWAMP-SPoT QAPP. QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109340, Esfenvalerate/Fenvalerate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 148440
 
Pollutant: Esfenvalerate/Fenvalerate
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends Project (SPoT) data for San Luis Obispo Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Esfenvalerate/Fenvalerate, Total.
Data Reference: SPoT sediment data: 6/5/2018--6/13/2018.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for esfenvalerate/fenvalerate is the median lethal concentration (LC50) of 1.5 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.5 ug/g is the geometric mean of LC50 values for esfenvalerate/fenvalerate from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB
Temporal Representation: Data for this waterbody were collected on 06/13/2018.
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAPP and the SWAMP-SPoT QAPP. QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109340, Esfenvalerate/Fenvalerate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 154159
 
Pollutant: Esfenvalerate/Fenvalerate
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Esfenvalerate/Fenvalerate, Total .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for esfenvalerate/fenvalerate is the median lethal concentration (LC50) of 1.5 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.5 ug/g is the geometric mean of LC50 values for esfenvalerate/fenvalerate from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2011-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109340, Esfenvalerate/Fenvalerate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 154215
 
Pollutant: Esfenvalerate/Fenvalerate
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Esfenvalerate/Fenvalerate, Total .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for esfenvalerate/fenvalerate is the median lethal concentration (LC50) of 1.5 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.5 ug/g is the geometric mean of LC50 values for esfenvalerate/fenvalerate from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2011-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109340, Esfenvalerate/Fenvalerate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57873
 
Pollutant: Esfenvalerate/Fenvalerate
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Esfenvalerate/Fenvalerate, total.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for esfenvalerate/fenvalerate is the median lethal concentration (LC50) of 1.5 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.5 ug/g is the geometric mean of LC50 values for esfenvalerate/fenvalerate from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
 
DECISION ID
109322
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Ethion
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 109322, Ethion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 165707
 
Pollutant: Ethion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Ethion.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The USEPA expected safe lifetime exposure limit in drinking water for Ethion, calculated using the IRIS Reference Dose, is 3.5 ug/L. This was calculated assuming 70 kg body weight, 2 liters/day water consumption, 20% relative source contribution from drinking water, and 0.0005 mg/kg/day as the reference dose.
Guideline Reference: IRIS Reference Summary (Various Pollutants)
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109322, Ethion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 165646
 
Pollutant: Ethion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Ethion. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Ethion is the USEPA Aquatic Life Benchmark of 0.028 ug/L for invertebrates (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Date for this waterbody was collected over the date range 2010-07-21 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109322, Ethion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 165877
 
Pollutant: Ethion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Ethion.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The USEPA expected safe lifetime exposure limit in drinking water for Ethion, calculated using the IRIS Reference Dose, is 3.5 ug/L. This was calculated assuming 70 kg body weight, 2 liters/day water consumption, 20% relative source contribution from drinking water, and 0.0005 mg/kg/day as the reference dose.
Guideline Reference: IRIS Reference Summary (Various Pollutants)
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109322, Ethion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 165915
 
Pollutant: Ethion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Ethion. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Ethion is the USEPA Aquatic Life Benchmark of 0.028 ug/L for invertebrates (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM).
Temporal Representation: Date for this waterbody was collected over the date range 2015-09-09 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109322, Ethion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 165689
 
Pollutant: Ethion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Ethion. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Ethion is the USEPA Aquatic Life Benchmark of 0.028 ug/L for invertebrates (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV).
Temporal Representation: Date for this waterbody was collected over the date range 2015-05-20 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109322, Ethion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 165873
 
Pollutant: Ethion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Ethion. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Ethion is the USEPA Aquatic Life Benchmark of 0.028 ug/L for invertebrates (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Date for this waterbody was collected over the date range 2010-07-21 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109322, Ethion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 165934
 
Pollutant: Ethion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Ethion.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The USEPA expected safe lifetime exposure limit in drinking water for Ethion, calculated using the IRIS Reference Dose, is 3.5 ug/L. This was calculated assuming 70 kg body weight, 2 liters/day water consumption, 20% relative source contribution from drinking water, and 0.0005 mg/kg/day as the reference dose.
Guideline Reference: IRIS Reference Summary (Various Pollutants)
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109322, Ethion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 165957
 
Pollutant: Ethion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Ethion. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Ethion is the USEPA Aquatic Life Benchmark of 0.028 ug/L for invertebrates (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM).
Temporal Representation: Date for this waterbody was collected over the date range 2015-09-09 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109322, Ethion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 165750
 
Pollutant: Ethion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Ethion. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Ethion is the USEPA Aquatic Life Benchmark of 0.028 ug/L for invertebrates (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV).
Temporal Representation: Date for this waterbody was collected over the date range 2015-05-20 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109328
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Ethoprop
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the Clean Water Act (CWA) section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

A total of eight lines of evidence are available in the administrative record to assess this pollutant. A total of zero of 10 samples exceed the water quality objective for the cold freshwater habitat beneficial use and zero of 10 samples exceed the evaluation guideline for the warm freshwater habitat beneficial use. These data are insufficient to determine the applicable beneficial use support rating with the power and confidence required by the Listing Policy.

After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. A total of zero of 10 samples exceed the water quality objective for the cold freshwater habitat beneficial use and zero of 10 samples exceed the evaluation guideline for the warm freshwater habitat beneficial use. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 109328, Ethoprop
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166054
 
Pollutant: Ethoprop
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP SpecialStudies data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ethoprop.
Data Reference: Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Ethoprop is the USEPA Aquatic Life Benchmark of 0.8 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2018-01-17 and 2018-01-17
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109328, Ethoprop
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166131
 
Pollutant: Ethoprop
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Ethoprop.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Ethoprop is the USEPA Aquatic Life Benchmark of 0.8 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109328, Ethoprop
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 165883
 
Pollutant: Ethoprop
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP SpecialStudies data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ethoprop.
Data Reference: Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Ethoprop is the USEPA Aquatic Life Benchmark of 0.8 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2018-01-17 and 2018-01-17
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109328, Ethoprop
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 165880
 
Pollutant: Ethoprop
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Ethoprop.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Ethoprop is the USEPA Aquatic Life Benchmark of 0.8 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109328, Ethoprop
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166128
 
Pollutant: Ethoprop
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Ethoprop.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Ethoprop is the USEPA Aquatic Life Benchmark of 0.8 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109328, Ethoprop
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166097
 
Pollutant: Ethoprop
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Ethoprop.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Ethoprop is the USEPA Aquatic Life Benchmark of 0.8 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109328, Ethoprop
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166146
 
Pollutant: Ethoprop
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Ethoprop.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Ethoprop is the USEPA Aquatic Life Benchmark of 0.8 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109328, Ethoprop
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166218
 
Pollutant: Ethoprop
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Ethoprop.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Ethoprop is the USEPA Aquatic Life Benchmark of 0.8 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109332
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Fenitrothion
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 109332, Fenitrothion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166207
 
Pollutant: Fenitrothion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Fenitrothion.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Fenitrothion is the USEPA Aquatic Life Benchmark of 0.087 ug/L for an invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109332, Fenitrothion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166187
 
Pollutant: Fenitrothion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Fenitrothion.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Fenitrothion is the USEPA Aquatic Life Benchmark of 0.087 ug/L for an invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109332, Fenitrothion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166155
 
Pollutant: Fenitrothion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Fenitrothion.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Fenitrothion is the USEPA Aquatic Life Benchmark of 0.087 ug/L for an invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109332, Fenitrothion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166156
 
Pollutant: Fenitrothion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Fenitrothion.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Fenitrothion is the USEPA Aquatic Life Benchmark of 0.087 ug/L for an invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109332, Fenitrothion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166133
 
Pollutant: Fenitrothion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Fenitrothion.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Fenitrothion is the USEPA Aquatic Life Benchmark of 0.087 ug/L for an invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109332, Fenitrothion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 165991
 
Pollutant: Fenitrothion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Fenitrothion.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Fenitrothion is the USEPA Aquatic Life Benchmark of 0.087 ug/L for an invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109339
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Fenpropathrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 at least one line of evidence is necessary to assess listing status, but under section 3.6 at least two lines of evidence are necessary to assess listing status and the pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the section 303(d) List.

12 lines of evidence are available in the administrative record to assess this pollutant. Zero of six sediment samples exceed the evaluation guideline and zero of seven water samples exceed the evaluation guideline used to interpret the narrative water quality objective for aquatic life protection. This sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported using table 3.1. Therefore, the use support rating is set to 'insufficient information'.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the samples exceed the evaluation guidelines and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109339, Fenpropathrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166574
 
Pollutant: Fenpropathrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Fenpropathrin.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Fenpropathrin is the USEPA Aquatic Life Benchmark of 0.06 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109339, Fenpropathrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 148442
 
Pollutant: Fenpropathrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends Project (SPoT) data for San Luis Obispo Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Fenpropathrin.
Data Reference: SPoT sediment data: 6/5/2018--6/13/2018.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for fenpropathrin is the median lethal concentration (LC50) of 1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1 ug/g is the geometric mean of LC50 values for fenpropathrin from Ding et al. ( 2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB
Temporal Representation: Data for this waterbody were collected on 06/13/2018.
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAPP and the SWAMP-SPoT QAPP. QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109339, Fenpropathrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166479
 
Pollutant: Fenpropathrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Fenpropathrin.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Fenpropathrin is the USEPA Aquatic Life Benchmark of 0.06 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109339, Fenpropathrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 148443
 
Pollutant: Fenpropathrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends Project (SPoT) data for San Luis Obispo Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Fenpropathrin.
Data Reference: SPoT sediment data: 6/5/2018--6/13/2018.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for fenpropathrin is the median lethal concentration (LC50) of 1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1 ug/g is the geometric mean of LC50 values for fenpropathrin from Ding et al. ( 2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB
Temporal Representation: Data for this waterbody were collected on 06/13/2018.
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAPP and the SWAMP-SPoT QAPP. QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109339, Fenpropathrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166021
 
Pollutant: Fenpropathrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Fenpropathrin.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Fenpropathrin is the USEPA Aquatic Life Benchmark of 0.06 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109339, Fenpropathrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166573
 
Pollutant: Fenpropathrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Fenpropathrin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Fenpropathrin is the USEPA Aquatic Life Benchmark of 0.06 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109339, Fenpropathrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 154187
 
Pollutant: Fenpropathrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Fenpropathrin .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for fenpropathrin is the median lethal concentration (LC50) of 1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1 ug/g is the geometric mean of LC50 values for fenpropathrin from Ding et al. ( 2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2011-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109339, Fenpropathrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166551
 
Pollutant: Fenpropathrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Fenpropathrin.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Fenpropathrin is the USEPA Aquatic Life Benchmark of 0.06 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109339, Fenpropathrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57875
 
Pollutant: Fenpropathrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Fenpropathrin.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for fenpropathrin is the median lethal concentration (LC50) of 1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1 ug/g is the geometric mean of LC50 values for fenpropathrin from Ding et al. ( 2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109339, Fenpropathrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57874
 
Pollutant: Fenpropathrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Fenpropathrin.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for fenpropathrin is the median lethal concentration (LC50) of 1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1 ug/g is the geometric mean of LC50 values for fenpropathrin from Ding et al. ( 2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109339, Fenpropathrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 153967
 
Pollutant: Fenpropathrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Fenpropathrin .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for fenpropathrin is the median lethal concentration (LC50) of 1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1 ug/g is the geometric mean of LC50 values for fenpropathrin from Ding et al. ( 2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2011-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109339, Fenpropathrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166460
 
Pollutant: Fenpropathrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Fenpropathrin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Fenpropathrin is the USEPA Aquatic Life Benchmark of 0.06 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109333
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Fenthion
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 109333, Fenthion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166651
 
Pollutant: Fenthion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Fenthion. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Fenthion is the USEPA Aquatic Life Benchmark of 0.013 ug/L for an invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Date for this waterbody was collected over the date range 2010-07-21 to 2013-06-19
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109333, Fenthion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166622
 
Pollutant: Fenthion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP SpecialStudies data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Fenthion.
Data Reference: Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Fenthion is the USEPA Aquatic Life Benchmark of 0.013 ug/L for an invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2018-01-17 and 2018-01-17
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109333, Fenthion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166603
 
Pollutant: Fenthion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Fenthion. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Fenthion is the USEPA Aquatic Life Benchmark of 0.013 ug/L for an invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Date for this waterbody was collected over the date range 2010-07-21 to 2013-06-19
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109333, Fenthion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166361
 
Pollutant: Fenthion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP SpecialStudies data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Fenthion.
Data Reference: Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Fenthion is the USEPA Aquatic Life Benchmark of 0.013 ug/L for an invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2018-01-17 and 2018-01-17
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109321
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Fipronil
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 at least one line of evidence is necessary to assess listing status, but under section 3.6 at least two lines of evidence are necessary to assess listing status and the pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the section 303(d) List.

Eight lines of evidence are available in the administrative record to assess this pollutant.

Zero of one sediment samples exceed the evaluation guideline and zero of five water samples exceed the evaluation guideline used to interpret the narrative water quality objective for aquatic life protection. This sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported using table 3.1. Therefore, the use support rating is set to 'insufficient information'.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the samples exceed the evaluation guidelines and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 109321, Fipronil
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166518
 
Pollutant: Fipronil
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Fipronil.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the four-day average concentration of fipronil does not exceed 0.0032 ug/L (3.2 ng/L) in the water column more than once every three years on average (Bower, et al. 2017).
Guideline Reference: Water and Sediment Quality Criteria Report for Fipronil. Phase III: Application of the pesticide water and sediment quality criteria methodologies. Department of Environmental Toxicology, University of California, Davis.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109321, Fipronil
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166540
 
Pollutant: Fipronil
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Fipronil.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the four-day average concentration of fipronil does not exceed 0.0032 ug/L (3.2 ng/L) in the water column more than once every three years on average (Bower, et al. 2017).
Guideline Reference: Water and Sediment Quality Criteria Report for Fipronil. Phase III: Application of the pesticide water and sediment quality criteria methodologies. Department of Environmental Toxicology, University of California, Davis.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2015-11-16 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109321, Fipronil
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166585
 
Pollutant: Fipronil
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Fipronil.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the four-day average concentration of fipronil does not exceed 0.0032 ug/L (3.2 ng/L) in the water column more than once every three years on average (Bower, et al. 2017).
Guideline Reference: Water and Sediment Quality Criteria Report for Fipronil. Phase III: Application of the pesticide water and sediment quality criteria methodologies. Department of Environmental Toxicology, University of California, Davis.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109321, Fipronil
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 154350
 
Pollutant: Fipronil
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Fipronil .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for fipronil is the median lethal concentration (LC50) of 0.13 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Maul et al. 2008).
Guideline Reference: Effect of sediment-associated pyrethroids, fipronil, and metabolites on Chironomus tentans growth rate, body mass, condition index, immobilization, and survival. Environ. Toxicol. Chem. 27(12):2582-2590.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2015-05-27 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109321, Fipronil
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166605
 
Pollutant: Fipronil
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Fipronil.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the four-day average concentration of fipronil does not exceed 0.0032 ug/L (3.2 ng/L) in the water column more than once every three years on average (Bower, et al. 2017).
Guideline Reference: Water and Sediment Quality Criteria Report for Fipronil. Phase III: Application of the pesticide water and sediment quality criteria methodologies. Department of Environmental Toxicology, University of California, Davis.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109321, Fipronil
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 154452
 
Pollutant: Fipronil
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Fipronil .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for fipronil is the median lethal concentration (LC50) of 0.13 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Maul et al. 2008).
Guideline Reference: Effect of sediment-associated pyrethroids, fipronil, and metabolites on Chironomus tentans growth rate, body mass, condition index, immobilization, and survival. Environ. Toxicol. Chem. 27(12):2582-2590.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2015-05-27 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109321, Fipronil
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166563
 
Pollutant: Fipronil
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Fipronil.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the four-day average concentration of fipronil does not exceed 0.0032 ug/L (3.2 ng/L) in the water column more than once every three years on average (Bower, et al. 2017).
Guideline Reference: Water and Sediment Quality Criteria Report for Fipronil. Phase III: Application of the pesticide water and sediment quality criteria methodologies. Department of Environmental Toxicology, University of California, Davis.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109321, Fipronil
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166583
 
Pollutant: Fipronil
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Fipronil.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the four-day average concentration of fipronil does not exceed 0.0032 ug/L (3.2 ng/L) in the water column more than once every three years on average (Bower, et al. 2017).
Guideline Reference: Water and Sediment Quality Criteria Report for Fipronil. Phase III: Application of the pesticide water and sediment quality criteria methodologies. Department of Environmental Toxicology, University of California, Davis.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2015-11-16 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109280
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Fipronil Desulfinyl
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 109280, Fipronil Desulfinyl
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166521
 
Pollutant: Fipronil Desulfinyl
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Fipronil Desulfinyl.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Fipronil degradate Fipronil desulfinyl is the USEPA Aquatic Life Benchmark of 0.54 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109280, Fipronil Desulfinyl
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166454
 
Pollutant: Fipronil Desulfinyl
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Fipronil Desulfinyl.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Fipronil degradate Fipronil desulfinyl is the USEPA Aquatic Life Benchmark of 0.54 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109280, Fipronil Desulfinyl
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166453
 
Pollutant: Fipronil Desulfinyl
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Fipronil Desulfinyl.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Fipronil degradate Fipronil desulfinyl is the USEPA Aquatic Life Benchmark of 0.54 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2015-11-16 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109280, Fipronil Desulfinyl
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166499
 
Pollutant: Fipronil Desulfinyl
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Fipronil Desulfinyl.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Fipronil degradate Fipronil desulfinyl is the USEPA Aquatic Life Benchmark of 0.54 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2015-11-16 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109280, Fipronil Desulfinyl
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166409
 
Pollutant: Fipronil Desulfinyl
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Fipronil Desulfinyl.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Fipronil degradate Fipronil desulfinyl is the USEPA Aquatic Life Benchmark of 0.54 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109280, Fipronil Desulfinyl
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 166410
 
Pollutant: Fipronil Desulfinyl
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Fipronil Desulfinyl.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Fipronil degradate Fipronil desulfinyl is the USEPA Aquatic Life Benchmark of 0.54 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109341
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Fipronil Sulfide
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 109341, Fipronil Sulfide
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 154529
 
Pollutant: Fipronil Sulfide
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Fipronil Sulfide .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for fipronil sulfide is the median lethal concentration (LC50) of 0.16 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Maul et al. 2008).
Guideline Reference: Effect of sediment-associated pyrethroids, fipronil, and metabolites on Chironomus tentans growth rate, body mass, condition index, immobilization, and survival. Environ. Toxicol. Chem. 27(12):2582-2590.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2015-05-27 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109341, Fipronil Sulfide
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 154314
 
Pollutant: Fipronil Sulfide
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Fipronil Sulfide .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for fipronil sulfide is the median lethal concentration (LC50) of 0.16 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Maul et al. 2008).
Guideline Reference: Effect of sediment-associated pyrethroids, fipronil, and metabolites on Chironomus tentans growth rate, body mass, condition index, immobilization, and survival. Environ. Toxicol. Chem. 27(12):2582-2590.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2015-05-27 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109342
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Fipronil Sulfone
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 109342, Fipronil Sulfone
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 154536
 
Pollutant: Fipronil Sulfone
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Fipronil Sulfone .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for fipronil sulfone is the median lethal concentration (LC50) of 0.12 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Maul et al. 2008).
Guideline Reference: Effect of sediment-associated pyrethroids, fipronil, and metabolites on Chironomus tentans growth rate, body mass, condition index, immobilization, and survival. Environ. Toxicol. Chem. 27(12):2582-2590.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2015-05-27 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109342, Fipronil Sulfone
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 154497
 
Pollutant: Fipronil Sulfone
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Fipronil Sulfone .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for fipronil sulfone is the median lethal concentration (LC50) of 0.12 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Maul et al. 2008).
Guideline Reference: Effect of sediment-associated pyrethroids, fipronil, and metabolites on Chironomus tentans growth rate, body mass, condition index, immobilization, and survival. Environ. Toxicol. Chem. 27(12):2582-2590.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2015-05-27 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109296
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Fluoranthene
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) list under section 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment. The pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the Section 303(d) list.

Six lines of evidence (LOEs) are available in the administrative record to assess this pollutant.
Sample and exceedance counts for the lines of evidence with the fraction identified as “none” or “not recorded” are grouped together with those having the fraction “total”, based on the analytical method used. The following is a summary of the sample and exceedances for each beneficial use:

Zero of four sediment samples exceed the aquatic life evaluation guideline. This sample size is insufficient to determine an applicable beneficial use support rating with the power and confidence of the Listing Policy. In accordance with Table 3.1 of the Listing Policy, a minimum of 16 samples is needed to determine if a beneficial use is fully supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:

1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero samples exceed the evaluation guideline and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109296, Fluoranthene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 16459
 
Pollutant: Fluoranthene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Fluoranthene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for Fluoranthene is 2,230 ug/Kg dry weight (Macdonald et al. 2000)
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109296, Fluoranthene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 16844
 
Pollutant: Fluoranthene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Fluoranthene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for Fluoranthene is 2,230 ug/Kg dry weight (Macdonald et al. 2000)
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109296, Fluoranthene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 16460
 
Pollutant: Fluoranthene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Fluoranthene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for Fluoranthene is 2,230 ug/Kg dry weight (Macdonald et al. 2000)
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109296, Fluoranthene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 16858
 
Pollutant: Fluoranthene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Fluoranthene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for Fluoranthene is 2,230 ug/Kg dry weight (Macdonald et al. 2000)
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109296, Fluoranthene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 154278
 
Pollutant: Fluoranthene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Fluoranthene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for fluoranthene is 2,230 ug/kg dry weight (MacDonald et al 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109296, Fluoranthene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 154260
 
Pollutant: Fluoranthene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Fluoranthene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for fluoranthene is 2,230 ug/kg dry weight (MacDonald et al 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109297
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Fluorene
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) list under section 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment. The pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the Section 303(d) list.

