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

Supporting Information

Regional Board 3 - Central Coast Region

Water Body Name: Pacific Ocean at Main Beach (Santa Cruz County), at San Lorenzo River mouth
Water Body ID: CAC3041205320100414194432
Water Body Type: Coastal & Bay Shoreline
 
DECISION ID
72345
Region 3     
Pacific Ocean at Main Beach (Santa Cruz County), at San Lorenzo River mouth
 
Pollutant: Enterococcus
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 3.2 and 3.3 of the Listing Policy. Under these sections, 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. Twelve of 175 samples exceeded the geometric mean standard for enterococcus (LOEs 19589 and 56371) and 12 of 276 samples exceeded the single sample maximum for enterococcus (LOEs 19590 and 56370) for the water contact recreation water quality standard (Water Quality Control Plan: Ocean Waters of California, SWRCB, 2005).

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. Twelve of 175 samples exceeded the geometric mean standard for enterococcus (LOEs 19589 and 56371) and 12 of 276 samples exceeded the single sample maximum for enterococcus (LOEs 19590 and 56370) for the water contact recreation water quality standard 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 72345, Enterococcus
Region 3     
Pacific Ocean at Main Beach (Santa Cruz County), at San Lorenzo River mouth
 
LOE ID: 56370
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 163
Number of Exceedances: 6
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Beach Watch Program data that is collected by each County's Environmental Health Department for Pacific Ocean at Main Beach (Santa Cruz County), at San Lorenzo River mouth to determine beneficial use support and results are as follows: 6 of 163 samples exceed the criterion for Enterococci.
Data Reference: Data for Region 3 Beach Watch.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Ocean Plan (SWRCB 2005) single sample maximum for enterococcus density shall not exceed 104 per 100 mL.
Objective/Criterion Reference: Water Quality Control Plan Ocean Waters of California. California Ocean Plan 2005. Sacramento, CA: State Water Resources Control Board, California Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Pacific Ocean at Main Beach (Santa Cruz County), at San Lorenzo River mouth was collected at 1 monitoring site [ Main Beach @ San Lorenzo River]
Temporal Representation: Data was collected over the time period 1/3/2007-8/23/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Water Board staff assessed Beach Watch Program data that is collected by each County's Environmental Health Department. There is no QA Project Plan but instead each County follows their own Quality Assurance Procedures
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 72345, Enterococcus
Region 3     
Pacific Ocean at Main Beach (Santa Cruz County), at San Lorenzo River mouth
 
LOE ID: 19590
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 113
Number of Exceedances: 6
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed data for Pacific Ocean at Main Beach (Santa Cruz County), at San Lorenzo River mouth to determine beneficial use support and results are as follows: 6 of 113 samples exceed the criterion for Enterococci.
Data Reference: AB 411 Data for 2004
  AB 411 Data for 2005
  AB 411 Data for 2006
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Ocean Plan (SWRCB 2005) states that the single sample maximum for Enterococcus shall not exceed 104 MPN/100 mL.
Objective/Criterion Reference: Water Quality Control Plan Ocean Waters of California. California Ocean Plan 2005. Sacramento, CA: State Water Resources Control Board, California Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Pacific Ocean at Main Beach was collected at one AB411 monitoring site (Main Beach @ San Lorenzo River)
Temporal Representation: Data was collected over the time period 3/8/2004 - 12/26/2006. This includes weekly AB411 monitoring between April 1 and October 31 of each year.
Environmental Conditions:
QAPP Information: QA information not available
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 72345, Enterococcus
Region 3     
Pacific Ocean at Main Beach (Santa Cruz County), at San Lorenzo River mouth
 
LOE ID: 19589
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 26
Number of Exceedances: 4
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed data for Pacific Ocean at Main Beach (Santa Cruz County), at San Lorenzo River mouth to determine beneficial use support and results are as follows: 4 of 26 samples exceed the criterion for Enterococci.
Data Reference: AB 411 Data for 2004
  AB 411 Data for 2005
  AB 411 Data for 2006
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Ocean Plan (SWRCB 2005) states that the geometric mean for Enterococcus shall not exceed 35 MPN/100 mL.
Objective/Criterion Reference: Water Quality Control Plan Ocean Waters of California. California Ocean Plan 2005. Sacramento, CA: State Water Resources Control Board, California Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Pacific Ocean at Main Beach was collected at one AB411 monitoring site (Main Beach @ San Lorenzo River)
Temporal Representation: Data was collected over the time period 3/8/2004 - 12/26/2006. This includes weekly AB411 monitoring between April 1 and October 31 of each year.
Environmental Conditions:
QAPP Information: QA information not available
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 72345, Enterococcus
Region 3     
Pacific Ocean at Main Beach (Santa Cruz County), at San Lorenzo River mouth
 
LOE ID: 56371
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 149
Number of Exceedances: 8
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Eight of the 149 geomeans exceeded the entercoccus objective.
Data Reference: Data for Region 3 Beach Watch.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The geometric mean standard for enterococcus states that the entercoccus density shall not exceed 35 per 100 mL. Water Quality Control Plan for Ocean Waters 2009.
Objective/Criterion Reference: California Ocean Plan Water Quality Control Plan Ocean Waters of California 2009
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from station 269 Main Beach at San Lorenzo River.
Temporal Representation: Samples were collected approximately once a week from 2007 to 2010.
Environmental Conditions:
QAPP Information: The samples were collected for the Beach Watch program.
QAPP Information Reference(s):
 
 
DECISION ID
72505
Region 3     
Pacific Ocean at Main Beach (Santa Cruz County), at San Lorenzo River mouth
 
Pollutant: Fecal Coliform
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 3.2 and 3.3 of the Listing Policy. Under these sections, 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. Two of 174 samples exceeded the geometric mean standard for fecal coliform (LOEs 19568 and 56390) and 10 of 260 samples exceeded the single sample maximum for fecal coliform (LOEs 19569 and 56372) for the water contact recreation water quality standard (Water Quality Control Plan: Ocean Waters of California, SWRCB, 2005).