Six lines of evidence (LOEs) are available in the administrative record to assess this pollutant.
Sample and exceedance counts for the lines of evidence with the fraction identified as “none” or “not recorded” are grouped together with those having the fraction “total”, based on the analytical method used. The following is a summary of the sample and exceedances for each beneficial use:

Zero of four sediment samples exceed the aquatic life evaluation guideline. This sample size is insufficient to determine an applicable beneficial use support rating with the power and confidence of the Listing Policy. In accordance with Table 3.1 of the Listing Policy, a minimum of 16 samples is needed to determine if a beneficial use is fully supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:

1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero samples exceed the evaluation guideline and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109297, Fluorene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 16569
 
Pollutant: Fluorene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Fluorene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for fluorene is 536 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109297, Fluorene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 17340
 
Pollutant: Fluorene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Fluorene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for fluorene is 536 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109297, Fluorene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 17341
 
Pollutant: Fluorene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Fluorene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for fluorene is 536 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109297, Fluorene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 16570
 
Pollutant: Fluorene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Fluorene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for fluorene is 536 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109297, Fluorene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 154342
 
Pollutant: Fluorene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Fluorene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Fluorene from MacDonald et al., 2000a which states that the probable effect concentration for Fluorene is 536 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109297, Fluorene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 154379
 
Pollutant: Fluorene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Fluorene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Fluorene from MacDonald et al., 2000a which states that the probable effect concentration for Fluorene is 536 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109323
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Imidacloprid
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 109323, Imidacloprid
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 167080
 
Pollutant: Imidacloprid
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Imidacloprid. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the 4-day average concentration of Imidacloprid does not exceed 0.016 ug/L. (UC Davis Water Quality Criteria)
Guideline Reference: Water Quality Criteria Report for Imidacloprid Phase III: Application of the pesticide water quality criteria methodology. Department of Environmental Toxicology. University of California, Davis
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM).
Temporal Representation: Date for this waterbody was collected over the date range 2015-09-09 to 2015-09-09
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109323, Imidacloprid
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 167169
 
Pollutant: Imidacloprid
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Imidacloprid.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the 4-day average concentration of Imidacloprid does not exceed 0.016 ug/L. (UC Davis Water Quality Criteria)
Guideline Reference: Water Quality Criteria Report for Imidacloprid Phase III: Application of the pesticide water quality criteria methodology. Department of Environmental Toxicology. University of California, Davis
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-09-09
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109323, Imidacloprid
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 167127
 
Pollutant: Imidacloprid
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Imidacloprid.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the 4-day average concentration of Imidacloprid does not exceed 0.016 ug/L. (UC Davis Water Quality Criteria)
Guideline Reference: Water Quality Criteria Report for Imidacloprid Phase III: Application of the pesticide water quality criteria methodology. Department of Environmental Toxicology. University of California, Davis
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-09-09
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109323, Imidacloprid
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 167228
 
Pollutant: Imidacloprid
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Imidacloprid. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the 4-day average concentration of Imidacloprid does not exceed 0.016 ug/L. (UC Davis Water Quality Criteria)
Guideline Reference: Water Quality Criteria Report for Imidacloprid Phase III: Application of the pesticide water quality criteria methodology. Department of Environmental Toxicology. University of California, Davis
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM).
Temporal Representation: Date for this waterbody was collected over the date range 2015-09-09 to 2015-09-09
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109343
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Iprodione
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 109343, Iprodione
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 167390
 
Pollutant: Iprodione
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Iprodione.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Iprodione is the USEPA Aquatic Life Benchmark of 120 ug/L for an invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109343, Iprodione
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 167413
 
Pollutant: Iprodione
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Iprodione.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Based on USEPA IRIS reference dose (RfD) as a drinking water level, the drinking water health advisory level for Iprodione is 280 ug/L. This was calculated assuming 70 kg body weight, 2 liters/day water consumption, and 20% relative source contribution from drinking water with 0.04 mg/kg/day as the reference dose. An additional uncertainty factor of 10 is used for Class C carcinogens
Guideline Reference: IRIS Summary for Iprodione
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109343, Iprodione
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 167388
 
Pollutant: Iprodione
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Iprodione.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Iprodione is the USEPA Aquatic Life Benchmark of 120 ug/L for an invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109343, Iprodione
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 167411
 
Pollutant: Iprodione
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Iprodione.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Iprodione is the USEPA Aquatic Life Benchmark of 120 ug/L for an invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109343, Iprodione
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 167369
 
Pollutant: Iprodione
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Iprodione.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Based on USEPA IRIS reference dose (RfD) as a drinking water level, the drinking water health advisory level for Iprodione is 280 ug/L. This was calculated assuming 70 kg body weight, 2 liters/day water consumption, and 20% relative source contribution from drinking water with 0.04 mg/kg/day as the reference dose. An additional uncertainty factor of 10 is used for Class C carcinogens
Guideline Reference: IRIS Summary for Iprodione
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109343, Iprodione
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 167371
 
Pollutant: Iprodione
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Iprodione.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Iprodione is the USEPA Aquatic Life Benchmark of 120 ug/L for an invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109343, Iprodione
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 167367
 
Pollutant: Iprodione
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Iprodione.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Iprodione is the USEPA Aquatic Life Benchmark of 120 ug/L for an invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109343, Iprodione
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 167410
 
Pollutant: Iprodione
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Iprodione.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Based on USEPA IRIS reference dose (RfD) as a drinking water level, the drinking water health advisory level for Iprodione is 280 ug/L. This was calculated assuming 70 kg body weight, 2 liters/day water consumption, and 20% relative source contribution from drinking water with 0.04 mg/kg/day as the reference dose. An additional uncertainty factor of 10 is used for Class C carcinogens
Guideline Reference: IRIS Summary for Iprodione
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109343, Iprodione
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 167412
 
Pollutant: Iprodione
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Iprodione.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Iprodione is the USEPA Aquatic Life Benchmark of 120 ug/L for an invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109300
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) list under section 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment. The pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the Section 303(d) list.

Four lines of evidence (LOEs) are available in the administrative record to assess this pollutant.

Zero of three sediment samples exceed the aquatic life evaluation guideline. This sample size is insufficient to determine an applicable beneficial use support rating with the power and confidence of the Listing Policy. In accordance with Table 3.1 of the Listing Policy, a minimum of 16 samples is needed to determine if a beneficial use is fully supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:

1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero samples exceed the evaluation guideline and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109300, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57884
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for HCH, gamma.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for Lindane (gamma-HCH) is 4.99 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109300, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 154719
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for HCH, gamma-. Although a total of 5 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Lindane from MacDonald et al., 2000a which states that the probable effect concentration for Lindane is 4.99 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109300, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 154720
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for HCH, gamma-. Although a total of 5 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Lindane from MacDonald et al., 2000a which states that the probable effect concentration for Lindane is 4.99 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109300, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57883
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for HCH, gamma.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for Lindane (gamma-HCH) is 4.99 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
 
DECISION ID
109301
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Malathion
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Twelve lines of evidence are available in the administrative record to assess this pollutant. Zero of one sample exceed the evaluation guideline (Faria et al., 2010) applied to protect aquatic life beneficial uses. Zero of 10 samples exceed the evaluation guideline for drinking water (USEPA drinking water health advisory). These sample sizes are insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.

After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List because applicable water quality standards are not being exceeded.

This conclusion is based on the staff findings that:

1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.

2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.

3. Zero samples exceeded the evaluation guidelines and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. These sample sizes are insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 109301, Malathion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 169099
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP SpecialStudies data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Malathion.
Data Reference: Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The USEPA drinking water health advisory for malathion is 500 ug/L.
Guideline Reference: 2018 Edition of the Drinking Water Standards and Health Advisories
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2018-01-17 and 2018-01-17
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109301, Malathion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 168908
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Malathion. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of malathion does not exceed 0.028 ug/L more than once every three years on the average (Faria et al., 2010).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: l. Organophosphate insecticides. Reviews of Environmental Contamination and Toxicology 216:1-48.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Date for this waterbody was collected over the date range 2010-07-21 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109301, Malathion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 168909
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Malathion.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The USEPA drinking water health advisory for malathion is 500 ug/L.
Guideline Reference: 2018 Edition of the Drinking Water Standards and Health Advisories
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109301, Malathion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 168885
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Malathion. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of malathion does not exceed 0.028 ug/L more than once every three years on the average (Faria et al., 2010).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: l. Organophosphate insecticides. Reviews of Environmental Contamination and Toxicology 216:1-48.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM).
Temporal Representation: Date for this waterbody was collected over the date range 2015-09-09 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109301, Malathion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 168442
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Malathion. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of malathion does not exceed 0.028 ug/L more than once every three years on the average (Faria et al., 2010).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: l. Organophosphate insecticides. Reviews of Environmental Contamination and Toxicology 216:1-48.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Date for this waterbody was collected over the date range 2010-07-21 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109301, Malathion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 168698
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Malathion. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of malathion does not exceed 0.028 ug/L more than once every three years on the average (Faria et al., 2010).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: l. Organophosphate insecticides. Reviews of Environmental Contamination and Toxicology 216:1-48.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV).
Temporal Representation: Date for this waterbody was collected over the date range 2015-05-20 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109301, Malathion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 169009
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Malathion.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The USEPA drinking water health advisory for malathion is 500 ug/L.
Guideline Reference: 2018 Edition of the Drinking Water Standards and Health Advisories
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109301, Malathion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 168634
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP SpecialStudies data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Malathion.
Data Reference: Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of malathion does not exceed 0.028 ug/L more than once every three years on the average (Faria et al., 2010).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: l. Organophosphate insecticides. Reviews of Environmental Contamination and Toxicology 216:1-48.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2018-01-17 and 2018-01-17
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109301, Malathion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 168929
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Malathion. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of malathion does not exceed 0.028 ug/L more than once every three years on the average (Faria et al., 2010).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: l. Organophosphate insecticides. Reviews of Environmental Contamination and Toxicology 216:1-48.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM).
Temporal Representation: Date for this waterbody was collected over the date range 2015-09-09 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109301, Malathion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 168958
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Malathion.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The USEPA drinking water health advisory for malathion is 500 ug/L.
Guideline Reference: 2018 Edition of the Drinking Water Standards and Health Advisories
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109301, Malathion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 168675
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Malathion. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of malathion does not exceed 0.028 ug/L more than once every three years on the average (Faria et al., 2010).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: l. Organophosphate insecticides. Reviews of Environmental Contamination and Toxicology 216:1-48.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV).
Temporal Representation: Date for this waterbody was collected over the date range 2015-05-20 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109301, Malathion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 168960
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP SpecialStudies data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Malathion.
Data Reference: Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of malathion does not exceed 0.028 ug/L more than once every three years on the average (Faria et al., 2010).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: l. Organophosphate insecticides. Reviews of Environmental Contamination and Toxicology 216:1-48.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2018-01-17 and 2018-01-17
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109302
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Manganese
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the Clean Water Act (CWA) section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

A total of three lines of evidence are available in the administrative record to assess this pollutant. A total of zero of 14 samples exceed the water quality objective for the agricultural supply beneficial use. These data are insufficient to determine the applicable beneficial use support rating with the power and confidence required by the Listing Policy.

After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. A total of zero of 14 samples exceed the water quality objective for the agricultural supply beneficial use. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 109302, Manganese
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 169061
 
Pollutant: Manganese
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Manganese.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan identified as the maximum concentration for manganese for irrigation supply as 0.2 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109302, Manganese
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 168746
 
Pollutant: Manganese
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Manganese.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan identified as the maximum concentration for manganese for irrigation supply as 0.2 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109302, Manganese
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 168867
 
Pollutant: Manganese
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Manganese.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan identified as the maximum concentration for manganese for irrigation supply as 0.2 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2013-06-10 and 2017-12-07
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
130762
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Mercury
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) List under section 3.1 and section 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment. The pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the 303(d) List.

Twenty-six lines of evidence are available in the administrative record to assess this pollutant.

Fifteen LOEs summarize water samples:
- Zero of eleven water samples exceed the mercury evaluation guideline (National Recommended Water Quality Criteria, EPA 2016), set to protect for aquatic life beneficial uses.
- Zero of eleven water samples exceed the mercury evaluation guideline (California Toxics Rule, 2000), set to protect for the commercial or recreational collection of fish, shellfish, or organisms beneficial use.
- Zero of eleven water samples exceed the mercury water quality objective (Basin Plan), set to protect for agricultural supply beneficial use.
- Zero of eleven water samples exceed the mercury evaluation guideline (California Toxics Rule, 2000), set to protect for the municipal and domestic supply beneficial use.

Eleven LOEs summarize sediment samples. Zero of ten sediment samples exceed the mercury evaluation guideline (MacDonald et al., 2000a) set to protect for aquatic life beneficial uses. Zero of one sediment sample exceeds the mercury evaluation guideline (PTI Environmental Services, 1991) set to protect for the estuarine habitat beneficial use. Note that sediment samples with ‘none’ and ‘total’ are summed for the purposes of this decision.

After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. No water or sediment samples exceeded the evaluation guidelines, and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 130762, Mercury
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 169150
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Mercury.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Human health risk associated with organism consumption is 0.051 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 130762, Mercury
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 169210
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Mercury.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents known to be deleterious to fish or wildlife (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The Criterion Continuous Concentration for freshwater aquatic life is 0.77 ug/L (National Recommended Water Quality Criteria, EPA 2016)
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2017-12-07
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 130762, Mercury
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 154837
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Mercury .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for mercury in 1.06 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2017-06-05
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 130762, Mercury
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 169506
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Mercury.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The mercury criteria for the protection of human health from the consumption of water and organisms for mercury is 0.050 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2017-12-07
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 130762, Mercury
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 169095
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Mercury.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents known to be deleterious to fish or wildlife (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The Criterion Continuous Concentration for freshwater aquatic life is 0.77 ug/L (National Recommended Water Quality Criteria, EPA 2016)
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2017-12-07
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 130762, Mercury
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 169019
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Mercury.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan and identified as the maximum concentration for mercury for livestock watering as 0.01 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 130762, Mercury
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 154858
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Mercury .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for mercury in 1.06 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2017-06-05
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 130762, Mercury
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 148446
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends Project (SPoT) data for San Luis Obispo Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Mercury.
Data Reference: SPoT sediment data: 6/5/2018--6/13/2018.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for mercury in 1.06 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB
Temporal Representation: Data for this waterbody were collected on 06/13/2018.
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAPP and the SWAMP-SPoT QAPP. QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 130762, Mercury
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 168925
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Mercury.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Human health risk associated with organism consumption is 0.051 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2017-12-07
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 130762, Mercury
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 169420
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Mercury.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan and identified as the maximum concentration for mercury for livestock watering as 0.01 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2017-12-07
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 130762, Mercury
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 148445
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Estuarine Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends Project (SPoT) data for San Luis Obispo Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Mercury.
Data Reference: SPoT sediment data: 6/5/2018--6/13/2018.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline used in this assessment comes form PTI Environmental Services, 1991, and is 2.1 ug/g.
Guideline Reference: An evaluation of methods for calculating mean sediment quality guideline quotients as indicators of contamination and acute toxicity to amphipods by chemical mixtures. Environmental Toxicology and Chemistry. 20(10): 2276-2286
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB
Temporal Representation: Data for this waterbody were collected on 06/13/2018.
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAPP and the SWAMP-SPoT QAPP. QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 130762, Mercury
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 169503
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Mercury.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents known to be deleterious to fish or wildlife (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The Criterion Continuous Concentration for freshwater aquatic life is 0.77 ug/L (National Recommended Water Quality Criteria, EPA 2016)
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 130762, Mercury
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 148444
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends Project (SPoT) data for San Luis Obispo Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Mercury.
Data Reference: SPoT sediment data: 6/5/2018--6/13/2018.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for mercury in 1.06 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB
Temporal Representation: Data for this waterbody were collected on 06/13/2018.
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAPP and the SWAMP-SPoT QAPP. QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 130762, Mercury
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 169416
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Mercury.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan and identified as the maximum concentration for mercury for livestock watering as 0.01 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 130762, Mercury
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 169473
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Mercury.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents known to be deleterious to fish or wildlife (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The Criterion Continuous Concentration for freshwater aquatic life is 0.77 ug/L (National Recommended Water Quality Criteria, EPA 2016)
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 130762, Mercury
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 169351
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Mercury.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Human health risk associated with organism consumption is 0.051 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 130762, Mercury
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 169304
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Mercury.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The mercury criteria for the protection of human health from the consumption of water and organisms for mercury is 0.050 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 130762, Mercury
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 17237
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 2 of 2 samples exceed the criterion for Mercury.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for mercury is 1.06 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130762, Mercury
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 17239
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Mercury.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for mercury is 1.06 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130762, Mercury
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 17240
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Mercury.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for mercury is 1.06 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130762, Mercury
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 17250
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 2 of 2 samples exceed the criterion for Mercury.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for mercury is 1.06 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130762, Mercury
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57893
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Mercury.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for mercury is 1.06 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 130762, Mercury
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57892
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Mercury.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for mercury is 1.06 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 130762, Mercury
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 169213
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Mercury.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The mercury criteria for the protection of human health from the consumption of water and organisms for mercury is 0.050 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 130762, Mercury
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 169344
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Mercury.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents known to be deleterious to fish or wildlife (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The Criterion Continuous Concentration for freshwater aquatic life is 0.77 ug/L (National Recommended Water Quality Criteria, EPA 2016)
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 130762, Mercury
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 168999
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Mercury.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents known to be deleterious to fish or wildlife (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The Criterion Continuous Concentration for freshwater aquatic life is 0.77 ug/L (National Recommended Water Quality Criteria, EPA 2016)
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109326
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Methidathion
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) List under sections 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Six lines of evidence are available in the administrative record to assess this pollutant. Zero of three water samples exceeded the USEPA aquatic life evaluation guideline. Zero of three water samples exceed the USEPA drinking water health advisory level for municipal and domestic water supply. These sample sizes are insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is supported using table 3.1.

After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List because applicable water quality standards are not being exceeded.

This conclusion is based on the staff findings that:

1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.

2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.

3. Zero samples exceed the evaluation guidelines. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.

4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 109326, Methidathion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 169748
 
Pollutant: Methidathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP SpecialStudies data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Methidathion.
Data Reference: Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Based on USEPA IRIS reference dose (RfD) as a drinking water level, the drinking water health advisory level for methidathion is 0.7 ug/L. This was calculated assuming 70 kg body weight, 2 liters/day water consumption, and 20% relative source contribution from drinking water. An additional uncertainty factor of 10 is used for Class C carcinogens.
Guideline Reference: IRIS Database Calculations (summary)
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2018-01-17 and 2018-01-17
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109326, Methidathion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 169702
 
Pollutant: Methidathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Methidathion.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Methidathion is the USEPA Aquatic Life Benchmark of 0.66 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2013-06-19
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109326, Methidathion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 169686
 
Pollutant: Methidathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP SpecialStudies data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Methidathion.
Data Reference: Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Methidathion is the USEPA Aquatic Life Benchmark of 0.66 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2018-01-17 and 2018-01-17
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109326, Methidathion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 169731
 
Pollutant: Methidathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Methidathion.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Methidathion is the USEPA Aquatic Life Benchmark of 0.66 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2013-06-19
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109326, Methidathion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 169808
 
Pollutant: Methidathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Methidathion.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Based on USEPA IRIS reference dose (RfD) as a drinking water level, the drinking water health advisory level for methidathion is 0.7 ug/L. This was calculated assuming 70 kg body weight, 2 liters/day water consumption, and 20% relative source contribution from drinking water. An additional uncertainty factor of 10 is used for Class C carcinogens.
Guideline Reference: IRIS Database Calculations (summary)
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2013-06-19
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109326, Methidathion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 169854
 
Pollutant: Methidathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP SpecialStudies data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Methidathion.
Data Reference: Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Methidathion is the USEPA Aquatic Life Benchmark of 0.66 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2018-01-17 and 2018-01-17
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109303
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Methyl Parathion
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment. The pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the Section 303(d) List.

Four lines of evidence are available in the administrative record to assess this pollutant. Zero of four sediment samples exceeded the aquatic life evaluation guideline (Ding, et. al., 2010). These sample sizes are insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is supported using table 3.1.

After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List because applicable water quality standards are not being exceeded.

This conclusion is based on the staff findings that:

1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.

2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.

3. Zero samples exceed the evaluation guidelines. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.

4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109303, Methyl Parathion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57895
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Parathion, Methyl.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for methyl parathion is the median lethal concentration (LC50) of 6 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 6 ug/g is the geometric mean of LC50 values for methyl parathion from Ding et al. (2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109303, Methyl Parathion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57894
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Parathion, Methyl.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for methyl parathion is the median lethal concentration (LC50) of 6 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 6 ug/g is the geometric mean of LC50 values for methyl parathion from Ding et al. (2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109303, Methyl Parathion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 155118
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Parathion, Methyl .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for methyl parathion is the median lethal concentration (LC50) of 6 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 6 ug/g is the geometric mean of LC50 values for methyl parathion from Ding et al. (2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2012-05-16
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109303, Methyl Parathion
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 155075
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Parathion, Methyl .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for methyl parathion is the median lethal concentration (LC50) of 6 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 6 ug/g is the geometric mean of LC50 values for methyl parathion from Ding et al. (2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2012-05-16
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109304
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Naphthalene
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) list under section 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment. The pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the Section 303(d) list.

Six lines of evidence (LOEs) are available in the administrative record to assess this pollutant.
Sample and exceedance counts for the lines of evidence with the fraction identified as “none” or “not recorded” are grouped together with those having the fraction “total”, based on the analytical method used. The following is a summary of the sample and exceedances for each beneficial use:

Zero of four sediment samples exceed the aquatic life evaluation guideline. This sample size is insufficient to determine an applicable beneficial use support rating with the power and confidence of the Listing Policy. In accordance with Table 3.1 of the Listing Policy, a minimum of 16 samples is needed to determine if a beneficial use is fully supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:

1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero samples exceed the evaluation guideline and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109304, Naphthalene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 155082
 
Pollutant: Naphthalene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Naphthalene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for naphthalene is 561 ug/kg dry weight (MacDonald et al. 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109304, Naphthalene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 155124
 
Pollutant: Naphthalene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Naphthalene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for naphthalene is 561 ug/kg dry weight (MacDonald et al. 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109304, Naphthalene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 17304
 
Pollutant: Naphthalene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Naphthalene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for naphthalene is 561 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109304, Naphthalene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 17075
 
Pollutant: Naphthalene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Naphthalene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for naphthalene is 561 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109304, Naphthalene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 17303
 
Pollutant: Naphthalene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Naphthalene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for naphthalene is 561 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109304, Naphthalene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 17074
 
Pollutant: Naphthalene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Naphthalene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for naphthalene is 561 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
 
DECISION ID
109305
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Nickel
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the Clean Water Act (CWA) section 303(d) List under section 3.1 and 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment. The pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the Section 303(d) List.

A total of 31 lines of evidence are available in the administrative record to assess this pollutant. Sample and exceedance counts for the lines of evidence with the fraction identified as “none” or “not recorded” are grouped together with those having the fraction “total”, based on the analytical method used. For the water matrix, a total of zero of 14 samples exceed the water quality objective for the agricultural supply beneficial use, zero of 14 samples exceed the water quality objective for the cold freshwater habitat beneficial use, zero of 14 samples exceed the water quality objective for the commercial or recreational collection of fish, shellfish, or organisms beneficial use and zero of 14 samples exceed the water quality objective for the warm freshwater habitat beneficial use. For the sediment matrix, a total of 10 of 10 samples exceed the evaluation guideline for the cold freshwater habitat beneficial use and 10 of 10 samples exceed the evaluation guideline for the warm freshwater habitat beneficial use but these samples are not associated with sediment toxicity. These data are insufficient to determine the applicable beneficial use support rating with the power and confidence required by the Listing Policy.

After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. For the water matrix, a total of zero of 14 samples exceed the water quality objective for the agricultural supply beneficial use, zero of 14 samples exceed the water quality objective for the cold freshwater habitat beneficial use, zero of 14 samples exceed the water quality objective for the commercial or recreational collection of fish, shellfish, or organisms beneficial use and zero of 14 samples exceed the water quality objective for the warm freshwater habitat beneficial use. For the sediment matrix, a total of 10 of 10 samples exceed the evaluation guideline for the cold freshwater habitat beneficial use and 10 of 10 samples exceed the evaluation guideline for the warm freshwater habitat beneficial use but these samples are not associated with sediment toxicity. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109305, Nickel
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57914
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to evaluate sediment toxicity. None of the samples exhibited significant toxicity. The toxicity tests included survival and growth of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Coastal Confluences 2008 2009
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 3 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
Guideline Reference: SWAMP_Memo_Toxicity_Data_Intrepretation
 
Spatial Representation: The samples were collected at station 310SLB - San Luis Creek at San Luis Bay Drive.
Temporal Representation: The samples were collected in May 2009.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2002) was followed.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109305, Nickel
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 148691
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 1 of the 8 samples collected by SWAMP Stream Pollution Trends for San Luis Obispo Creek (below Osos Street) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Growth (wt/surv indiv), Chironomus dilutus, for Survival, Hyalella azteca, for Survival, Chironomus dilutus, for Ash Free Dry Mass, Chironomus dilutus, for Growth (wt/surv indiv)
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Central Coastal Basin Plan 2019).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( 310SLB )
Temporal Representation: The samples were collected between the dates of 2010-06-21 and 2018-06-13.
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109305, Nickel
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 154961
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 7
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 7 of the 7 samples exceeded the evaluation guideline for Nickel .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for nickel in 48.6 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2018-06-13
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109305, Nickel
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 171372
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2013-06-10 and 2017-12-07
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109305, Nickel
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 171203
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109305, Nickel
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 170613
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109305, Nickel
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 23972
 
Pollutant: Invertebrate Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Toxicity, Hyalella azteca Survival (%) 10 days. Toxicity is defined by SWAMP (2004) as follows: Significant toxicity in the survival endpoint when compared to the negative control based on a statistical test with alpha of less than 5%, and less than the evaluation threshold (both criteria are met).
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Significant reduction of survival of test organism relative to the control (alpha < 0.05) and test organism survival is 20% less than the control survival.
Guideline Reference: Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109305, Nickel
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 23973
 
Pollutant: Invertebrate Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Toxicity, Hyalella azteca Survival (%) 10 days. Toxicity is defined by SWAMP (2004) as follows: Significant toxicity in the survival endpoint when compared to the negative control based on a statistical test with alpha of less than 5%, and less than the evaluation threshold (both criteria are met).
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Significant reduction of survival of test organism relative to the control (alpha < 0.05) and test organism survival is 20% less than the control survival.
Guideline Reference: Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109305, Nickel
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 170992
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109305, Nickel
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 16905
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Nickel.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for nickel is 48.6 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109305, Nickel
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 16884
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Nickel.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for nickel is 48.6 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109305, Nickel
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 16906
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Nickel.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for nickel is 48.6 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109305, Nickel
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 16885
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Nickel.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for nickel is 48.6 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109305, Nickel
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57902
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Nickel.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for nickel is 48.6 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109305, Nickel
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57901
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Nickel.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for nickel is 48.6 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109305, Nickel
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57917
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to evaluate sediment toxicity. None of the samples exhibited significant toxicity. The toxicity tests included survival and growth of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 3 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
Guideline Reference: SWAMP_Memo_Toxicity_Data_Intrepretation
 
Spatial Representation: The samples were collected at station 310SLBxxx.
Temporal Representation: The samples were collected in June 2008.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2002) was followed.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109305, Nickel
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 148677
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 1 of the 8 samples collected by SWAMP Stream Pollution Trends for San Luis Obispo Creek (below Osos Street) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Growth (wt/surv indiv), Chironomus dilutus, for Survival, Hyalella azteca, for Survival, Chironomus dilutus, for Ash Free Dry Mass, Chironomus dilutus, for Growth (wt/surv indiv)
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Central Coastal Basin Plan 2019).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( 310SLB )
Temporal Representation: The samples were collected between the dates of 2010-06-21 and 2018-06-13.
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109305, Nickel
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57915
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to evaluate sediment toxicity. None of the samples exhibited significant toxicity. The toxicity tests included survival and growth of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Santa Lucia Watershed Rotation 2009
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 3 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
Guideline Reference: SWAMP_Memo_Toxicity_Data_Intrepretation
 
Spatial Representation: The samples were collected at station 310SLBxxx.
Temporal Representation: The samples were collected in May 2009.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2002) was followed.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109305, Nickel
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 80335
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to evaluate sediment toxicity. None of the samples exhibited significant toxicity. The toxicity tests included survival and growth of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Santa Lucia Watershed Rotation 2009
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 3 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
Guideline Reference: SWAMP_Memo_Toxicity_Data_Intrepretation
 
Spatial Representation: The samples were collected at station 310SLBxxx.
Temporal Representation: The samples were collected in May 2009.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2002) was followed.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109305, Nickel
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 80334
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to evaluate sediment toxicity. None of the samples exhibited significant toxicity. The toxicity tests included survival and growth of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Coastal Confluences 2008 2009
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 3 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
Guideline Reference: SWAMP_Memo_Toxicity_Data_Intrepretation
 
Spatial Representation: The samples were collected at station 310SLB - San Luis Creek at San Luis Bay Drive.
Temporal Representation: The samples were collected in May 2009.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2002) was followed.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109305, Nickel
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 80337
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to evaluate sediment toxicity. None of the samples exhibited significant toxicity. The toxicity tests included survival and growth of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 3 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
Guideline Reference: SWAMP_Memo_Toxicity_Data_Intrepretation
 
Spatial Representation: The samples were collected at station 310SLBxxx.
Temporal Representation: The samples were collected in June 2008.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2002) was followed.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109305, Nickel
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 170777
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Human health risk associated with organism consumption is 4.6 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109305, Nickel
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 170258
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of inorganic chemicals in excess of the maximum contaminant levels for primary drinking water standards specified in California Code of Regulations, Title 22, Division 4, Chapter 15, Sections 64431 and 64433.2 (Water Quality Control Plan, Central Coast Basin)
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The maximum contaminant level of nickel in public water systems shall be 0.1 mg/L (California Code of Regulations, Title 22, Division 4, Chapter 15, Sections 64431).
Guideline Reference: California MCLs - Title 17 and Title 22 documents for 2019 - California Regulations Related to Drinking Water
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109305, Nickel
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 170676
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan and identified as the maximum concentration for nickel for irrigation supply as 0.2 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109305, Nickel
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 170729
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan and identified as the maximum concentration for nickel for irrigation supply as 0.2 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109305, Nickel
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 170510
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Human health risk associated with organism consumption is 4.6 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109305, Nickel
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 170683
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of inorganic chemicals in excess of the maximum contaminant levels for primary drinking water standards specified in California Code of Regulations, Title 22, Division 4, Chapter 15, Sections 64431 and 64433.2 (Water Quality Control Plan, Central Coast Basin)
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The maximum contaminant level of nickel in public water systems shall be 0.1 mg/L (California Code of Regulations, Title 22, Division 4, Chapter 15, Sections 64431).
Guideline Reference: California MCLs - Title 17 and Title 22 documents for 2019 - California Regulations Related to Drinking Water
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109305, Nickel
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 170837
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Human health risk associated with organism consumption is 4.6 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2013-06-10 and 2017-12-07
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109305, Nickel
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 155048
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 7
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 7 of the 7 samples exceeded the evaluation guideline for Nickel .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for nickel in 48.6 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2018-06-13
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109305, Nickel
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 170556
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of inorganic chemicals in excess of the maximum contaminant levels for primary drinking water standards specified in California Code of Regulations, Title 22, Division 4, Chapter 15, Sections 64431 and 64433.2 (Water Quality Control Plan, Central Coast Basin)
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The maximum contaminant level of nickel in public water systems shall be 0.1 mg/L (California Code of Regulations, Title 22, Division 4, Chapter 15, Sections 64431).
Guideline Reference: California MCLs - Title 17 and Title 22 documents for 2019 - California Regulations Related to Drinking Water
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2013-06-10 and 2017-12-07
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109305, Nickel
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 170658
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109305, Nickel
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 170614
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan and identified as the maximum concentration for nickel for irrigation supply as 0.2 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2013-06-10 and 2017-12-07
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109305, Nickel
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 170775
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2013-06-10 and 2017-12-07
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
130642
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Nitrogen, Nitrite
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the Clean Water Act (CWA) section 303(d) List under section 3.1 of the Listing Policy.

A total of six lines of evidence are available in the administrative record to assess this pollutant. Sample and exceedance counts for the lines of evidence with the fraction identified as “dissolved” are grouped together with those having the fraction “total”, based on the analytical method used. A total of zero of 236 samples exceed the water quality objective for the agricultural supply beneficial use.

After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. A total of zero of 236 samples exceed the water quality objective for the agricultural supply beneficial use. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 130642, Nitrogen, Nitrite
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 52040
 
Pollutant: Nitrogen, Nitrite
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 25
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 25 samples exceed the criterion for Nitrite as N.
Data Reference: Santa Lucia Watershed Rotation field data 2009
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in Table 3-4 (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). Table 3-4 (page III-9) lists the maximum concentration for nitrite for livestock watering is 10 mg/L.
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 2 monitoring sites [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road, 310SLM-San Luis Obispo Creek at Mission Plaza]
Temporal Representation: Data was collected over the time period 1/21/2009-12/16/2009.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 130642, Nitrogen, Nitrite
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 52024
 
Pollutant: Nitrogen, Nitrite
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 40
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 40 samples exceed the criterion for Nitrite as N.
Data Reference: Coastal Confluences field data 2007-2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in Table 3-4 (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). Table 3-4 (page III-9) lists the maximum concentration for nitrite for livestock watering is 10 mg/L.
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 1/18/2007-6/22/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 130642, Nitrogen, Nitrite
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 49219
 
Pollutant: Nitrogen, Nitrite
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 50
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 50 samples exceed the criterion for Nitrite as N.
Data Reference: Nutrient Numeric Endpoint Study for San Luis Obispo Creek, July - August 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in Table 3-4 (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). Table 3-4 (page III-9) lists the maximum concentration for nitrite for livestock watering is 10 mg/L.
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 5 monitoring sites [ Station # 6 West of 101 Bridge, Station # 2 RW4:, Station # 4 RW5, Station # 5 RW 8.2, Station # 7 San Luis Bay Drive at Avila Beach Drive]
Temporal Representation: Data was collected over the time period 7/18/2010-8/16/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: There is no QAPP written specifically for this project. However, The City of SLO's Lab is certified with the Department of Public Health in accordance with the CWC section 13176. In addition QC data are provided with laboratory analyses and QC procedures
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130642, Nitrogen, Nitrite
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 173488
 
Pollutant: Nitrogen, Nitrite
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 12 samples exceeded the water quality threshold for Nitrite as N.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicalslisted in the Central Coast Basin Plan and identified as the maximum concentration for nitrite for livestock watering as 10 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 130642, Nitrogen, Nitrite
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 173306
 
Pollutant: Nitrogen, Nitrite
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 97
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 97 samples exceeded the water quality threshold for Nitrite as N.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicalslisted in the Central Coast Basin Plan and identified as the maximum concentration for nitrite for livestock watering as 10 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-19 and 2018-12-06
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 130642, Nitrogen, Nitrite
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 173491
 
Pollutant: Nitrogen, Nitrite
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 12 samples exceeded the water quality threshold for Nitrite as N.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicalslisted in the Central Coast Basin Plan and identified as the maximum concentration for nitrite for livestock watering as 10 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109307
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Organophosphate Pesticides
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Eight lines of evidence are available in the administrative record to assess this pollutant. Zero of ten water samples exceeded the aquatic life evaluation guideline for additive effects of chlorpyrifos and diazinon (Bailey et al., 1997).

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of ten water samples exceeded the evaluation guideline, and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 109307, Organophosphate Pesticides
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 173519
 
Pollutant: Organophosphate Pesticides
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP SpecialStudies data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Organophosphorus Pesticides.
Data Reference: Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for the protection of aquatic life from the additive effects of the organophophate pesticides chlorpyrifos and diazinon is one toxic unit equivalent. A toxic unit equivalent is equal to the sum of chlorpyrifos and diazinon from a single sample, each having their reported concentration divided their respective evaluation guideline prior to being summed. If this results in a value greater than one, the sample is considered to be in exceedance of the water quality standard. (Bailey et al., 1997).
Guideline Reference: Joint acute toxicity of Diazinon and Chlorpyrifos to Ceriodaphnia dubia.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2018-01-17 and 2018-01-17
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109307, Organophosphate Pesticides
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 173277
 
Pollutant: Organophosphate Pesticides
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP SpecialStudies data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Organophosphorus Pesticides.
Data Reference: Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for the protection of aquatic life from the additive effects of the organophophate pesticides chlorpyrifos and diazinon is one toxic unit equivalent. A toxic unit equivalent is equal to the sum of chlorpyrifos and diazinon from a single sample, each having their reported concentration divided their respective evaluation guideline prior to being summed. If this results in a value greater than one, the sample is considered to be in exceedance of the water quality standard. (Bailey et al., 1997).
Guideline Reference: Joint acute toxicity of Diazinon and Chlorpyrifos to Ceriodaphnia dubia.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2018-01-17 and 2018-01-17
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109307, Organophosphate Pesticides
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 173575
 
Pollutant: Organophosphate Pesticides
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Organophosphorus Pesticides.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for the protection of aquatic life from the additive effects of the organophophate pesticides chlorpyrifos and diazinon is one toxic unit equivalent. A toxic unit equivalent is equal to the sum of chlorpyrifos and diazinon from a single sample, each having their reported concentration divided their respective evaluation guideline prior to being summed. If this results in a value greater than one, the sample is considered to be in exceedance of the water quality standard. (Bailey et al., 1997).
Guideline Reference: Joint acute toxicity of Diazinon and Chlorpyrifos to Ceriodaphnia dubia.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109307, Organophosphate Pesticides
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 173844
 
Pollutant: Organophosphate Pesticides
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Organophosphorus Pesticides.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for the protection of aquatic life from the additive effects of the organophophate pesticides chlorpyrifos and diazinon is one toxic unit equivalent. A toxic unit equivalent is equal to the sum of chlorpyrifos and diazinon from a single sample, each having their reported concentration divided their respective evaluation guideline prior to being summed. If this results in a value greater than one, the sample is considered to be in exceedance of the water quality standard. (Bailey et al., 1997).
Guideline Reference: Joint acute toxicity of Diazinon and Chlorpyrifos to Ceriodaphnia dubia.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109307, Organophosphate Pesticides
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 173533
 
Pollutant: Organophosphate Pesticides
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Organophosphorus Pesticides.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for the protection of aquatic life from the additive effects of the organophophate pesticides chlorpyrifos and diazinon is one toxic unit equivalent. A toxic unit equivalent is equal to the sum of chlorpyrifos and diazinon from a single sample, each having their reported concentration divided their respective evaluation guideline prior to being summed. If this results in a value greater than one, the sample is considered to be in exceedance of the water quality standard. (Bailey et al., 1997).
Guideline Reference: Joint acute toxicity of Diazinon and Chlorpyrifos to Ceriodaphnia dubia.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109307, Organophosphate Pesticides
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 173436
 
Pollutant: Organophosphate Pesticides
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Organophosphorus Pesticides.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for the protection of aquatic life from the additive effects of the organophophate pesticides chlorpyrifos and diazinon is one toxic unit equivalent. A toxic unit equivalent is equal to the sum of chlorpyrifos and diazinon from a single sample, each having their reported concentration divided their respective evaluation guideline prior to being summed. If this results in a value greater than one, the sample is considered to be in exceedance of the water quality standard. (Bailey et al., 1997).
Guideline Reference: Joint acute toxicity of Diazinon and Chlorpyrifos to Ceriodaphnia dubia.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109307, Organophosphate Pesticides
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 173437
 
Pollutant: Organophosphate Pesticides
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Organophosphorus Pesticides.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for the protection of aquatic life from the additive effects of the organophophate pesticides chlorpyrifos and diazinon is one toxic unit equivalent. A toxic unit equivalent is equal to the sum of chlorpyrifos and diazinon from a single sample, each having their reported concentration divided their respective evaluation guideline prior to being summed. If this results in a value greater than one, the sample is considered to be in exceedance of the water quality standard. (Bailey et al., 1997).
Guideline Reference: Joint acute toxicity of Diazinon and Chlorpyrifos to Ceriodaphnia dubia.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109307, Organophosphate Pesticides
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 173687
 
Pollutant: Organophosphate Pesticides
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Organophosphorus Pesticides.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for the protection of aquatic life from the additive effects of the organophophate pesticides chlorpyrifos and diazinon is one toxic unit equivalent. A toxic unit equivalent is equal to the sum of chlorpyrifos and diazinon from a single sample, each having their reported concentration divided their respective evaluation guideline prior to being summed. If this results in a value greater than one, the sample is considered to be in exceedance of the water quality standard. (Bailey et al., 1997).
Guideline Reference: Joint acute toxicity of Diazinon and Chlorpyrifos to Ceriodaphnia dubia.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
130684
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: PAHs (Polycyclic Aromatic Hydrocarbons)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) List under section 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment. The pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the 303(d) List.

Two lines of evidence are available in the administrative record to assess this pollutant.

Two LOEs summarize sediment samples. Zero of two sediment samples exceed the total PAHs evaluation guideline (MacDonald et al., 2000a) set to protect for the aquatic life beneficial use.

After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. No sediment samples exceeded the evaluation guidelines set to protect aquatic life beneficial uses and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 130684, PAHs (Polycyclic Aromatic Hydrocarbons)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 155132
 
Pollutant: PAHs (Polycyclic Aromatic Hydrocarbons)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for PAHs (Polycyclic Aromatic Hydrocarbons) .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Total PAHs from MacDonald et al., 2000a which states that the probable effect concentration for Total PAHs is 22800 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 130684, PAHs (Polycyclic Aromatic Hydrocarbons)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 155153
 
Pollutant: PAHs (Polycyclic Aromatic Hydrocarbons)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for PAHs (Polycyclic Aromatic Hydrocarbons) .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Total PAHs from MacDonald et al., 2000a which states that the probable effect concentration for Total PAHs is 22800 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109311
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: PCBs (Polychlorinated biphenyls)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) List under section 3.1 and section 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment. The pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the 303(d) List.

Three lines of evidence are available in the administrative record to assess this pollutant.

Zero of six sediment samples exceed the PCBs evaluation guideline for Cold Freshwater Habitat beneficial use. Zero of seven sediment samples exceed the PCBs evaluation guideline for Warm Freshwater Habitat beneficial use.

After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. None sediment samples exceed the evaluation guidelines and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109311, PCBs (Polychlorinated biphenyls)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57903
 
Pollutant: PCBs (Polychlorinated biphenyls)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Zero of 1 sample collected for Total PCBs exceeded the evaluation guideline.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain settleable material in concentrations that result in deposition of material that causes nuisance or adversely affects beneficial uses (Water Quality Control Plan for the Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for total PCB is 676 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data were collected at the following station 310SLBxxx (310SLB-San Luis Obispo Creek at San Luis Bay Drive).
Temporal Representation: The samples were collected on 6/11/2008.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109311, PCBs (Polychlorinated biphenyls)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 154954
 
Pollutant: PCBs (Polychlorinated biphenyls)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for PCBs (Polychlorinated biphenyls) .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for PCBs in 676 ug/Kg dry weight (MacDonald et al. 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2017-06-05
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109311, PCBs (Polychlorinated biphenyls)
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 155098
 
Pollutant: PCBs (Polychlorinated biphenyls)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for PCBs (Polychlorinated biphenyls) .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for sum of PCB Arochlors is 676 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2017-06-05
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109346
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Permethrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 at least one line of evidence is necessary to assess listing status, but under section 3.6 at least two lines of evidence are necessary to assess listing status and the pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the section 303(d) List.

Twelve lines of evidence are available in the administrative record to assess this pollutant. Zero of six sediment samples exceed the evaluation guideline and zero of zero water samples exceed the evaluation guideline used to interpret the narrative water quality objective for aquatic life protection. Note, the water sample results were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy. This sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported using table 3.1. Therefore, the use support rating is set to 'insufficient information'.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the samples exceed the evaluation guidelines and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 109346, Permethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57910
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Permethrin, total.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for permethrin is the median lethal concentration (LC50) of 8.9 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 8.9 ug/g is the geometric mean of LC50 values for permethrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109346, Permethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57904
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Permethrin, total.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for permethrin is the median lethal concentration (LC50) of 8.9 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 8.9 ug/g is the geometric mean of LC50 values for permethrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109346, Permethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 176967
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Permethrin. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of permethrin does not exceed 0.002 ug/L (2 ng/L) more than once every three years on the average (Fojut et al., 2012).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV).
Temporal Representation: Date for this waterbody was collected over the date range 2015-05-20 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109346, Permethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 176945
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Permethrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of permethrin does not exceed 0.002 ug/L (2 ng/L) more than once every three years on the average (Fojut et al., 2012).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Date for this waterbody was collected over the date range 2015-09-09 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109346, Permethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 177013
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Permethrin. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of permethrin does not exceed 0.002 ug/L (2 ng/L) more than once every three years on the average (Fojut et al., 2012).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV).
Temporal Representation: Date for this waterbody was collected over the date range 2015-05-20 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109346, Permethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 148447
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends Project (SPoT) data for San Luis Obispo Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Permethrin, Total.
Data Reference: SPoT sediment data: 6/5/2018--6/13/2018.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for permethrin is the median lethal concentration (LC50) of 8.9 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 8.9 ug/g is the geometric mean of LC50 values for permethrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB
Temporal Representation: Data for this waterbody were collected on 06/13/2018.
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAPP and the SWAMP-SPoT QAPP. QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109346, Permethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 177041
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Permethrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of permethrin does not exceed 0.002 ug/L (2 ng/L) more than once every three years on the average (Fojut et al., 2012).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Date for this waterbody was collected over the date range 2015-09-09 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109346, Permethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 177061
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Permethrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of permethrin does not exceed 0.002 ug/L (2 ng/L) more than once every three years on the average (Fojut et al., 2012).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM).
Temporal Representation: Date for this waterbody was collected over the date range 2015-09-09 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109346, Permethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 148448
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends Project (SPoT) data for San Luis Obispo Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Permethrin, Total.
Data Reference: SPoT sediment data: 6/5/2018--6/13/2018.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for permethrin is the median lethal concentration (LC50) of 8.9 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 8.9 ug/g is the geometric mean of LC50 values for permethrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB
Temporal Representation: Data for this waterbody were collected on 06/13/2018.
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAPP and the SWAMP-SPoT QAPP. QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109346, Permethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 154915
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Permethrin, Total .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for permethrin is the median lethal concentration (LC50) of 8.9 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 8.9 ug/g is the geometric mean of LC50 values for permethrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2011-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109346, Permethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 176968
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Permethrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of permethrin does not exceed 0.002 ug/L (2 ng/L) more than once every three years on the average (Fojut et al., 2012).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM).
Temporal Representation: Date for this waterbody was collected over the date range 2015-09-09 to 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109346, Permethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 155369
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Permethrin, Total .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for permethrin is the median lethal concentration (LC50) of 8.9 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 8.9 ug/g is the geometric mean of LC50 values for permethrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2011-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109310
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Phenanthrene
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) list under section 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment. The pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the Section 303(d) list.

Six lines of evidence (LOEs) are available in the administrative record to assess this pollutant.
Sample and exceedance counts for the lines of evidence with the fraction identified as “none” or “not recorded” are grouped together with those having the fraction “total”, based on the analytical method used. The following is a summary of the sample and exceedances for each beneficial use:

Zero of four sediment samples exceed the aquatic life evaluation guideline. This sample size is insufficient to determine an applicable beneficial use support rating with the power and confidence of the Listing Policy. In accordance with Table 3.1 of the Listing Policy, a minimum of 16 samples is needed to determine if a beneficial use is fully supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:

1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero samples exceed the evaluation guideline and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109310, Phenanthrene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 155242
 
Pollutant: Phenanthrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Phenanthrene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for phenanthrene is 1,170 ug/kg dry weight (MacDonald et al 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109310, Phenanthrene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 16971
 
Pollutant: Phenanthrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Phenanthrene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for Phenanthrene is 1170 ug/Kg dry weight (Macdonald et al. 2000)
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109310, Phenanthrene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 17039
 
Pollutant: Phenanthrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Phenanthrene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for Phenanthrene is 1170 ug/Kg dry weight (Macdonald et al. 2000)
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109310, Phenanthrene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 16972
 
Pollutant: Phenanthrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Phenanthrene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for Phenanthrene is 1170 ug/Kg dry weight (Macdonald et al. 2000)
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109310, Phenanthrene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 17040
 
Pollutant: Phenanthrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Phenanthrene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for Phenanthrene is 1170 ug/Kg dry weight (Macdonald et al. 2000)
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109310, Phenanthrene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 155302
 
Pollutant: Phenanthrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Phenanthrene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for phenanthrene is 1,170 ug/kg dry weight (MacDonald et al 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109329
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Phorate
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Six lines of evidence are available in the administrative record to assess this pollutant. Zero of three water samples exceeded the USEPA aquatic life evaluation guideline. Zero of three water samples exceed the National Academy of Sciences drinking water health advisory for municipal and domestic water supply. These sample sizes are insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is supported using table 3.1.

After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List because applicable water quality standards are not being exceeded.

This conclusion is based on the staff findings that:

1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.

2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.

3. Zero samples exceed the evaluation guidelines. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.

4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 109329, Phorate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 180324
 
Pollutant: Phorate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Phorate.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Phorate is the USEPA Aquatic Life Benchmark of 0.21 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2013-06-19
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109329, Phorate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 180270
 
Pollutant: Phorate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP SpecialStudies data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Phorate.
Data Reference: Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The National Academy of Sciences health advisory for phorate is 0.7 ug/L. This was calculated using the no-adverse-effect dosage of 0.01 mg/kg, assuming 70 kg body weight, 2 liters/day water consumption, 20% relative source contribution from drinking water, and divided by 100 for a factor of safety.
Guideline Reference: National Academy of Sciences - Volume I Drinking Water and Health
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2018-01-17 and 2018-01-17
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109329, Phorate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 180246
 
Pollutant: Phorate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Phorate.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The National Academy of Sciences health advisory for phorate is 0.7 ug/L. This was calculated using the no-adverse-effect dosage of 0.01 mg/kg, assuming 70 kg body weight, 2 liters/day water consumption, 20% relative source contribution from drinking water, and divided by 100 for a factor of safety.
Guideline Reference: National Academy of Sciences - Volume I Drinking Water and Health
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2013-06-19
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109329, Phorate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 180131
 
Pollutant: Phorate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP SpecialStudies data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Phorate.
Data Reference: Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Phorate is the USEPA Aquatic Life Benchmark of 0.21 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2018-01-17 and 2018-01-17
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109329, Phorate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 180351
 
Pollutant: Phorate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP SpecialStudies data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Phorate.
Data Reference: Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Phorate is the USEPA Aquatic Life Benchmark of 0.21 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2018-01-17 and 2018-01-17
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109329, Phorate
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 180228
 
Pollutant: Phorate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Phorate.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Phorate is the USEPA Aquatic Life Benchmark of 0.21 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2013-06-19
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109334
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Phosmet
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Six lines of evidence are available in the administrative record to assess this pollutant. Zero of three water samples exceed the USEPA aquatic life evaluation guideline. Zero of three samples exceed the USEPA drinking water health advisory. These sample sizes are insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is supported using table 3.1.

After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List because applicable water quality standards are not being exceeded.

This conclusion is based on the staff findings that:

1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.

2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.

3. Zero samples exceed the evaluation guidelines. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.

4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 109334, Phosmet
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 180586
 
Pollutant: Phosmet
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Phosmet.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Phosmet is the USEPA Aquatic Life Benchmark of 0.8 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2013-06-19
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109334, Phosmet
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 180336
 
Pollutant: Phosmet
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP SpecialStudies data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Phosmet.
Data Reference: Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Based on USEPA IRIS reference dose (RfD) as a drinking water level, the drinking water health advisory level for phosmet is 140 ug/L. This was calculated assuming 70 kg body weight, 2 liters/day water consumption, and 20% relative source contribution from drinking water. An additional uncertainty factor of 10 is used for Class C carcinogens.
Guideline Reference: IRIS Reference Summary (Various Pollutants)
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2018-01-17 and 2018-01-17
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109334, Phosmet
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 180252
 
Pollutant: Phosmet
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Phosmet.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Phosmet is the USEPA Aquatic Life Benchmark of 0.8 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2013-06-19
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109334, Phosmet
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 180636
 
Pollutant: Phosmet
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP SpecialStudies data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Phosmet.
Data Reference: Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Phosmet is the USEPA Aquatic Life Benchmark of 0.8 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2018-01-17 and 2018-01-17
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109334, Phosmet
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 180503
 
Pollutant: Phosmet
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Phosmet.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Based on USEPA IRIS reference dose (RfD) as a drinking water level, the drinking water health advisory level for phosmet is 140 ug/L. This was calculated assuming 70 kg body weight, 2 liters/day water consumption, and 20% relative source contribution from drinking water. An additional uncertainty factor of 10 is used for Class C carcinogens.
Guideline Reference: IRIS Reference Summary (Various Pollutants)
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2013-06-19
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109334, Phosmet
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 180377
 
Pollutant: Phosmet
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP SpecialStudies data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Phosmet.
Data Reference: Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Phosmet is the USEPA Aquatic Life Benchmark of 0.8 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2018-01-17 and 2018-01-17
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109344
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Propiconazole
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the Clean Water Act (CWA) section 303(d) List under section 3.1 of the Listing Policy.

A total of nine lines of evidence are available in the administrative record to assess this pollutant. A total of zero of six samples exceed the evaluation guideline for the cold freshwater habitat beneficial use, zero of six samples exceed the evaluation guideline for the municipal and domestic supply beneficial use and zero of six samples exceed the evaluation guideline for the warm freshwater habitat beneficial use. These data are insufficient to determine the applicable beneficial use support rating with the power and confidence required by the Listing Policy.

After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. A total of zero of six samples exceed the evaluation guideline for the cold freshwater habitat beneficial use, zero of six samples exceed the evaluation guideline for the municipal and domestic supply beneficial use and zero of six samples exceed the evaluation guideline for the warm freshwater habitat beneficial use. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 109344, Propiconazole
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 180690
 
Pollutant: Propiconazole
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Propiconazole.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The USEPA expected safe lifetime exposure limit in drinking water for Propiconazole, calculated using the IRIS Reference Dose, is 91 ug/L. This was calculated assuming 70 kg body weight, 2 liters/day water consumption, 20% relative source contribution from drinking water, and 0.013 mg/kg/day as the reference dose.
Guideline Reference: IRIS Reference Summary (Various Pollutants)
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109344, Propiconazole
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 180711
 
Pollutant: Propiconazole
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Propiconazole.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Propiconazole is the USEPA Aquatic Life Benchmark of 21 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109344, Propiconazole
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 180732
 
Pollutant: Propiconazole
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Propiconazole.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Propiconazole is the USEPA Aquatic Life Benchmark of 21 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109344, Propiconazole
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 180652
 
Pollutant: Propiconazole
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Propiconazole.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The USEPA expected safe lifetime exposure limit in drinking water for Propiconazole, calculated using the IRIS Reference Dose, is 91 ug/L. This was calculated assuming 70 kg body weight, 2 liters/day water consumption, 20% relative source contribution from drinking water, and 0.013 mg/kg/day as the reference dose.
Guideline Reference: IRIS Reference Summary (Various Pollutants)
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109344, Propiconazole
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 180734
 
Pollutant: Propiconazole
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Propiconazole.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Propiconazole is the USEPA Aquatic Life Benchmark of 21 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109344, Propiconazole
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 180730
 
Pollutant: Propiconazole
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Propiconazole.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Propiconazole is the USEPA Aquatic Life Benchmark of 21 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109344, Propiconazole
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 180607
 
Pollutant: Propiconazole
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Propiconazole.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Propiconazole is the USEPA Aquatic Life Benchmark of 21 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109344, Propiconazole
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 180564
 
Pollutant: Propiconazole
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Propiconazole.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Propiconazole is the USEPA Aquatic Life Benchmark of 21 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109344, Propiconazole
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 180651
 
Pollutant: Propiconazole
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Propiconazole.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The USEPA expected safe lifetime exposure limit in drinking water for Propiconazole, calculated using the IRIS Reference Dose, is 91 ug/L. This was calculated assuming 70 kg body weight, 2 liters/day water consumption, 20% relative source contribution from drinking water, and 0.013 mg/kg/day as the reference dose.
Guideline Reference: IRIS Reference Summary (Various Pollutants)
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109347
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Pyraclostrobin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 109347, Pyraclostrobin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 180824
 
Pollutant: Pyraclostrobin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Pyraclostrobin.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Pyraclostrobin is the USEPA Aquatic Life Benchmark of 1.5 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109347, Pyraclostrobin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 180476
 
Pollutant: Pyraclostrobin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Pyraclostrobin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Pyraclostrobin is the USEPA Aquatic Life Benchmark of 1.5 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109347, Pyraclostrobin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 180495
 
Pollutant: Pyraclostrobin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Pyraclostrobin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Pyraclostrobin is the USEPA Aquatic Life Benchmark of 1.5 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109347, Pyraclostrobin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 180471
 
Pollutant: Pyraclostrobin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Pyraclostrobin.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Pyraclostrobin is the USEPA Aquatic Life Benchmark of 1.5 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109347, Pyraclostrobin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 180825
 
Pollutant: Pyraclostrobin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Pyraclostrobin.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Pyraclostrobin is the USEPA Aquatic Life Benchmark of 1.5 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109347, Pyraclostrobin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 180519
 
Pollutant: Pyraclostrobin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Pyraclostrobin.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Pyraclostrobin is the USEPA Aquatic Life Benchmark of 1.5 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109312
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Pyrene
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) list under section 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment. The pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the Section 303(d) list.

Six lines of evidence (LOEs) are available in the administrative record to assess this pollutant.
Sample and exceedance counts for the lines of evidence with the fraction identified as “none” or “not recorded” are grouped together with those having the fraction “total”, based on the analytical method used. The following is a summary of the sample and exceedances for each beneficial use:

Zero of four sediment samples exceed the aquatic life evaluation guideline. This sample size is insufficient to determine an applicable beneficial use support rating with the power and confidence of the Listing Policy. In accordance with Table 3.1 of the Listing Policy, a minimum of 16 samples is needed to determine if a beneficial use is fully supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:

1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero samples exceed the evaluation guideline and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109312, Pyrene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 155456
 
Pollutant: Pyrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Pyrene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for pyrene is 1,520 ug/kg dry weight (MacDonald et al 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109312, Pyrene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 155400
 
Pollutant: Pyrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Pyrene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for pyrene is 1,520 ug/kg dry weight (MacDonald et al 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2015-05-27
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109312, Pyrene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 17102
 
Pollutant: Pyrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Pyrene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for Pyrene is 1520 ug/Kg dry weight (Macdonald et al. 2000)
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109312, Pyrene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 17948
 
Pollutant: Pyrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Pyrene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for Pyrene is 1520 ug/Kg dry weight (Macdonald et al. 2000)
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109312, Pyrene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 17089
 
Pollutant: Pyrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Pyrene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for Pyrene is 1520 ug/Kg dry weight (Macdonald et al. 2000)
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109312, Pyrene
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 17934
 
Pollutant: Pyrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Pyrene.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for Pyrene is 1520 ug/Kg dry weight (Macdonald et al. 2000)
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
 
DECISION ID
109320
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Pyrethroids
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment. The pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the Section 303(d) List.

Two lines of evidence are available in the administrative record to assess this pollutant.

Zero of the seven sediment samples exceed the evaluation guideline applied to protect for aquatic life beneficial uses.
A minimum of 16 samples is needed to determine if a beneficial use is supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported using table 3.1 of the Listing Policy. Therefore, the use support rating is set to 'insufficient information'.
After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the seven sediment samples exceed the evaluation guideline applied to protect for aquatic life beneficial uses and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 109320, Pyrethroids
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 155544
 
Pollutant: Pyrethroids
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 7 samples exceeded the evaluation guideline for Pyrethroids .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for the protection of aquatic life from pyrethroids is one toxic unit equivalent. A toxic unit equivalent is equal to the sum of; Bifenthrin, Cyfluthrin, Cypermethrin, Lambda-Cyhalothrin, and Permethrin, each having their reported concentration divided their respective evaluation guideline prior to being summed. If this results in a value greater than one, the sample day is considered to be in exceedance of the water quality standard. (Department of Fish and Game Aquatic Life Criteria for Pyrethroid Insecticides, 2000)
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2017-06-05
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109320, Pyrethroids
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 155617
 
Pollutant: Pyrethroids
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 7 samples exceeded the evaluation guideline for Pyrethroids .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for the protection of aquatic life from pyrethroids is one toxic unit equivalent. A toxic unit equivalent is equal to the sum of; Bifenthrin, Cyfluthrin, Cypermethrin, Lambda-Cyhalothrin, and Permethrin, each having their reported concentration divided their respective evaluation guideline prior to being summed. If this results in a value greater than one, the sample day is considered to be in exceedance of the water quality standard. (Department of Fish and Game Aquatic Life Criteria for Pyrethroid Insecticides, 2000)
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2017-06-05
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109313
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Selenium
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 109313, Selenium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 181481
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan and identified as the maximum concentration for selenium for irrigation supply as 0.02 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109313, Selenium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 180763
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The criterion continuous concentration to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2013-06-10 and 2017-12-07
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109313, Selenium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 181238
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All inland surface waters, enclosed bays, and estuaries shall not contain concentrations of inorganic chemicals in excess of the maximum contaminant levels for primary drinking water standards specified in California Code of Regulations, Title 22, Division 4, Chapter 15, Sections 64431 and 64433.2.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The California Maximum Contaminant Level for selenium is 0.05 mg/L (California Code of Regulations, Title 22).
Guideline Reference: California MCLs - Title 17 and Title 22 documents for 2019 - California Regulations Related to Drinking Water
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2013-06-10 and 2017-12-07
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109313, Selenium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 181011
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan and identified as the maximum concentration for selenium for irrigation supply as 0.02 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2013-06-10 and 2017-12-07
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109313, Selenium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 181527
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The criterion continuous concentration to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109313, Selenium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 181087
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The criterion continuous concentration to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109313, Selenium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 181186
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The criterion continuous concentration to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109313, Selenium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 181267
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan and identified as the maximum concentration for selenium for irrigation supply as 0.02 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109313, Selenium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 181189
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The criterion continuous concentration to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109313, Selenium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 181525
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All inland surface waters, enclosed bays, and estuaries shall not contain concentrations of inorganic chemicals in excess of the maximum contaminant levels for primary drinking water standards specified in California Code of Regulations, Title 22, Division 4, Chapter 15, Sections 64431 and 64433.2.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The California Maximum Contaminant Level for selenium is 0.05 mg/L (California Code of Regulations, Title 22).
Guideline Reference: California MCLs - Title 17 and Title 22 documents for 2019 - California Regulations Related to Drinking Water
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109313, Selenium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 181363
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All inland surface waters, enclosed bays, and estuaries shall not contain concentrations of inorganic chemicals in excess of the maximum contaminant levels for primary drinking water standards specified in California Code of Regulations, Title 22, Division 4, Chapter 15, Sections 64431 and 64433.2.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The California Maximum Contaminant Level for selenium is 0.05 mg/L (California Code of Regulations, Title 22).
Guideline Reference: California MCLs - Title 17 and Title 22 documents for 2019 - California Regulations Related to Drinking Water
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109313, Selenium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 181432
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The criterion continuous concentration to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2013-06-10 and 2017-12-07
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109314
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Silver
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 109314, Silver
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 181716
 
Pollutant: Silver
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Silver.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion maximum concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109314, Silver
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 181358
 
Pollutant: Silver
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Silver.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion maximum concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2013-06-10 and 2017-12-07
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109314, Silver
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 181782
 
Pollutant: Silver
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Silver.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion maximum concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109314, Silver
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 181929
 
Pollutant: Silver
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Silver.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion maximum concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2013-06-10 and 2017-12-07
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109314, Silver
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 181741
 
Pollutant: Silver
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Silver.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion maximum concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109314, Silver
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 181830
 
Pollutant: Silver
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Silver.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion maximum concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
126402
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Specific Conductivity
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the Clean Water Act (CWA) section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

A total of 10 lines of evidence are available in the administrative record to assess this pollutant. Sample and exceedance counts for the lines of evidence with the fraction identified as “none” or “not recorded” are grouped together with those having the fraction “total”, based on the analytical method used. Once summed, a total of zero of 283 samples exceed the water quality objective for agricultural supply. Note that the pollutant name for the older LOEs is electrical conductivity. This was an error and the pollutant name should have always been specific conductivity. For this reason, all 10 of the LOEs are combined into this assessment for specific conductivity.

After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. A total of zero of 283 samples exceed the water quality objective for agricultural supply and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 126402, Specific Conductivity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 182420
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 13
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 13 samples exceeded the water quality threshold for SpecificConductivity.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines listed in the Central Coast Basin Plan and identified as the level at which severe problems may occur when EC exceeds 3.0 mmho/cm in irrigation supply water (meaurements reported at 25 degrees C). EC measured, at 25 degrees C , is referred to as specific conductivity. Also note that 1 mmho/cm = 1000 uS/cm.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 126402, Specific Conductivity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 11828
 
Pollutant: Electrical Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Diurnal Dissolved Oxygen Sampling (DO) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 7 samples exceed the criterion for Conductivity(Us).
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines provided in Table 3-3 (Central Coast Waterboard Basin Plan, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). In Table 3-3 of the Basin Plan (page III-8), water quality guidelines state that severe problems may occur when conductivity exceeds 3.0 mS/cm in irrigation supply water.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 7/3/2001-8/7/2006. Diurnal monitoring conducted in summer months at all CCAMP monitoring sites.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 126402, Specific Conductivity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 11792
 
Pollutant: Electrical Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 59
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Coastal Confluences (CC) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 59 samples exceed the criterion for Conductivity(Us).
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines provided in Table 3-3 (Central Coast Waterboard Basin Plan, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). In Table 3-3 of the Basin Plan (page III-8), water quality guidelines state that severe problems may occur when conductivity exceeds 3.0 mS/cm in irrigation supply water.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 4/24/2001-12/20/2006. CCAMP Coastal confluence monitoring is conducted monthly (with the exception of April 2003 - December 2003) and is ongoing.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 126402, Specific Conductivity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 11608
 
Pollutant: Electrical Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Santa Lucia (SantaLucia) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 16 samples exceed the criterion for Conductivity(Us).
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines provided in Table 3-3 (Central Coast Waterboard Basin Plan, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). In Table 3-3 of the Basin Plan (page III-8), water quality guidelines state that severe problems may occur when conductivity exceeds 3.0 mS/cm in irrigation supply water.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/15/2002-3/19/2003. Santa Lucia Coast is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 126402, Specific Conductivity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 182620
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for SpecificConductivity.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines listed in the Central Coast Basin Plan and identified as the level at which severe problems may occur when EC exceeds 3.0 mmho/cm in irrigation supply water (meaurements reported at 25 degrees C). EC measured, at 25 degrees C , is referred to as specific conductivity. Also note that 1 mmho/cm = 1000 uS/cm.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2016-07-13
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 126402, Specific Conductivity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 52003
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 42
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 42 samples exceed the criterion for Conductivity(Us).
Data Reference: Coastal Confluences field data 2007-2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines provided in Table 3-3 (Central Coast Waterboard Basin Plan, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). In Table 3-3 of the Basin Plan (page III-8), water quality guidelines state that severe problems may occur when conductivity exceeds 3000 uS/cm in irrigation supply water.
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 1/18/2007-6/22/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 126402, Specific Conductivity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 182678
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 100
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 100 samples exceeded the water quality threshold for SpecificConductivity.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines listed in the Central Coast Basin Plan and identified as the level at which severe problems may occur when EC exceeds 3.0 mmho/cm in irrigation supply water (meaurements reported at 25 degrees C). EC measured, at 25 degrees C , is referred to as specific conductivity. Also note that 1 mmho/cm = 1000 uS/cm.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2019-03-06
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 126402, Specific Conductivity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 182537
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Dissolved Oxygen Study data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for SpecificConductivity.
Data Reference: Field data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines listed in the Central Coast Basin Plan and identified as the level at which severe problems may occur when EC exceeds 3.0 mmho/cm in irrigation supply water (meaurements reported at 25 degrees C). EC measured, at 25 degrees C , is referred to as specific conductivity. Also note that 1 mmho/cm = 1000 uS/cm.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2012-07-16 and 2012-07-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 126402, Specific Conductivity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 182626
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for SpecificConductivity.
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines listed in the Central Coast Basin Plan and identified as the level at which severe problems may occur when EC exceeds 3.0 mmho/cm in irrigation supply water (meaurements reported at 25 degrees C). EC measured, at 25 degrees C , is referred to as specific conductivity. Also note that 1 mmho/cm = 1000 uS/cm.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2013-05-30 and 2018-06-13
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 126402, Specific Conductivity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 52004
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 25
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 25 samples exceed the criterion for Conductivity(Us).
Data Reference: Santa Lucia Watershed Rotation field data 2009
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines provided in Table 3-3 (Central Coast Waterboard Basin Plan, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). In Table 3-3 of the Basin Plan (page III-8), water quality guidelines state that severe problems may occur when conductivity exceeds 3000 uS/cm in irrigation supply water.
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 2 monitoring sites [ 310SLM-San Luis Obispo Creek at Mission Plaza, 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/21/2009-12/16/2009.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
 
DECISION ID
126162
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Temperature, water
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the Clean Water Act (CWA) section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

A total of 10 lines of evidence are available in the administrative record to assess this pollutant. A total of zero of 291 samples exceed the evaluation guideline (Moyle 1976) applied to protect the cold freshwater habitat beneficial use.

After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. A total of zero of 291 samples exceed the evaluation guideline applied to protect the cold freshwater habitat beneficial use and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 126162, Temperature, water
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 12502
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 13
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Diurnal Dissolved Oxygen Sampling (DO) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 13 samples exceed the criterion for Water Temperature.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses (General Objective in Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).
Guideline Reference: Inland Fishes of California
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 2 monitoring sites [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive, 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 7/3/2001-8/7/2006. Diurnal monitoring conducted in summer months at all CCAMP monitoring sites.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 126162, Temperature, water
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 12558
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Santa Lucia (SantaLucia) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 16 samples exceed the criterion for Water Temperature.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses (General Objective in Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).
Guideline Reference: Inland Fishes of California
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/15/2002-3/19/2003. Santa Lucia Coast is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 126162, Temperature, water
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51948
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 25
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 25 samples exceed the criterion for Water Temperature.
Data Reference: Santa Lucia Watershed Rotation field data 2009
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline: The optimum range for growth and completion of most life stages of rainbow trout is 13-21 degrees Celsius (Moyle 1976).
Guideline Reference: Inland Fishes of California
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 2 monitoring sites [ 310SLM-San Luis Obispo Creek at Mission Plaza, 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/21/2009-12/16/2009.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 126162, Temperature, water
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51934
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 41
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 41 samples exceed the criterion for Water Temperature.
Data Reference: Coastal Confluences field data 2007-2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline: The optimum range for growth and completion of most life stages of rainbow trout is 13-21 degrees Celsius (Moyle 1976).
Guideline Reference: Inland Fishes of California
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 1/18/2007-6/22/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 126162, Temperature, water
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 12736
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 59
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Coastal Confluences (CC) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 59 samples exceed the criterion for Water Temperature.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses (General Objective in Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).
Guideline Reference: Inland Fishes of California
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 4/24/2001-12/20/2006. CCAMP Coastal confluence monitoring is conducted monthly (with the exception of April 2003 - December 2003) and is ongoing.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 126162, Temperature, water
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 217108
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The optimum range for growth and completion of most life stages of rainbow trout is 13-21 degrees Celsius (Moyle 1976).
Guideline Reference: Inland Fishes of California
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2016-07-13
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 126162, Temperature, water
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 217121
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 13
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 13 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The optimum range for growth and completion of most life stages of rainbow trout is 13-21 degrees Celsius (Moyle 1976).
Guideline Reference: Inland Fishes of California
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 126162, Temperature, water
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 217102
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 103
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 103 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The optimum range for growth and completion of most life stages of rainbow trout is 13-21 degrees Celsius (Moyle 1976).
Guideline Reference: Inland Fishes of California
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2019-03-06
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 126162, Temperature, water
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 217061
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The optimum range for growth and completion of most life stages of rainbow trout is 13-21 degrees Celsius (Moyle 1976).
Guideline Reference: Inland Fishes of California
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2013-05-30 and 2018-06-13
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 126162, Temperature, water
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 217016
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Dissolved Oxygen Study data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Temperature.
Data Reference: Field data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The optimum range for growth and completion of most life stages of rainbow trout is 13-21 degrees Celsius (Moyle 1976).
Guideline Reference: Inland Fishes of California
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2012-07-16 and 2012-07-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109315
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Terbufos
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 109315, Terbufos
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 156538
 
Pollutant: Terbufos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Terbufos. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Terbufos is the USEPA Aquatic Life Benchmark of 0.03 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Date for this waterbody was collected over the date range 2010-07-21 to 2013-06-19
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109315, Terbufos
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 156519
 
Pollutant: Terbufos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Terbufos. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Terbufos is the USEPA Aquatic Life Benchmark of 0.03 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Date for this waterbody was collected over the date range 2010-07-21 to 2013-06-19
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109315, Terbufos
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 156537
 
Pollutant: Terbufos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Terbufos.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The USEPA drinking water health advisory for terbufos is 0.4 ug/L.
Guideline Reference: 2018 Edition of the Drinking Water Standards and Health Advisories
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2013-06-19
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109317
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Trichlorfon
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 109317, Trichlorfon
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 183323
 
Pollutant: Trichlorfon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Trichlorfon.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The acceptable daily intake for Trichlorfon is 26 ug/l. This was calculated for a child assuming 10 kg body weight, 1 liter/day water consumption, 20% relative source contribution from drinking water, and 1.25 mg/kg/day as the reference dose. (National Academy of Sciences Drinking Water and Health, Volume 6, 1986)
Guideline Reference: National Academy of Sciences Health Advisories document 1986
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2010-07-21
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109317, Trichlorfon
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 183362
 
Pollutant: Trichlorfon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Trichlorfon. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Trichlorofon is the USEPA Aquatic Life Benchmark of 0.0057 ug/L for an invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Date for this waterbody was collected over the date range 2010-07-21 to 2010-07-21
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109317, Trichlorfon
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 183300
 
Pollutant: Trichlorfon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Trichlorfon. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Trichlorofon is the USEPA Aquatic Life Benchmark of 0.0057 ug/L for an invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB).
Temporal Representation: Date for this waterbody was collected over the date range 2010-07-21 to 2010-07-21
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109318
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Turbidity
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the Clean Water Act (CWA) section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

A total of 16 lines of evidence are available in the administrative record to assess this pollutant. Sample and exceedance counts for the lines of evidence with the fraction identified as “none” or “not recorded” are grouped together with those having the fraction “total”, based on the analytical method used. Once summed, a total of 14 of 261 samples exceed the evaluation guideline for cold freshwater habitat (Sigler et al. 1984) and 10 of 261 samples exceed the evaluation guideline for warm freshwater habitat (Shoup, D.E. and Wahl D.H., 2009) used to interpret the water quality objectives for the aquatic life beneficial uses.

After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. A total of 14 of 261 samples exceed the evaluation guideline for cold freshwater habitat and 10 of 261 samples exceed the evaluation guideline for warm freshwater habitat and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109318, Turbidity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 12556
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Santa Lucia (SantaLucia) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 1 of 16 samples exceed the criterion for Turbidity(NTU).
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses. Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Sigler et al. (1984) states that turbidities of 25 NTU's or greater caused reduction in juvenile salmonid growth due to interference with their ability to find food.
Guideline Reference: Effects of chronic turbidity on density and growth of steelheads and coho salmon. Transactions of the American Fisheries Society 113:142-150
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/15/2002-3/19/2003. Santa Lucia Coast is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109318, Turbidity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51933
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 25
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 1 of 25 samples exceed the criterion for Turbidity(NTU).
Data Reference: Santa Lucia Watershed Rotation field data 2009
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses. (Basin Plan)
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline: Turbidities of 25 NTU or greater can cause a reduction in juvenile salmonid growth due to interference with their ability to find food (Sigler et al. 1984).
Guideline Reference: Effects of chronic turbidity on density and growth of steelheads and coho salmon. Transactions of the American Fisheries Society 113:142-150
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 2 monitoring sites [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road, 310SLM-San Luis Obispo Creek at Mission Plaza]
Temporal Representation: Data was collected over the time period 1/21/2009-12/16/2009.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109318, Turbidity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51918
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 39
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 2 of 39 samples exceed the criterion for Turbidity(NTU).
Data Reference: Coastal Confluences field data 2007-2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline: Turbidities of 40 NTU or greater can cause a reduction in piscivorous fish (largemouth bass) growth due to interference with their ability to find food (Shoup, D.E. and Wahl D.H., 2009).
Guideline Reference: The Effects of Turbidity on Prey Selection by Piscivorous Largemouth Bass
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 1/18/2007-6/22/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109318, Turbidity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 12487
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Diurnal Dissolved Oxygen Sampling (DO) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceed the criterion for Turbidity(NTU).
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses. Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Sigler et al. (1984) states that turbidities of 25 NTU's or greater caused reduction in juvenile salmonid growth due to interference with their ability to find food.
Guideline Reference: Effects of chronic turbidity on density and growth of steelheads and coho salmon. Transactions of the American Fisheries Society 113:142-150
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 7/3/2001-8/30/2001. Diurnal monitoring conducted in summer months at all CCAMP monitoring sites.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109318, Turbidity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 12557
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Santa Lucia (SantaLucia) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 1 of 16 samples exceed the criterion for Turbidity(NTU).
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses. Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Sigler et al. (1984) states that turbidities of 25 NTU's or greater caused reduction in juvenile salmonid growth due to interference with their ability to find food.
Guideline Reference: Effects of chronic turbidity on density and growth of steelheads and coho salmon. Transactions of the American Fisheries Society 113:142-150
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/15/2002-3/19/2003. Santa Lucia Coast is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109318, Turbidity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 12735
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 52
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Coastal Confluences (CC) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 2 of 52 samples exceed the criterion for Turbidity(NTU).
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses. Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Sigler et al. (1984) states that turbidities of 25 NTU's or greater caused reduction in juvenile salmonid growth due to interference with their ability to find food.
Guideline Reference: Effects of chronic turbidity on density and growth of steelheads and coho salmon. Transactions of the American Fisheries Society 113:142-150
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 4/24/2001-12/20/2006. CCAMP Coastal confluence monitoring is conducted monthly (with the exception of April 2003 - December 2003) and is ongoing.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109318, Turbidity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51919
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 25
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 1 of 25 samples exceed the criterion for Turbidity(NTU).
Data Reference: Santa Lucia Watershed Rotation field data 2009
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline: Turbidities of 40 NTU or greater can cause a reduction in piscivorous fish (largemouth bass) growth due to interference with their ability to find food (Shoup, D.E. and Wahl D.H., 2009).
Guideline Reference: The Effects of Turbidity on Prey Selection by Piscivorous Largemouth Bass
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 2 monitoring sites [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road, 310SLM-San Luis Obispo Creek at Mission Plaza]
Temporal Representation: Data was collected over the time period 1/21/2009-12/16/2009.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109318, Turbidity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 182949
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 101
Number of Exceedances: 7
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 7 of 101 samples exceeded the water quality threshold for Turbidity.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses. (Basin Plan)
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Turbidities of 25 NTU or greater can cause a reduction in juvenile salmonid growth due to interference with their ability to find food (Sigler et al. 1984).
Guideline Reference: Effects of chronic turbidity on density and growth of steelheads and coho salmon. Transactions of the American Fisheries Society 113:142-150
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2019-02-06
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109318, Turbidity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 182948
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 13
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 13 samples exceeded the water quality threshold for Turbidity.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses. (Basin Plan)
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Turbidities of 25 NTU or greater can cause a reduction in juvenile salmonid growth due to interference with their ability to find food (Sigler et al. 1984).
Guideline Reference: Effects of chronic turbidity on density and growth of steelheads and coho salmon. Transactions of the American Fisheries Society 113:142-150
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-02-26 and 2016-07-13
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109318, Turbidity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 182950
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 12 samples exceeded the water quality threshold for Turbidity.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Turbidities of 40 NTU or greater can cause a reduced foraging efficiency and a shift in prey selection in piscivorous fish (largemouth bass) due to interference with their ability to find prey (Shoup, D.E. and Wahl D.H., 2009).
Guideline Reference: The Effects of Turbidity on Prey Selection by Piscivorous Largemouth Bass
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-02-26 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109318, Turbidity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 183163
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 101
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 4 of 101 samples exceeded the water quality threshold for Turbidity.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Turbidities of 40 NTU or greater can cause a reduced foraging efficiency and a shift in prey selection in piscivorous fish (largemouth bass) due to interference with their ability to find prey (Shoup, D.E. and Wahl D.H., 2009).
Guideline Reference: The Effects of Turbidity on Prey Selection by Piscivorous Largemouth Bass
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2019-02-06
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109318, Turbidity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 182218
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 13
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 13 samples exceeded the water quality threshold for Turbidity.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Turbidities of 40 NTU or greater can cause a reduced foraging efficiency and a shift in prey selection in piscivorous fish (largemouth bass) due to interference with their ability to find prey (Shoup, D.E. and Wahl D.H., 2009).
Guideline Reference: The Effects of Turbidity on Prey Selection by Piscivorous Largemouth Bass
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-02-26 and 2016-07-13
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109318, Turbidity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 182054
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 12 samples exceeded the water quality threshold for Turbidity.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses. (Basin Plan)
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Turbidities of 25 NTU or greater can cause a reduction in juvenile salmonid growth due to interference with their ability to find food (Sigler et al. 1984).
Guideline Reference: Effects of chronic turbidity on density and growth of steelheads and coho salmon. Transactions of the American Fisheries Society 113:142-150
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-02-26 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109318, Turbidity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 12486
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Diurnal Dissolved Oxygen Sampling (DO) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceed the criterion for Turbidity(NTU).
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses. Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Sigler et al. (1984) states that turbidities of 25 NTU's or greater caused reduction in juvenile salmonid growth due to interference with their ability to find food.
Guideline Reference: Effects of chronic turbidity on density and growth of steelheads and coho salmon. Transactions of the American Fisheries Society 113:142-150
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 7/3/2001-8/30/2001. Diurnal monitoring conducted in summer months at all CCAMP monitoring sites.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109318, Turbidity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51932
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 39
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 3 of 39 samples exceed the criterion for Turbidity(NTU).
Data Reference: Coastal Confluences field data 2007-2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses. (Basin Plan)
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline: Turbidities of 25 NTU or greater can cause a reduction in juvenile salmonid growth due to interference with their ability to find food (Sigler et al. 1984).
Guideline Reference: Effects of chronic turbidity on density and growth of steelheads and coho salmon. Transactions of the American Fisheries Society 113:142-150
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 1/18/2007-6/22/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109318, Turbidity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 12734
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 52
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Coastal Confluences (CC) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 2 of 52 samples exceed the criterion for Turbidity(NTU).
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses. Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Sigler et al. (1984) states that turbidities of 25 NTU's or greater caused reduction in juvenile salmonid growth due to interference with their ability to find food.
Guideline Reference: Effects of chronic turbidity on density and growth of steelheads and coho salmon. Transactions of the American Fisheries Society 113:142-150
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 4/24/2001-12/20/2006. CCAMP Coastal confluence monitoring is conducted monthly (with the exception of April 2003 - December 2003) and is ongoing.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
 
DECISION ID
109319
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Zinc
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the Clean Water Act (CWA) section 303(d) List under section 3.1 and 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment. The pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the Section 303(d) List.

A total of 17 lines of evidence are available in the administrative record to assess this pollutant. Sample and exceedance counts for the lines of evidence with the fraction identified as “none” or “not recorded” are grouped together with those having the fraction “total”, based on the analytical method used. For the water matrix, a total of zero of 118 samples exceed the water quality objective for the agricultural supply beneficial use, zero of 118 samples exceed the water quality objective for the cold freshwater habitat beneficial use and zero of 118 samples exceed the water quality objective for the warm freshwater habitat beneficial use. For the sediment matrix, a total of zero of four samples exceed the evaluation guideline for the cold freshwater habitat beneficial use and zero of four samples exceed the evaluation guideline for the warm freshwater habitat beneficial use.

After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. For the water matrix, a total of zero of 118 samples exceed the water quality objective for the agricultural supply beneficial use, zero of 118 samples exceed the water quality objective for the cold freshwater habitat beneficial use and zero of 118 samples exceed the water quality objective for the warm freshwater habitat beneficial use. For the sediment matrix, a total of zero of four samples exceed the evaluation guideline for the cold freshwater habitat beneficial use and zero of four samples exceed the evaluation guideline for the warm freshwater habitat beneficial use. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109319, Zinc
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 156674
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 13
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 13 samples exceeded the water quality threshold for Zinc.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109319, Zinc
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 156671
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 13
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 13 samples exceeded the water quality threshold for Zinc.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109319, Zinc
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 17719
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Zinc.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for zinc is 459 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109319, Zinc
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 17758
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Zinc.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for zinc is 459 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109319, Zinc
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 17734
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Zinc.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for zinc is 459 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109319, Zinc
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57919
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Zinc.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for zinc is 459 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109319, Zinc
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57918
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Zinc.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for zinc is 459 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109319, Zinc
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 156914
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 13
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 13 samples exceeded the water quality threshold for Zinc.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109319, Zinc
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 155830
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 7 samples exceeded the evaluation guideline for Zinc .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for zinc in 459 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2018-06-13
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109319, Zinc
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 156740
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 92
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 92 samples exceeded the water quality threshold for Zinc.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2011-01-06 and 2018-12-06
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109319, Zinc
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 156867
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 13
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 13 samples exceeded the water quality threshold for Zinc.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109319, Zinc
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 156847
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 92
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 92 samples exceeded the water quality threshold for Zinc.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan and identified as the maximum concentration for zinc for irrigation supply as 2.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2011-01-06 and 2018-12-06
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109319, Zinc
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 156787
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 13
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 13 samples exceeded the water quality threshold for Zinc.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan and identified as the maximum concentration for zinc for irrigation supply as 2.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109319, Zinc
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 156831
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 92
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 92 samples exceeded the water quality threshold for Zinc.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2011-01-06 and 2018-12-06
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109319, Zinc
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 155985
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 7 samples exceeded the evaluation guideline for Zinc .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for zinc in 459 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2018-06-13
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109319, Zinc
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 156673
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 13
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 13 samples exceeded the water quality threshold for Zinc.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan and identified as the maximum concentration for zinc for irrigation supply as 2.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109319, Zinc
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 17757
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Zinc.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for zinc is 459 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
 
DECISION ID
109309
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: pH
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

Sixty lines of evidence is available in the administrative record to assess this pollutant. Nine of the 281 samples exceed the maximum pH water quality objective for Municipal and Domestic Supply, Contact and Non-contact Recreation beneficial uses. Two of the 281 samples exceed the maximum pH water quality objective for Agriculture Supply, Cold and Warm Freshwater Habitat.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Nine of the 281 samples exceed the maximum pH water quality objective for Municipal and Domestic Supply, Contact and Non-contact Recreation beneficial uses, 2 of the 281 samples exceed the maximum pH water quality objective for Agriculture Supply, Cold and Warm Freshwater Habitat and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 11810
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 59
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Coastal Confluences (CC) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 1 of 59 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin, Section II.A.2. Municipal and Domestic Supply Objectives, Section II.A.2.a states the following: The pH value shall neither be depressed below 6.5 or raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 4/24/2001-12/20/2006. CCAMP Coastal confluence monitoring is conducted monthly (with the exception of April 2003 - December 2003) and is ongoing.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51971
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 41
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 41 samples exceed the criterion for pH.
Data Reference: Coastal Confluences field data 2007-2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The pH value shall not be depressed below 6.5 or raised above 8.3 (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 1/18/2007-6/22/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 11831
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Diurnal Dissolved Oxygen Sampling (DO) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 7 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin, Section II.A.2. Municipal and Domestic Supply Objectives, Section II.A.2.a states the following: The pH value shall neither be depressed below 6.5 or raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 7/3/2001-8/7/2006. Diurnal monitoring conducted in summer months at all CCAMP monitoring sites.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 11847
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Diurnal Dissolved Oxygen Sampling (DO) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 7 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for non-contact water recreation uses (Section II.A.2. Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries, II.A.2.a) states the following: pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 7/3/2001-8/7/2006. Diurnal monitoring conducted in summer months at all CCAMP monitoring sites.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 11812
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 59
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Coastal Confluences (CC) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 1 of 59 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for non-contact water recreation uses (Section II.A.2. Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries, II.A.2.a) states the following: pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 4/24/2001-12/20/2006. CCAMP Coastal confluence monitoring is conducted monthly (with the exception of April 2003 - December 2003) and is ongoing.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 52009
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 41
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 41 samples exceed the criterion for pH.
Data Reference: Coastal Confluences field data 2007-2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The pH value shall neither be depressed below 6.5 nor raised above 8.3 (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 1/18/2007-6/22/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 179788
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Dissolved Oxygen Study data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for pH.
Data Reference: Field data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for cold fresh water habitat (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 7.0 nor raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2012-07-16 and 2012-07-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 178820
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for municipal and domestic supply (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2016-07-13
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 179197
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for water contact recreation (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2014-06-04 and 2018-06-13
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 178447
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 13
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 3 of 13 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for municipal and domestic supply (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 178098
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 100
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 2 of 100 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for cold fresh water habitat (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 7.0 nor raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2019-03-06
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 179083
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines listed in the Central Coast Basin Plan and identified as the level that severe problems may occur when pH is greater than 8.4 or less than 6.5 in irrigation supply water.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2014-06-04 and 2018-06-13
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 177716
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines listed in the Central Coast Basin Plan and identified as the level that severe problems may occur when pH is greater than 8.4 or less than 6.5 in irrigation supply water.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2016-07-13
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 178511
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Dissolved Oxygen Study data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for pH.
Data Reference: Field data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for water contact recreation (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2012-07-16 and 2012-07-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 177983
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 13
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 13 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines listed in the Central Coast Basin Plan and identified as the level that severe problems may occur when pH is greater than 8.4 or less than 6.5 in irrigation supply water.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 179235
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Dissolved Oxygen Study data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for pH.
Data Reference: Field data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for municipal and domestic supply (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2012-07-16 and 2012-07-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 178012
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for municipal and domestic supply (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2014-06-04 and 2018-06-13
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 179878
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 100
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 2 of 100 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for municipal and domestic supply (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2019-03-06
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 179731
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for cold fresh water habitat (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 7.0 nor raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2014-06-04 and 2018-06-13
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 178512
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 13
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 3 of 13 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for water contact recreation (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 177630
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 100
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 2 of 100 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for warm fresh water habitat (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 7.0 nor raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2019-03-06
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 177691
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for non-contact water recreation (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2014-06-04 and 2018-06-13
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 177710
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 100
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 2 of 100 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for water contact recreation (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2019-03-06
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 177146
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Dissolved Oxygen Study data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for pH.
Data Reference: Field data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines listed in the Central Coast Basin Plan and identified as the level that severe problems may occur when pH is greater than 8.4 or less than 6.5 in irrigation supply water.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2012-07-16 and 2012-07-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 177633
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 13
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 13 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for warm fresh water habitat (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 7.0 nor raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 179613
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 13
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 13 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for cold fresh water habitat (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 7.0 nor raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 179876
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for cold fresh water habitat (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 7.0 nor raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2016-07-13
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 177692
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for warm fresh water habitat (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 7.0 nor raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2016-07-13
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 177055
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 100
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 2 of 100 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines listed in the Central Coast Basin Plan and identified as the level that severe problems may occur when pH is greater than 8.4 or less than 6.5 in irrigation supply water.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2019-03-06
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 177211
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Dissolved Oxygen Study data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for pH.
Data Reference: Field data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for warm fresh water habitat (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 7.0 nor raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2012-07-16 and 2012-07-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 177274
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for warm fresh water habitat (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 7.0 nor raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2014-06-04 and 2018-06-13
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 178038
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Dissolved Oxygen Study data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for pH.
Data Reference: Field data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for non-contact water recreation (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2012-07-16 and 2012-07-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 178059
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 13
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 3 of 13 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for non-contact water recreation (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2015-12-16
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 52010
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 25
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 3 of 25 samples exceed the criterion for pH.
Data Reference: Santa Lucia Watershed Rotation field data 2009
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The pH value shall neither be depressed below 6.5 nor raised above 8.3 (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 2 monitoring sites [ 310SLM-San Luis Obispo Creek at Mission Plaza, 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/21/2009-12/16/2009.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 11628
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Santa Lucia (SantaLucia) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 16 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for non-contact water recreation uses (Section II.A.2. Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries, II.A.2.a) states the following: pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/15/2002-3/19/2003. Santa Lucia Coast is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51916
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 41
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 41 samples exceed the criterion for pH.
Data Reference: Coastal Confluences field data 2007-2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The pH value shall not be depressed below 7.0 or raised above 8.5 (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 1/18/2007-6/22/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 11813
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 59
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Coastal Confluences (CC) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 59 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin, General Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: For waters not mentioned by a specific beneficial use, the pH value shall not be depressed below 7.0 or raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 4/24/2001-12/20/2006. CCAMP Coastal confluence monitoring is conducted monthly (with the exception of April 2003 - December 2003) and is ongoing.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51917
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 25
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 25 samples exceed the criterion for pH.
Data Reference: Santa Lucia Watershed Rotation field data 2009
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The pH value shall not be depressed below 7.0 or raised above 8.5 (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 2 monitoring sites [ 310SLM-San Luis Obispo Creek at Mission Plaza, 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/21/2009-12/16/2009.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 11629
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Santa Lucia (SantaLucia) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 16 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin, General Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: For waters not mentioned by a specific beneficial use, the pH value shall not be depressed below 7.0 or raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/15/2002-3/19/2003. Santa Lucia Coast is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 11848
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Diurnal Dissolved Oxygen Sampling (DO) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 7 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin, General Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: For waters not mentioned by a specific beneficial use, the pH value shall not be depressed below 7.0 or raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 7/3/2001-8/7/2006. Diurnal monitoring conducted in summer months at all CCAMP monitoring sites.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 11811
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 59
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Coastal Confluences (CC) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 1 of 59 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for water contact recreation uses (Section II.A.2. Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries, II.A.2.a) states the following: pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 4/24/2001-12/20/2006. CCAMP Coastal confluence monitoring is conducted monthly (with the exception of April 2003 - December 2003) and is ongoing.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51991
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 41
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 41 samples exceed the criterion for pH.
Data Reference: Coastal Confluences field data 2007-2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The pH value shall neither be depressed below 6.5 nor raised above 8.3 (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 1/18/2007-6/22/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 52006
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 25
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 3 of 25 samples exceed the criterion for pH.
Data Reference: Santa Lucia Watershed Rotation field data 2009
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The pH value shall neither be depressed below 6.5 nor raised above 8.3 (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 2 monitoring sites [ 310SLM-San Luis Obispo Creek at Mission Plaza, 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/21/2009-12/16/2009.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 11832
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Diurnal Dissolved Oxygen Sampling (DO) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 7 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for water contact recreation uses (Section II.A.2. Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries, II.A.2.a) states the following: pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 7/3/2001-8/7/2006. Diurnal monitoring conducted in summer months at all CCAMP monitoring sites.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 11627
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Santa Lucia (SantaLucia) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 16 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for water contact recreation uses (Section II.A.2. Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries, II.A.2.a) states the following: pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/15/2002-3/19/2003. Santa Lucia Coast is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 179677
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for water contact recreation (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2016-07-13
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 179198
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 100
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 2 of 100 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for non-contact water recreation (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2010-07-21 and 2019-03-06
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 177734
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for non-contact water recreation (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-01-29 and 2016-07-13
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 11793
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 59
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Coastal Confluences (CC) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 59 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines provided in Table 3-3 (Central Coast Waterboard Basin Plan, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). In Table 3-3 of the Basin Plan (page III-8), water quality guidelines state that severe problems may occur when pH is greater than 8.4 or less than 6.5 in irrigation supply water.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 4/24/2001-12/20/2006. CCAMP Coastal confluence monitoring is conducted monthly (with the exception of April 2003 - December 2003) and is ongoing.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 11829
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Diurnal Dissolved Oxygen Sampling (DO) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 7 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines provided in Table 3-3 (Central Coast Waterboard Basin Plan, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). In Table 3-3 of the Basin Plan (page III-8), water quality guidelines state that severe problems may occur when pH is greater than 8.4 or less than 6.5 in irrigation supply water.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 7/3/2001-8/7/2006. Diurnal monitoring conducted in summer months at all CCAMP monitoring sites.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 52042
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 25
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 25 samples exceed the criterion for pH.
Data Reference: Santa Lucia Watershed Rotation field data 2009
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines provided in Table 3-3 (Central Coast Region Basin Plan, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). In Table 3-3 of the Basin Plan (page III-8), water quality guidelines state that severe problems may occur when pH is greater than 8.4 or less than 6.5 in irrigation supply water.
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 2 monitoring sites [ 310SLM-San Luis Obispo Creek at Mission Plaza, 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/21/2009-12/16/2009.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 52041
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 41
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 41 samples exceed the criterion for pH.
Data Reference: Coastal Confluences field data 2007-2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines provided in Table 3-3 (Central Coast Region Basin Plan, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). In Table 3-3 of the Basin Plan (page III-8), water quality guidelines state that severe problems may occur when pH is greater than 8.4 or less than 6.5 in irrigation supply water.
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 1/18/2007-6/22/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 11609
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Santa Lucia (SantaLucia) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 16 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines provided in Table 3-3 (Central Coast Waterboard Basin Plan, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). In Table 3-3 of the Basin Plan (page III-8), water quality guidelines state that severe problems may occur when pH is greater than 8.4 or less than 6.5 in irrigation supply water.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/15/2002-3/19/2003. Santa Lucia Coast is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51931
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 25
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 25 samples exceed the criterion for pH.
Data Reference: Santa Lucia Watershed Rotation field data 2009
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The pH value shall not be depressed below 7.0 or raised above 8.5 (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 2 monitoring sites [ 310SLM-San Luis Obispo Creek at Mission Plaza, 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/21/2009-12/16/2009.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 11830
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Diurnal Dissolved Oxygen Sampling (DO) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 7 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin, General Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: For waters not mentioned by a specific beneficial use, the pH value shall not be depressed below 7.0 or raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 7/3/2001-8/7/2006. Diurnal monitoring conducted in summer months at all CCAMP monitoring sites.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51930
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 41
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 41 samples exceed the criterion for pH.
Data Reference: Coastal Confluences field data 2007-2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The pH value shall not be depressed below 7.0 or raised above 8.5 (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 1/18/2007-6/22/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 11610
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Santa Lucia (SantaLucia) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 16 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin, General Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: For waters not mentioned by a specific beneficial use, the pH value shall not be depressed below 7.0 or raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/15/2002-3/19/2003. Santa Lucia Coast is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 11809
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 59
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Coastal Confluences (CC) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 59 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin, General Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: For waters not mentioned by a specific beneficial use, the pH value shall not be depressed below 7.0 or raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 4/24/2001-12/20/2006. CCAMP Coastal confluence monitoring is conducted monthly (with the exception of April 2003 - December 2003) and is ongoing.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 11626
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Santa Lucia (SantaLucia) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 16 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin, Section II.A.2. Municipal and Domestic Supply Objectives, Section II.A.2.a states the following: The pH value shall neither be depressed below 6.5 or raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/15/2002-3/19/2003. Santa Lucia Coast is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109309, pH
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51972
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 25
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 3 of 25 samples exceed the criterion for pH.
Data Reference: Santa Lucia Watershed Rotation field data 2009
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The pH value shall not be depressed below 6.5 or raised above 8.3 (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 2 monitoring sites [ 310SLM-San Luis Obispo Creek at Mission Plaza, 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/21/2009-12/16/2009.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
 
DECISION ID
109345
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Aluminum
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Sources: No Source Analysis Available
Expected TMDL Completion Date: 2035
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) List under section 3.1 of the Listing Policy.

Six lines of evidence are available in the administrative record to assess this pollutant. Three of 14 water samples exceed the evaluation guideline applied to protect commercial or recreational collection of fish, shellfish, or organisms beneficial use(s) and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy. Zero of 14 water samples exceed the evaluation guideline applied to protect the agricultural supply beneficial use (AGR). This sample size is insufficient to determine, with the power and confidence of the Listing Policy, the AGR beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported using table 3.1. Therefore, the use support rating for AGR is set to 'insufficient information'.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Three of 14 water samples exceed the evaluation guideline applied to protect commercial or recreational collection of fish, shellfish, or organisms beneficial use(s) and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 109345, Aluminum
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 157195
 
Pollutant: Aluminum
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Aluminum.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan and identified as the maximum concentration for aluminum for irrigation supply as 5.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109345, Aluminum
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 157285
 
Pollutant: Aluminum
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 3
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 1 of 3 samples exceeded the water quality threshold for Aluminum.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The 4-day average for fish and water consumption is 0.087 mg/L (USEPA National Recommended Water Quality Criteria).
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109345, Aluminum
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 157218
 
Pollutant: Aluminum
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Aluminum.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan and identified as the maximum concentration for aluminum for irrigation supply as 5.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109345, Aluminum
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 157264
 
Pollutant: Aluminum
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Aluminum.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan and identified as the maximum concentration for aluminum for irrigation supply as 5.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2013-06-10 and 2017-12-07
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109345, Aluminum
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 157196
 
Pollutant: Aluminum
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 2
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 1 of 2 samples exceeded the water quality threshold for Aluminum.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The 4-day average for fish and water consumption is 0.087 mg/L (USEPA National Recommended Water Quality Criteria).
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109345, Aluminum
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 157330
 
Pollutant: Aluminum
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 9
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 1 of 9 samples exceeded the water quality threshold for Aluminum.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The 4-day average for fish and water consumption is 0.087 mg/L (USEPA National Recommended Water Quality Criteria).
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2013-06-10 and 2017-12-07
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109299
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Lead
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: No Source Analysis Available
Expected TMDL Completion Date: 2035
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 and 3.6 of the Listing Policy. Under section 3.1 at least one line of evidence is necessary to assess listing status, but under section 3.6 at least two lines of evidence are necessary to assess listing status and the pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the section 303(d) List.

Twenty lines of evidence are available in the administrative record to assess this pollutant. Where the fraction is none, staff assumed that the fraction was total and summed sample and exceedance counts for the purpose of making this decision.

Zero of the 12 dissolved lead samples in water exceed the water quality objective aquatic life beneficial uses.

Zero of the 12 dissolved lead samples in water exceed the evaluation guideline for Agriculture Supply and 3 of the 12 dissolved lead samples in water exceed the evaluation guideline for Municipal and Domestic Supply.

Zero of ten sediment samples exceed the evaluation guideline used to interpret the narrative water quality objective for aquatic life protection.

After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Three of the 12 dissolved lead samples in water exceed the evaluation guideline for Municipal and Domestic Supply. These do exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) List because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109299, Lead
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 168218
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Lead.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan and identified as the maximum concentration for lead for livestock watering as 0.1 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109299, Lead
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 168195
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Lead.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109299, Lead
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 167863
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Lead.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2013-06-10 and 2017-12-07
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109299, Lead
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 168031
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 3
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 1 of 3 samples exceeded the water quality threshold for Lead.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The California Public Health Goal for lead in sources of drinking water is 0.0002 mg/L. (OEHHA 2009)
Guideline Reference: Public Health Goal for Lead in Drinking Water
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109299, Lead
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 154644
 
Pollutant: Lead
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 7 samples exceeded the evaluation guideline for Lead .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for lead in 128 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2018-06-13
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109299, Lead
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 168079
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Lead.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The California Public Health Goal for lead in sources of drinking water is 0.0002 mg/L. (OEHHA 2009)
Guideline Reference: Public Health Goal for Lead in Drinking Water
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2013-06-10 and 2017-12-07
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109299, Lead
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 168208
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 2 of 2 samples exceeded the water quality threshold for Lead.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The California Public Health Goal for lead in sources of drinking water is 0.0002 mg/L. (OEHHA 2009)
Guideline Reference: Public Health Goal for Lead in Drinking Water
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109299, Lead
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 168035
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Lead.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan and identified as the maximum concentration for lead for livestock watering as 0.1 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109299, Lead
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 168081
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Lead.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109299, Lead
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 17152
 
Pollutant: Lead
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Lead.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for lead is 128 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109299, Lead
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 17173
 
Pollutant: Lead
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Lead.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for lead is 128 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109299, Lead
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 17186
 
Pollutant: Lead
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Lead.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for lead is 128 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/26/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109299, Lead
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 17153
 
Pollutant: Lead
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Lead.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: In fresh water sediments the probable effects level (predictive of sediment toxicity) for lead is 128 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109299, Lead
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57882
 
Pollutant: Lead
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Lead.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for lead is 128 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109299, Lead
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57881
 
Pollutant: Lead
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Lead.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for lead is 128 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109299, Lead
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 168098
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Lead.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLM)
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109299, Lead
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 168016
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Santa Lucia Rotation data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Lead.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLV)
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2015-11-19
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109299, Lead
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 168362
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Lead.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan and identified as the maximum concentration for lead for livestock watering as 0.1 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2013-06-10 and 2017-12-07
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109299, Lead
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 154690
 
Pollutant: Lead
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and the results are as follows: 0 of the 7 samples exceeded the evaluation guideline for Lead .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for lead in 128 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310SLB.
Temporal Representation: Data for this waterbody were collected over the date range 2010-06-21 to 2018-06-13
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109299, Lead
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 168157
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Lead.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2013-06-10 and 2017-12-07
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
109316
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Toxicity
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: No Source Analysis Available
Expected TMDL Completion Date: 2035
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) List under section 3.1 and section 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Twenty-six lines of evidence are available in the administrative record to assess this pollutant. One sample can have multiple toxicity test results (or endpoints) but will be counted only once. One sample is defined as being collected on the same day at the same location.

Sixteen LOEs summarize water samples. Eight out of 17 water samples were toxic to test organisms (exhibited a significant increase in mortality, decrease in cell density, decrease in growth or reproduction compared to the laboratory control) and therefore exceeded the narrative general water quality objective for toxicity, set to protect for aquatic life beneficial uses.

Ten LOEs summarize sediment samples. Zero out of 12 samples were toxic to test organisms (exhibited a significant increase in mortality, decrease in cell density, decrease in growth or reproduction compared to the laboratory control) which does not exceed the narrative general water quality objective for toxicity, set to protect for aquatic life beneficial uses.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for placing this water segment-pollutant combination on the section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Eight out of 17 water samples were toxic to test organisms relative to the control and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) List because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109316, Toxicity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 23972
 
Pollutant: Invertebrate Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Toxicity, Hyalella azteca Survival (%) 10 days. Toxicity is defined by SWAMP (2004) as follows: Significant toxicity in the survival endpoint when compared to the negative control based on a statistical test with alpha of less than 5%, and less than the evaluation threshold (both criteria are met).
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Significant reduction of survival of test organism relative to the control (alpha < 0.05) and test organism survival is 20% less than the control survival.
Guideline Reference: Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109316, Toxicity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 23973
 
Pollutant: Invertebrate Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (03SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Toxicity, Hyalella azteca Survival (%) 10 days. Toxicity is defined by SWAMP (2004) as follows: Significant toxicity in the survival endpoint when compared to the negative control based on a statistical test with alpha of less than 5%, and less than the evaluation threshold (both criteria are met).
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Significant reduction of survival of test organism relative to the control (alpha < 0.05) and test organism survival is 20% less than the control survival.
Guideline Reference: Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 4/1/2004. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109316, Toxicity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 148691
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 1 of the 8 samples collected by SWAMP Stream Pollution Trends for San Luis Obispo Creek (below Osos Street) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Growth (wt/surv indiv), Chironomus dilutus, for Survival, Hyalella azteca, for Survival, Chironomus dilutus, for Ash Free Dry Mass, Chironomus dilutus, for Growth (wt/surv indiv)
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Central Coastal Basin Plan 2019).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( 310SLB )
Temporal Representation: The samples were collected between the dates of 2010-06-21 and 2018-06-13.
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109316, Toxicity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 148629
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 0 of the 2 samples collected by SWAMP RWB3 CCAMP Santa Lucia Rotation for San Luis Obispo Creek (below Osos Street) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Pimephales promelas, for Survival, Ceriodaphnia dubia, for Young/female, Pimephales promelas, for Biomass (wt/orig indiv), Ceriodaphnia dubia, for Survival, Selenastrum capricornutum, for Total Cell Count, Hyalella azteca, for Survival
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Significant reduction of survival of test organism relative to the control (alpha < 0.05) and test organism survival is 20% less than the control survival.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
Guideline Reference: SWAMP_Memo_Toxicity_Data_Intrepretation
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( 310SLM )
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16.
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109316, Toxicity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 148677
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 1 of the 8 samples collected by SWAMP Stream Pollution Trends for San Luis Obispo Creek (below Osos Street) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Growth (wt/surv indiv), Chironomus dilutus, for Survival, Hyalella azteca, for Survival, Chironomus dilutus, for Ash Free Dry Mass, Chironomus dilutus, for Growth (wt/surv indiv)
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Central Coastal Basin Plan 2019).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( 310SLB )
Temporal Representation: The samples were collected between the dates of 2010-06-21 and 2018-06-13.
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109316, Toxicity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 148628
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 0 of the 2 samples collected by SWAMP RWB3 CCAMP Santa Lucia Rotation for San Luis Obispo Creek (below Osos Street) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Pimephales promelas, for Survival, Ceriodaphnia dubia, for Young/female, Pimephales promelas, for Biomass (wt/orig indiv), Ceriodaphnia dubia, for Survival, Selenastrum capricornutum, for Total Cell Count, Hyalella azteca, for Survival
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Significant reduction of survival of test organism relative to the control (alpha < 0.05) and test organism survival is 20% less than the control survival.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
Guideline Reference: SWAMP_Memo_Toxicity_Data_Intrepretation
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( 310SLM )
Temporal Representation: The samples were collected between the dates of 2015-09-09 and 2015-11-16.
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109316, Toxicity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 148626
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 5
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 5 of the 5 samples collected by SWAMP RWB3 CCAMP Santa Lucia Rotation for San Luis Obispo Creek (below Osos Street) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Ceriodaphnia dubia, for Survival, Ceriodaphnia dubia, for Young/female, Chironomus dilutus, for Survival, Selenastrum capricornutum, for Total Cell Count, Hyalella azteca, for Survival, Pimephales promelas, for Biomass (wt/orig indiv), Pimephales promelas, for Survival, Chironomus dilutus, for Ash Free Dry Mass
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Significant reduction of survival of test organism relative to the control (alpha < 0.05) and test organism survival is 20% less than the control survival.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
Guideline Reference: SWAMP_Memo_Toxicity_Data_Intrepretation
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( 310SLV )
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2016-07-13.
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109316, Toxicity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 148622
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 5
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 5 of the 5 samples collected by SWAMP RWB3 CCAMP Santa Lucia Rotation for San Luis Obispo Creek (below Osos Street) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Ceriodaphnia dubia, for Survival, Ceriodaphnia dubia, for Young/female, Chironomus dilutus, for Survival, Selenastrum capricornutum, for Total Cell Count, Hyalella azteca, for Survival, Pimephales promelas, for Biomass (wt/orig indiv), Pimephales promelas, for Survival, Chironomus dilutus, for Ash Free Dry Mass
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Significant reduction of survival of test organism relative to the control (alpha < 0.05) and test organism survival is 20% less than the control survival.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
Guideline Reference: SWAMP_Memo_Toxicity_Data_Intrepretation
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( 310SLV )
Temporal Representation: The samples were collected between the dates of 2015-05-20 and 2016-07-13.
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109316, Toxicity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 149005
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 2
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 2 of the 4 samples collected by SWAMP RWB3 CCAMP Coastal Confluences for San Luis Obispo Creek (below Osos Street) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Ceriodaphnia dubia, for Survival, Selenastrum capricornutum, for Total Cell Count, Pimephales promelas, for Biomass (wt/orig indiv), Ceriodaphnia dubia, for Young/female, Pimephales promelas, for Survival, Hyalella azteca, for Survival
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Significant reduction of survival of test organism relative to the control (alpha < 0.05) and test organism survival is 20% less than the control survival.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
Guideline Reference: SWAMP_Memo_Toxicity_Data_Intrepretation
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( 310SLB )
Temporal Representation: The samples were collected between the dates of 2010-02-24 and 2015-11-16.
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109316, Toxicity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 148608
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 0 of the 1 samples collected by SWAMP RWB3 CCAMP SpecialStudies for San Luis Obispo Creek (below Osos Street) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Chironomus dilutus, for Ash Free Dry Mass, Hyalella azteca, for Survival, Chironomus dilutus, for Survival, Ceriodaphnia dubia, for Survival
Data Reference: Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Significant reduction of survival of test organism relative to the control (alpha < 0.05) and test organism survival is 20% less than the control survival.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
Guideline Reference: SWAMP_Memo_Toxicity_Data_Intrepretation
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( 310SLV )
Temporal Representation: The samples were collected between the dates of 2018-01-17 and 2018-01-17.
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109316, Toxicity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 148827
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 2
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 2 of the 4 samples collected by SWAMP RWB3 CCAMP Coastal Confluences for San Luis Obispo Creek (below Osos Street) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Ceriodaphnia dubia, for Survival, Selenastrum capricornutum, for Total Cell Count, Pimephales promelas, for Biomass (wt/orig indiv), Ceriodaphnia dubia, for Young/female, Pimephales promelas, for Survival, Hyalella azteca, for Survival
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Significant reduction of survival of test organism relative to the control (alpha < 0.05) and test organism survival is 20% less than the control survival.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
Guideline Reference: SWAMP_Memo_Toxicity_Data_Intrepretation
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( 310SLB )
Temporal Representation: The samples were collected between the dates of 2010-02-24 and 2015-11-16.
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109316, Toxicity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 148618
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 0 of the 1 samples collected by SWAMP RWB3 CCAMP SpecialStudies for San Luis Obispo Creek (below Osos Street) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Chironomus dilutus, for Ash Free Dry Mass, Hyalella azteca, for Survival, Chironomus dilutus, for Survival, Ceriodaphnia dubia, for Survival
Data Reference: Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Significant reduction of survival of test organism relative to the control (alpha < 0.05) and test organism survival is 20% less than the control survival.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
Guideline Reference: SWAMP_Memo_Toxicity_Data_Intrepretation
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( 310SLV )
Temporal Representation: The samples were collected between the dates of 2018-01-17 and 2018-01-17.
Environmental Conditions:
QAPP Information: SWAMP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109316, Toxicity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 24277
 
Pollutant: Vertebrate Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Toxicity, Pimephales promelas Survival (%) 7 days. Toxicity is defined by SWAMP (2004) as follows: Significant toxicity in the survival endpoint when compared to the negative control based on a statistical test with alpha of less than 5%, and less than the evaluation threshold (both criteria are met).
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Significant reduction of survival of test organism relative to the control (alpha < 0.05) and test organism survival is 20% less than the control survival.
Guideline Reference: Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/19/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109316, Toxicity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 24276
 
Pollutant: Vertebrate Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Toxicity, Pimephales promelas Survival (%) 7 days. Toxicity is defined by SWAMP (2004) as follows: Significant toxicity in the survival endpoint when compared to the negative control based on a statistical test with alpha of less than 5%, and less than the evaluation threshold (both criteria are met).
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Significant reduction of survival of test organism relative to the control (alpha < 0.05) and test organism survival is 20% less than the control survival.
Guideline Reference: Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/19/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109316, Toxicity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 80333
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Two samples were collected to evaluate water toxicity. One of the samples exhibited significant toxicity to Selenastrum capricornutum total cell count. The toxicity tests included total cell count of Selenastrum capricornutum, survival and growth of Ceriodaphnia dubia, and survival and biomass of Pimephales promelas. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Coastal Confluences 2008 2009
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 3 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
Guideline Reference: SWAMP_Memo_Toxicity_Data_Intrepretation
 
Spatial Representation: The samples were collected at station 310SLB - San Luis Creek at San Luis Bay Drive.
Temporal Representation: The samples were collected in March and September 2009.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2002) was followed.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109316, Toxicity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 80336
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Two samples were collected to evaluate water toxicity. None of the samples exhibited significant toxicity. The toxicity tests included total cell count of Selenastrum capricornutum, survival and growth of Ceriodaphnia dubia, and survival and biomass of Pimephales promelas. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Santa Lucia Watershed Rotation 2009
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 3 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
Guideline Reference: SWAMP_Memo_Toxicity_Data_Intrepretation
 
Spatial Representation: The samples were collected at station 310SLVxxx.
Temporal Representation: The samples were collected in March and September 2009.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2002) was followed.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109316, Toxicity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57916
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Two samples were collected to evaluate water toxicity. None of the samples exhibited significant toxicity. The toxicity tests included total cell count of Selenastrum capricornutum, survival and growth of Ceriodaphnia dubia, and survival and biomass of Pimephales promelas. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Santa Lucia Watershed Rotation 2009
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 3 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
Guideline Reference: SWAMP_Memo_Toxicity_Data_Intrepretation
 
Spatial Representation: The samples were collected at station 310SLVxxx.
Temporal Representation: The samples were collected in March and September 2009.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2002) was followed.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109316, Toxicity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57913
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Two samples were collected to evaluate water toxicity. One of the samples exhibited significant toxicity to Selenastrum capricornutum total cell count. The toxicity tests included total cell count of Selenastrum capricornutum, survival and growth of Ceriodaphnia dubia, and survival and biomass of Pimephales promelas. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Coastal Confluences 2008 2009
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 3 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
Guideline Reference: SWAMP_Memo_Toxicity_Data_Intrepretation
 
Spatial Representation: The samples were collected at station 310SLB - San Luis Creek at San Luis Bay Drive.
Temporal Representation: The samples were collected in March and September 2009.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2002) was followed.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109316, Toxicity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 80337
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to evaluate sediment toxicity. None of the samples exhibited significant toxicity. The toxicity tests included survival and growth of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 3 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
Guideline Reference: SWAMP_Memo_Toxicity_Data_Intrepretation
 
Spatial Representation: The samples were collected at station 310SLBxxx.
Temporal Representation: The samples were collected in June 2008.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2002) was followed.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109316, Toxicity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 80334
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to evaluate sediment toxicity. None of the samples exhibited significant toxicity. The toxicity tests included survival and growth of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Coastal Confluences 2008 2009
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 3 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
Guideline Reference: SWAMP_Memo_Toxicity_Data_Intrepretation
 
Spatial Representation: The samples were collected at station 310SLB - San Luis Creek at San Luis Bay Drive.
Temporal Representation: The samples were collected in May 2009.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2002) was followed.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109316, Toxicity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 80335
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to evaluate sediment toxicity. None of the samples exhibited significant toxicity. The toxicity tests included survival and growth of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Santa Lucia Watershed Rotation 2009
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 3 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
Guideline Reference: SWAMP_Memo_Toxicity_Data_Intrepretation
 
Spatial Representation: The samples were collected at station 310SLBxxx.
Temporal Representation: The samples were collected in May 2009.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2002) was followed.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109316, Toxicity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57915
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to evaluate sediment toxicity. None of the samples exhibited significant toxicity. The toxicity tests included survival and growth of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Santa Lucia Watershed Rotation 2009
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 3 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
Guideline Reference: SWAMP_Memo_Toxicity_Data_Intrepretation
 
Spatial Representation: The samples were collected at station 310SLBxxx.
Temporal Representation: The samples were collected in May 2009.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2002) was followed.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109316, Toxicity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57914
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to evaluate sediment toxicity. None of the samples exhibited significant toxicity. The toxicity tests included survival and growth of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Coastal Confluences 2008 2009
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 3 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
Guideline Reference: SWAMP_Memo_Toxicity_Data_Intrepretation
 
Spatial Representation: The samples were collected at station 310SLB - San Luis Creek at San Luis Bay Drive.
Temporal Representation: The samples were collected in May 2009.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2002) was followed.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109316, Toxicity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 24270
 
Pollutant: Invertebrate Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Toxicity, Ceriodaphnia dubia Survival (%) 7 days. Toxicity is defined by SWAMP (2004) as follows: Significant toxicity in the survival endpoint when compared to the negative control based on a statistical test with alpha of less than 5%, and less than the evaluation threshold (both criteria are met).
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Significant reduction of survival of test organism relative to the control (alpha < 0.05) and test organism survival is 20% less than the control survival.
Guideline Reference: Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/19/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109316, Toxicity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 24271
 
Pollutant: Invertebrate Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (00SW3001) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Toxicity, Ceriodaphnia dubia Survival (%) 7 days. Toxicity is defined by SWAMP (2004) as follows: Significant toxicity in the survival endpoint when compared to the negative control based on a statistical test with alpha of less than 5%, and less than the evaluation threshold (both criteria are met).
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Significant reduction of survival of test organism relative to the control (alpha < 0.05) and test organism survival is 20% less than the control survival.
Guideline Reference: Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected on a single day 3/19/2002. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109316, Toxicity
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57917
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to evaluate sediment toxicity. None of the samples exhibited significant toxicity. The toxicity tests included survival and growth of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 3 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
Guideline Reference: SWAMP_Memo_Toxicity_Data_Intrepretation
 
Spatial Representation: The samples were collected at station 310SLBxxx.
Temporal Representation: The samples were collected in June 2008.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2002) was followed.
QAPP Information Reference(s):
 
 
DECISION ID
109278
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Urea
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Sources: No Source Analysis Available
Expected TMDL Completion Date: 2035
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Two lines of evidence are available in the administrative record to assess this pollutant.

Two of the seventy-seven water samples exceed the evaluation guideline applied to protect for aquatic life beneficial uses.

After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Two of the seventy-seven water samples exceed the evaluation guideline applied to protect for aquatic life beneficial uses and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) List because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 109278, Urea
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 183156
 
Pollutant: Urea
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 77
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 2 of 77 samples exceeded the water quality threshold for Urea.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Urea is the USEPA Aquatic Life Benchmark of 11,500 ug/L for a nonvascular plant (acute) for Urea sulfate.
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2011-11-03 and 2018-12-06
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 109278, Urea
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 183177
 
Pollutant: Urea
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 77
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Confluences data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 2 of 77 samples exceeded the water quality threshold for Urea.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Urea is the USEPA Aquatic Life Benchmark of 11,500 ug/L for a nonvascular plant (acute) for Urea sulfate.
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310SLB)
Temporal Representation: The samples were collected between the dates of 2011-11-03 and 2018-12-06
Environmental Conditions:
QAPP Information: SWAMP 2008, SWAMP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
72636
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Chloride
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)(2016)
Revision Status Original
Sources: A Source Unknown
Expected TMDL Completion Date: 2027
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the CWA section 303(d) List under section 4.2 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status.

Four lines of evidence are available in the administrative record to assess this pollutant. Forty-seven of the 124 samples exceed the water quality objective for agricultural uses.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Forty-seven of the 124 samples exceed the water quality objective and this exceeds the allowable frequency listed in Table 4.2 of the Listing Policy.
4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 72636, Chloride
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 52002
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 24
Number of Exceedances: 9
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 9 of 24 samples exceed the criterion for Chloride.
Data Reference: Santa Lucia Watershed Rotation field data 2009
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines provided in Table 3-3 (Central Coast Waterboard Basin Plan, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). In Table 3-3 of the Basin Plan (page III-8), water quality guidelines state that severe problems may occur when chloride exceeds 106 mg/L in irrigation supply water.
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 2 monitoring sites [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road, 310SLM-San Luis Obispo Creek at Mission Plaza]
Temporal Representation: Data was collected over the time period 1/21/2009-12/16/2009.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 72636, Chloride
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 10001
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 52
Number of Exceedances: 15
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Coastal Confluences (CC) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 15 of 52 samples exceed the criterion for Chloride.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines provided in Table 3-3 (Central Coast Waterboard Basin Plan, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). In Table 3-3 of the Basin Plan (page III-8), water quality guidelines state that severe problems may occur when chloride exceeds 106 mg/L in irrigation supply water.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 4/24/2001-12/20/2006. CCAMP Coastal confluence monitoring is conducted monthly (with the exception of April 2003 - December 2003) and is ongoing.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 72636, Chloride
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51986
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 39
Number of Exceedances: 20
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 20 of 39 samples exceed the criterion for Chloride.
Data Reference: Coastal Confluences field data 2007-2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines provided in Table 3-3 (Central Coast Waterboard Basin Plan, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). In Table 3-3 of the Basin Plan (page III-8), water quality guidelines state that severe problems may occur when chloride exceeds 106 mg/L in irrigation supply water.
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 1/18/2007-6/22/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 72636, Chloride
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 10067
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 9
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Santa Lucia (SantaLucia) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 3 of 9 samples exceed the criterion for Chloride.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines provided in Table 3-3 (Central Coast Waterboard Basin Plan, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). In Table 3-3 of the Basin Plan (page III-8), water quality guidelines state that severe problems may occur when chloride exceeds 106 mg/L in irrigation supply water.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/15/2002-7/29/2002. Santa Lucia Coast is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
 
DECISION ID
72683
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Sodium
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)(2016)
Revision Status Original
Sources: A Source Unknown
Expected TMDL Completion Date: 2027
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the CWA section 303(d) List under section 4.2 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status.

Four lines of evidence are available in the administrative record to assess this pollutant. Eighty-nine of the 124 samples exceed the water quality objective for agricultural uses.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Eighty-nine of the 124 samples exceed the water quality objective and this exceeds the allowable frequency listed in Table 4.2 of the Listing Policy.
4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 72683, Sodium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 10004
 
Pollutant: Sodium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 52
Number of Exceedances: 40
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Coastal Confluences (CC) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 40 of 52 samples exceed the criterion for Sodium.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines provided in Table 3-3 (Central Coast Waterboard Basin Plan, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). In Table 3-3 of the Basin Plan (page III-8), water quality guidelines state that severe problems may occur when sodium exceeds 69 mg/L in irrigation supply water.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 4/24/2001-12/20/2006. CCAMP Coastal confluence monitoring is conducted monthly (with the exception of April 2003 - December 2003) and is ongoing.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 72683, Sodium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 52043
 
Pollutant: Sodium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 39
Number of Exceedances: 30
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 30 of 39 samples exceed the criterion for Sodium.
Data Reference: Coastal Confluences field data 2007-2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines provided in Table 3-3 (Central Coast Waterboard Basin Plan, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). In Table 3-3 of the Basin Plan (page III-8), water quality guidelines state that severe problems may occur when sodium exceeds 69 mg/L in irrigation supply water.
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 1/18/2007-6/22/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 72683, Sodium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 52057
 
Pollutant: Sodium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 24
Number of Exceedances: 10
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 10 of 24 samples exceed the criterion for Sodium.
Data Reference: Santa Lucia Watershed Rotation field data 2009
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines provided in Table 3-3 (Central Coast Waterboard Basin Plan, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). In Table 3-3 of the Basin Plan (page III-8), water quality guidelines state that severe problems may occur when sodium exceeds 69 mg/L in irrigation supply water.
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 2 monitoring sites [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road, 310SLM-San Luis Obispo Creek at Mission Plaza]
Temporal Representation: Data was collected over the time period 1/21/2009-12/16/2009.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 72683, Sodium
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 10082
 
Pollutant: Sodium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 9
Number of Exceedances: 9
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Santa Lucia (SantaLucia) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 9 of 9 samples exceed the criterion for Sodium.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines provided in Table 3-3 (Central Coast Waterboard Basin Plan, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). In Table 3-3 of the Basin Plan (page III-8), water quality guidelines state that severe problems may occur when sodium exceeds 69 mg/L in irrigation supply water.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/15/2002-7/29/2002. Santa Lucia Coast is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
 
DECISION ID
72740
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Boron
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Four lines of evidence are available in the administrative record to assess this pollutant. Zero of the 124 samples exceed the water quality objective for agricultural uses.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the 124 samples exceed the water quality objective and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 72740, Boron
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51985
 
Pollutant: Boron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 24
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 24 samples exceed the criterion for Boron, dissolved.
Data Reference: Santa Lucia Watershed Rotation field data 2009
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in Table 3-4 (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). Table 3-4 (page III-9) lists the maximum concentration for boron for irrigation supply is 0.75 mg/L.
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 2 monitoring sites [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road, 310SLM-San Luis Obispo Creek at Mission Plaza]
Temporal Representation: Data was collected over the time period 1/21/2009-12/16/2009.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 72740, Boron
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51984
 
Pollutant: Boron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 39
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 39 samples exceed the criterion for Boron, dissolved.
Data Reference: Coastal Confluences field data 2007-2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in Table 3-4 (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). Table 3-4 (page III-9) lists the maximum concentration for boron for irrigation supply is 0.75 mg/L.
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 1/18/2007-6/22/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 72740, Boron
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 10066
 
Pollutant: Boron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Santa Lucia (SantaLucia) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 9 samples exceed the criterion for Boron, dissolved.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in Table 3.4 (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). Table 3-4 (page III-9) lists the maximum concentration for boron for irrigation supply is 0.75 mg/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/15/2002-7/29/2002. Santa Lucia Coast is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 72740, Boron
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 9987
 
Pollutant: Boron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 52
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Coastal Confluences (CC) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 52 samples exceed the criterion for Boron, dissolved.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in Table 3.4 (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). Table 3-4 (page III-9) lists the maximum concentration for boron for irrigation supply is 0.75 mg/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 4/24/2001-12/20/2006. CCAMP Coastal confluence monitoring is conducted monthly (with the exception of April 2003 - December 2003) and is ongoing.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
 
DECISION ID
109286
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Chlorophyll-a
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: No new data were assessed for the 2020 listing cycle.

This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

Ten lines of evidence are available in the administrative record to assess this pollutant. Zero of the 134 samples exceed the evaluation guideline (North Carolina Administrative code, Title 15A) used to interpret the narrative water quality objective for bio-stimulation risk and aquatic life beneficial uses.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the 134 samples exceed the evaluation guideline and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: This is a decision previously approved by the State Water Resources Control Board and the USEPA. No new data were assessed by the Regional Board for the current cycle. The decision has not changed.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 109286, Chlorophyll-a
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 10017
 
Pollutant: Chlorophyll-a
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 57
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Coastal Confluences (CC) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 57 samples exceed the criterion for Chlorophyll a.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (general objective for biostimulatory substances, Water Quality Control Plan, Central Coast Basin, Chapter III, Section II).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
Objective/Criterion Reference: North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards
Objective/Criterion Reference: Water quality standards table
 
Evaluation Guideline: North Carolina Administrative code (NCAC), Title 15A - Environmental and Natural Resources, Subchapter 2B-Surface water and wetland standards, Rule 0211-Fresh surface water quality standards for class C waters (Class C is defined as freshwaters protected for secondary recreation, fishing, aquatic life including propagation and survival, and wildlife). Section 3(a) of Rule 0211 applies to all fresh surface waters and states that chlorophyll a is not to exceed 40 ug/L.
Guideline Reference: North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards
Guideline Reference: North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 4/24/2001-12/20/2006. CCAMP Coastal confluence monitoring is conducted monthly (with the exception of April 2003 - December 2003) and is ongoing.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109286, Chlorophyll-a
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 12751
 
Pollutant: Chlorophyll-a
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Diurnal Dissolved Oxygen Sampling (DO) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chlorophyll a.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (general objective for biostimulatory substances, Water Quality Control Plan, Central Coast Basin, Chapter III, Section II).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
Objective/Criterion Reference: North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards
Objective/Criterion Reference: Water quality standards table
 
Evaluation Guideline: North Carolina Administrative code (NCAC), Title 15A - Environmental and Natural Resources, Subchapter 2B-Surface water and wetland standards, Rule 0211-Fresh surface water quality standards for class C waters (Class C is defined as freshwaters protected for secondary recreation, fishing, aquatic life including propagation and survival, and wildlife). Section 3(a) of Rule 0211 applies to all fresh surface waters and states that chlorophyll a is not to exceed 40 ug/L.
Guideline Reference: North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards
Guideline Reference: North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 7/3/2001. Diurnal monitoring conducted in summer months at all CCAMP monitoring sites.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109286, Chlorophyll-a
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 10018
 
Pollutant: Chlorophyll-a
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 57
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Coastal Confluences (CC) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 57 samples exceed the criterion for Chlorophyll a.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (general objective for biostimulatory substances, Water Quality Control Plan, Central Coast Basin, Chapter III, Section II).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
Objective/Criterion Reference: North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards
Objective/Criterion Reference: Water quality standards table
 
Evaluation Guideline: North Carolina Administrative code (NCAC), Title 15A - Environmental and Natural Resources, Subchapter 2B-Surface water and wetland standards, Rule 0211-Fresh surface water quality standards for class C waters (Class C is defined as freshwaters protected for secondary recreation, fishing, aquatic life including propagation and survival, and wildlife). Section 3(a) of Rule 0211 applies to all fresh surface waters and states that chlorophyll a is not to exceed 40 ug/L.
Guideline Reference: North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards
Guideline Reference: North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 4/24/2001-12/20/2006. CCAMP Coastal confluence monitoring is conducted monthly (with the exception of April 2003 - December 2003) and is ongoing.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109286, Chlorophyll-a
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 52029
 
Pollutant: Chlorophyll-a
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 38
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 38 samples exceed the criterion for Chlorophyll a.
Data Reference: Coastal Confluences field data 2007-2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (general objective for biostimulatory substances, Water Quality Control Plan, Central Coast Basin, Chapter III, Section II).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline: North Carolina Administrative code (NCAC), Title 15A - Environmental and Natural Resources, Subchapter 2B-Surface water and wetland standards, Rule 0211-Fresh surface water quality standards for class C waters (Class C is defined as freshwaters protected for secondary recreation, fishing, aquatic life including propagation and survival, and wildlife). Section 3(a) of Rule 0211 applies to all fresh surface waters and states that chlorophyll a is not to exceed 40 ug/L.
Guideline Reference: North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards
Guideline Reference: North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards
Guideline Reference: Water quality standards table
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 1/18/2007-6/22/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109286, Chlorophyll-a
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 52044
 
Pollutant: Chlorophyll-a
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 23
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 23 samples exceed the criterion for Chlorophyll a.
Data Reference: Santa Lucia Watershed Rotation field data 2009
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (general objective for biostimulatory substances, Water Quality Control Plan, Central Coast Basin, Chapter III, Section II).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline: North Carolina Administrative code (NCAC), Title 15A - Environmental and Natural Resources, Subchapter 2B-Surface water and wetland standards, Rule 0211-Fresh surface water quality standards for class C waters (Class C is defined as freshwaters protected for secondary recreation, fishing, aquatic life including propagation and survival, and wildlife). Section 3(a) of Rule 0211 applies to all fresh surface waters and states that chlorophyll a is not to exceed 40 ug/L.
Guideline Reference: North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards
Guideline Reference: North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards
Guideline Reference: Water quality standards table
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 2 monitoring sites [ 310SLM-San Luis Obispo Creek at Mission Plaza, 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/21/2009-12/16/2009.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109286, Chlorophyll-a
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 52060
 
Pollutant: Chlorophyll-a
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 38
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 38 samples exceed the criterion for Chlorophyll a.
Data Reference: Coastal Confluences field data 2007-2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (general objective for biostimulatory substances, Water Quality Control Plan, Central Coast Basin, Chapter III, Section II).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline: North Carolina Administrative code (NCAC), Title 15A - Environmental and Natural Resources, Subchapter 2B-Surface water and wetland standards, Rule 0211-Fresh surface water quality standards for class C waters (Class C is defined as freshwaters protected for secondary recreation, fishing, aquatic life including propagation and survival, and wildlife). Section 3(a) of Rule 0211 applies to all fresh surface waters and states that chlorophyll a is not to exceed 40 ug/L.
Guideline Reference: North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards
Guideline Reference: North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards
Guideline Reference: Water quality standards table
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 1/18/2007-6/22/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109286, Chlorophyll-a
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 12737
 
Pollutant: Chlorophyll-a
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Diurnal Dissolved Oxygen Sampling (DO) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chlorophyll a.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (general objective for biostimulatory substances, Water Quality Control Plan, Central Coast Basin, Chapter III, Section II).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
Objective/Criterion Reference: North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards
Objective/Criterion Reference: Water quality standards table
 
Evaluation Guideline: North Carolina Administrative code (NCAC), Title 15A - Environmental and Natural Resources, Subchapter 2B-Surface water and wetland standards, Rule 0211-Fresh surface water quality standards for class C waters (Class C is defined as freshwaters protected for secondary recreation, fishing, aquatic life including propagation and survival, and wildlife). Section 3(a) of Rule 0211 applies to all fresh surface waters and states that chlorophyll a is not to exceed 40 ug/L.
Guideline Reference: North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards
Guideline Reference: North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected on a single day 7/3/2001. Diurnal monitoring conducted in summer months at all CCAMP monitoring sites.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109286, Chlorophyll-a
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 12574
 
Pollutant: Chlorophyll-a
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Santa Lucia (SantaLucia) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 15 samples exceed the criterion for Chlorophyll a.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (general objective for biostimulatory substances, Water Quality Control Plan, Central Coast Basin, Chapter III, Section II).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
Objective/Criterion Reference: North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards
Objective/Criterion Reference: Water quality standards table
 
Evaluation Guideline: North Carolina Administrative code (NCAC), Title 15A - Environmental and Natural Resources, Subchapter 2B-Surface water and wetland standards, Rule 0211-Fresh surface water quality standards for class C waters (Class C is defined as freshwaters protected for secondary recreation, fishing, aquatic life including propagation and survival, and wildlife). Section 3(a) of Rule 0211 applies to all fresh surface waters and states that chlorophyll a is not to exceed 40 ug/L.
Guideline Reference: North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards
Guideline Reference: North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/15/2002-3/19/2003. Santa Lucia Coast is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 109286, Chlorophyll-a
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51758
 
Pollutant: Chlorophyll-a
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 23
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 23 samples exceed the criterion for Chlorophyll a.
Data Reference: Santa Lucia Watershed Rotation field data 2009
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (general objective for biostimulatory substances, Water Quality Control Plan, Central Coast Basin, Chapter III, Section II).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline: North Carolina Administrative code (NCAC), Title 15A - Environmental and Natural Resources, Subchapter 2B-Surface water and wetland standards, Rule 0211-Fresh surface water quality standards for class C waters (Class C is defined as freshwaters protected for secondary recreation, fishing, aquatic life including propagation and survival, and wildlife). Section 3(a) of Rule 0211 applies to all fresh surface waters and states that chlorophyll a is not to exceed 40 ug/L.
Guideline Reference: North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards
Guideline Reference: North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards
Guideline Reference: Water quality standards table
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 2 monitoring sites [ 310SLM-San Luis Obispo Creek at Mission Plaza, 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/21/2009-12/16/2009.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 109286, Chlorophyll-a
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 12575
 
Pollutant: Chlorophyll-a
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Santa Lucia (SantaLucia) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 15 samples exceed the criterion for Chlorophyll a.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (general objective for biostimulatory substances, Water Quality Control Plan, Central Coast Basin, Chapter III, Section II).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
Objective/Criterion Reference: North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards
Objective/Criterion Reference: Water quality standards table
 
Evaluation Guideline: North Carolina Administrative code (NCAC), Title 15A - Environmental and Natural Resources, Subchapter 2B-Surface water and wetland standards, Rule 0211-Fresh surface water quality standards for class C waters (Class C is defined as freshwaters protected for secondary recreation, fishing, aquatic life including propagation and survival, and wildlife). Section 3(a) of Rule 0211 applies to all fresh surface waters and states that chlorophyll a is not to exceed 40 ug/L.
Guideline Reference: North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards
Guideline Reference: North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/15/2002-3/19/2003. Santa Lucia Coast is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
 
DECISION ID
85157
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Permethrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 at least one line of evidence is necessary to assess listing status, but under section 3.6 at least two lines of evidence are necessary to assess listing status and the pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the section 303(d) List.

Two lines of evidence are available in the administrative record to assess this pollutant. The single sediment sample did not exceed the evaluation guideline used to interpret the narrative water quality objective for aquatic life protection. This sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported using table 3.1. Therefore, the use support rating is set to 'insufficient information'.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. The single sample did not exceed the evaluation guideline and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 85157, Permethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57904
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Permethrin, total.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for permethrin is the median lethal concentration (LC50) of 8.9 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 8.9 ug/g is the geometric mean of LC50 values for permethrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 85157, Permethrin
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57910
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Permethrin, total.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coast Basin (CCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for permethrin is the median lethal concentration (LC50) of 8.9 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 8.9 ug/g is the geometric mean of LC50 values for permethrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ San Luis Obispo Creek at San Luis Bay Drive - 310SLBxxx]
Temporal Representation: Data was collected on a single day 6/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
 
DECISION ID
77845
Region 3     
San Luis Obispo Creek (below Osos Street)
 
Pollutant: Benthic Community Effects
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Sources: A Source Unknown
Expected TMDL Completion Date: 2027
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Benthic Community Effects is being considered for placement on the CWA section 303(d) List under sections 3.9 and 3.1 of the Listing Policy. Under section 3.9, an additional line of evidence associating Benthic Community Effects with a water or sediment concentration of pollutant(s) is necessary to assess listing status.

One line of evidence is available in the administrative record to assess this indicator and 14 supporting lines of evidence are available to show impacts to aquatic life uses. All three benthic invertebrate samples scored below 40 on the Sothern California IBI and are therefore is below the impairment threshold. This water body segment if also on the CWA Section 303(d) List for Nitrate and Low Dissolved Oxygen.

Based on the readily available data and information, the weight of evidence provides sufficient justification for placing Benthic Community Effects in this water segment on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies does not satisfy the data quantity requirements of section 3.9 of the Policy.
3. Pursuant to section 3.9 of the Listing Policy, the water exhibits significant degradation in biological populations and/or communities as compared to reference site(s) using the California Stream Condition Index and there are is supporting evidence showing pollutant concentrations impacting aquatic life uses in this water body segment. Therefore this water body segment meets the requirement of Section 3.9 of the listing policy for placement on the 303(d) List.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not being met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 77845, Benthic Community Effects
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 49223
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 115
Number of Exceedances: 81
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 81 of 115 samples exceed the criterion for Oxygen, Dissolved.
Data Reference: Nutrient Numeric Endpoint Study for San Luis Obispo Creek, July - August 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 5 monitoring sites [ RW_4- SLO Creek 75 meters upstream of City WWTP Outfall, RW_5- SLO Creek 50 meters downstream of City WWTP Outfall and Perfumo Creek, RW_8.2 - SLO Creek downstream of South Higuera St. Bridge, Station # 6 West of 101 Bridge, San_Luis_Bay_Drive_Bridge - San Luis Obispo Creek]
Temporal Representation: Data was collected over the time period 7/18/2010-8/16/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: There is no QAPP written specifically for this project. However, The City of San Luis Obispo Lab is certified by the State of California's Environmental Laboratory Accreditation Program (ELAP). In addition, calibration data for field probes was provided
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 77845, Benthic Community Effects
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51913
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 25
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 1 of 25 samples exceed the criterion for Oxygen, Dissolved.
Data Reference: Santa Lucia Watershed Rotation field data 2009
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 2 monitoring sites [ 310SLM-San Luis Obispo Creek at Mission Plaza, 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/21/2009-12/16/2009.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 77845, Benthic Community Effects
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 57819
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 3
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: All three of the IBI scores are 39 or below and are therefore are below the impairment threshold of the Southern California IBI. In 2007, a methods comparison study was conducted in this waterbody resulting in the collection of more than one sample at the San Luis Obispo Creek station and more than one IBI score was reported. These samples are not spatially or temporally independent as defined in the Listing Policy. For the purposes of this assessment, staff will use the IBI score from the 2007 sample that was collected following the SWAMP Reach Wide Benthos method, or RWB. The three RWB samples included in this assessment have the following IBI scores: The 2007 sample IBI score was 17, the 2009 sample IBI score was 14 and the 2010 sample IBI score was 29.
Data Reference: Coastal Confluences 2008 2009
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: The IBI is a multi-metric assessment that employs biological metrics that respond to a habitat or water quality impairment. Each of the biological metrics measured at a site are converted to an IBI score then summed. These cumulative scores are then ranked. For the Southern California IBI, sites with scores of 39 or less are considered to have impaired conditions.
Guideline Reference: A Quantitative Tool for Assessing the Integrity of Southern Coastal California Streams. Environmental Management. Volume 35, number 1 (2005): pp. 1-13
 
Spatial Representation: Surveys done at the following station: 310SLBxxx-San Luis Obispo Creek at San Luis Bay Drive.
Temporal Representation: Surveys done on April 12, 2007 and May 4, 2009.
Environmental Conditions:
QAPP Information: Data were collected following SWAMP QA Protocols for the Central Coast Ambient Monitoring Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 77845, Benthic Community Effects
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 48873
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 50
Number of Exceedances: 50
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 50 of 50 samples exceed the criterion for Nitrate as N.
Data Reference: Nutrient Numeric Endpoint Study for San Luis Obispo Creek, July - August 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Technical Approach to Develop Nutrient Numeric Endpoints for California. U.S. EPA Region IX. State Water Resources Control Board. 68-C-02-108-To-111
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 5 monitoring sites [ Station # 6 West of 101 Bridge, Station # 2 RW4:, Station # 4 RW5, Station # 5 RW 8.2, Station # 7 San Luis Bay Drive at Avila Beach Drive]
Temporal Representation: Data was collected over the time period 7/18/2010-8/16/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: There is no QAPP written specifically for this project. However, The City of SLO's Lab is certified with the Department of Public Health in accordance with the CWC section 13176. In addition QC data are provided with laboratory analyses and QC procedures
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 77845, Benthic Community Effects
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51759
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 40
Number of Exceedances: 40
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 40 of 40 samples exceed the criterion for Nitrate as N.
Data Reference: Coastal Confluences field data 2007-2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Technical Approach to Develop Nutrient Numeric Endpoints for California. U.S. EPA Region IX. State Water Resources Control Board. 68-C-02-108-To-111
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 1/18/2007-6/22/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 77845, Benthic Community Effects
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51760
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 25
Number of Exceedances: 13
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 13 of 25 samples exceed the criterion for Nitrate as N.
Data Reference: Santa Lucia Watershed Rotation field data 2009
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Technical Approach to Develop Nutrient Numeric Endpoints for California. U.S. EPA Region IX. State Water Resources Control Board. 68-C-02-108-To-111
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 2 monitoring sites [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road, 310SLM-San Luis Obispo Creek at Mission Plaza]
Temporal Representation: Data was collected over the time period 1/21/2009-12/16/2009.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 77845, Benthic Community Effects
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51968
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 25
Number of Exceedances: 11
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 11 of 25 samples exceed the criterion for Nitrate as N.
Data Reference: Santa Lucia Watershed Rotation field data 2009
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Maximum Contaminant Level for nitrate (NO3 as N) incorporated by reference in the Basin Plan is 10.0 mg/L (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 2 monitoring sites [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road, 310SLM-San Luis Obispo Creek at Mission Plaza]
Temporal Representation: Data was collected over the time period 1/21/2009-12/16/2009.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 77845, Benthic Community Effects
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51967
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 40
Number of Exceedances: 30
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 30 of 40 samples exceed the criterion for Nitrate as N.
Data Reference: Coastal Confluences field data 2007-2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Maximum Contaminant Level for nitrate (NO3 as N) incorporated by reference in the Basin Plan is 10.0 mg/L (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 1/18/2007-6/22/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 77845, Benthic Community Effects
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 10081
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 16
Number of Exceedances: 15
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Santa Lucia (SantaLucia) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 15 of 16 samples exceed the criterion for Nitrate as N.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin Objective for municipal and domestic supply uses of inland surface waters (Section II.A.2) states the following: waters shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Article 4, Chapter 15, Section 64435, Tables 2 and 3 as listed in Table 3-2. The maximum contaminant level listed in Table 3-2 (inorganic and fluoride concentrations not to be exceeded in domestic or municipal supply) for nitrate is 10.0 mg/L (NO3 as N).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
Objective/Criterion Reference: Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/15/2002-3/19/2003. Santa Lucia Coast is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 77845, Benthic Community Effects
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 48882
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 50
Number of Exceedances: 40
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 40 of 50 samples exceed the criterion for Nitrate as N.
Data Reference: Nutrient Numeric Endpoint Study for San Luis Obispo Creek, July - August 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Maximum Contaminant Level for nitrate (NO3 as N) incorporated by reference in the Basin Plan is 10.0 mg/L (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 5 monitoring sites [ Station # 6 West of 101 Bridge, Station # 2 RW4:, Station # 4 RW5, Station # 5 RW 8.2, Station # 7 San Luis Bay Drive at Avila Beach Drive]
Temporal Representation: Data was collected over the time period 7/18/2010-8/16/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: There is no QAPP written specifically for this project. However, The City of SLO's Lab is certified with the Department of Public Health in accordance with the CWC section 13176. In addition QC data are provided with laboratory analyses and QC procedures
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 77845, Benthic Community Effects
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 10003
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 59
Number of Exceedances: 41
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Coastal Confluences (CC) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 41 of 59 samples exceed the criterion for Nitrate as N.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin Objective for municipal and domestic supply uses of inland surface waters (Section II.A.2) states the following: waters shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Article 4, Chapter 15, Section 64435, Tables 2 and 3 as listed in Table 3-2. The maximum contaminant level listed in Table 3-2 (inorganic and fluoride concentrations not to be exceeded in domestic or municipal supply) for nitrate is 10.0 mg/L (NO3 as N).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
Objective/Criterion Reference: Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 4/24/2001-12/20/2006. CCAMP Coastal confluence monitoring is conducted monthly (with the exception of April 2003 - December 2003) and is ongoing.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 77845, Benthic Community Effects
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 51912
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 41
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for San Luis Obispo Creek (below Osos Street) to determine beneficial use support and results are as follows: 0 of 41 samples exceed the criterion for Oxygen, Dissolved.
Data Reference: Coastal Confluences field data 2007-2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Basin Plan).
Objective/Criterion Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (below Osos Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 1/18/2007-6/22/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 77845, Benthic Community Effects
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 12717
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 59
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Coastal Confluences (CC) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 1 of 59 samples exceed the criterion for Oxygen, Dissolved.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin, Cold Water Habitat Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive]
Temporal Representation: Data was collected over the time period 4/24/2001-12/20/2006. CCAMP Coastal confluence monitoring is conducted monthly (with the exception of April 2003 - December 2003) and is ongoing.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 77845, Benthic Community Effects
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 12752
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 13
Number of Exceedances: 7
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Diurnal Dissolved Oxygen Sampling (DO) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 7 of 13 samples exceed the criterion for Oxygen, Dissolved.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin, Cold Water Habitat Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 2 monitoring sites [ 310SLB-San Luis Obispo Creek at San Luis Bay Drive, 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 7/3/2001-8/7/2006. Diurnal monitoring conducted in summer months at all CCAMP monitoring sites.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 77845, Benthic Community Effects
Region 3     
San Luis Obispo Creek (below Osos Street)
 
LOE ID: 12576
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Santa Lucia (SantaLucia) data for San Luis Obispo Creek (Below W Marsh Street) to determine beneficial use support and results are as follows: 0 of 16 samples exceed the criterion for Oxygen, Dissolved.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin, Cold Water Habitat Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Obispo Creek (Below W Marsh Street) was collected at 1 monitoring site [ 310SLV-San Luis Obispo Creek at Los Osos Valley Road]
Temporal Representation: Data was collected over the time period 1/15/2002-3/19/2003. Santa Lucia Coast is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):