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. Two of 174 samples exceeded the geometric mean standard for fecal coliform (LOEs 19568 and 56390) and 10 of 260 samples exceeded the single sample maximum for fecal coliform (LOEs 19569 and 56372) for the water contact recreation water quality standard 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 72505, Fecal Coliform
Region 3     
Pacific Ocean at Main Beach (Santa Cruz County), at San Lorenzo River mouth
 
LOE ID: 19568
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 23
Number of Exceedances: 2
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed data for Pacific Ocean at Main Beach (Santa Cruz County), at San Lorenzo River mouth to determine beneficial use support and results are as follows: 2 of 23 samples exceed the criterion for Coliform, Fecal.
Data Reference: AB 411 Data for 2004
  AB 411 Data for 2005
  AB 411 Data for 2006
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Ocean Plan (SWRCB 2005) states that the 30-day geometric mean for fecal coliform shall not exceed 200 MPN/100 mL.
Objective/Criterion Reference: Water Quality Control Plan Ocean Waters of California. California Ocean Plan 2005. Sacramento, CA: State Water Resources Control Board, California Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Pacific Ocean at Main Beach was collected at one AB411 monitoring site (Main Beach @ San Lorenzo River)
Temporal Representation: Data was collected over the time period 3/8/2004 - 12/26/2006. This includes weekly AB411 monitoring between April 1 and October 31 of each year.
Environmental Conditions:
QAPP Information: QA information not available
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 72505, Fecal Coliform
Region 3     
Pacific Ocean at Main Beach (Santa Cruz County), at San Lorenzo River mouth
 
LOE ID: 19569
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 94
Number of Exceedances: 3
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed data for Pacific Ocean at Main Beach (Santa Cruz County), at San Lorenzo River mouth to determine beneficial use support and results are as follows: 3 of 94 samples exceed the criterion for Coliform, Fecal.
Data Reference: AB 411 Data for 2004
  AB 411 Data for 2005
  AB 411 Data for 2006
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Ocean Plan (SWRCB 2005) states that the single sample maximum for fecal coliform shall not exceed 400 MPN/100 mL.
Objective/Criterion Reference: Water Quality Control Plan Ocean Waters of California. California Ocean Plan 2005. Sacramento, CA: State Water Resources Control Board, California Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Pacific Ocean at Main Beach was collected at one AB411 monitoring site (Main Beach @ San Lorenzo River)
Temporal Representation: Data was collected over the time period 3/8/2004 - 12/26/2006. This includes weekly AB411 monitoring between April 1 and October 31 of each year.
Environmental Conditions:
QAPP Information: QA information not available
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 72505, Fecal Coliform
Region 3     
Pacific Ocean at Main Beach (Santa Cruz County), at San Lorenzo River mouth
 
LOE ID: 56372
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 166
Number of Exceedances: 7
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Beach Watch Program data that is collected by each County's Environmental Health Department. E. coli data results are assessed using the Ocean Plan single sample maximum objective for fecal coliform to determine beneficial use support for the station named Pacific Ocean at Main Beach (Santa Cruz County), at San Lorenzo River mouth and results are as follows: 7 of 166 samples exceed the criterion for Coliform, Fecal.
Data Reference: Data for Region 3 Beach Watch.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Ocean Plan (SWRCB 2005) single sample maximum for fecal coliform density shall not exceed 400 per 100ml
Objective/Criterion Reference: Water Quality Control Plan Ocean Waters of California. California Ocean Plan 2005. Sacramento, CA: State Water Resources Control Board, California Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Pacific Ocean at Main Beach (Santa Cruz County), at San Lorenzo River mouth was collected at 1 monitoring site [ Main Beach @ San Lorenzo River]
Temporal Representation: Data was collected over the time period 1/3/2007-8/23/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Water Board staff assessed Beach Watch Program data that is collected by each County's Environmental Health Department. There is no QA Project Plan but instead each County follows their own Quality Assurance Procedures
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 72505, Fecal Coliform
Region 3     
Pacific Ocean at Main Beach (Santa Cruz County), at San Lorenzo River mouth
 
LOE ID: 56390
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 151
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: E. coli data results are assessed using the Ocean Plan objective for fecal coliform. A thirty day, rolling geomean was calculated for all data provided when four or more samples were collected within the 30 day period. 0 of the 151 geomeans exceeded the objective.
Data Reference: Data for Region 3 Beach Watch.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The geometric mean standard for fecal coliform states that the fecal coliform density shall not exceed 200 per 100 mL. Water Quality Control Plan for Ocean Waters 2009.
Objective/Criterion Reference: California Ocean Plan Water Quality Control Plan Ocean Waters of California 2009
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from station 269 Main Beach at San Lorenzo River.
Temporal Representation: Samples were collected approximately once a week from 2007 to 2010.
Environmental Conditions:
QAPP Information: The samples were collected for the Beach Watch program.
QAPP Information Reference(s):
 
 
DECISION ID
80774
Region 3     
Pacific Ocean at Main Beach (Santa Cruz County), at San Lorenzo River mouth
 
Pollutant: Total Coliform
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: This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.2 and 3.3 of the Listing Policy. Under these sections, 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. Seventy two of 164 samples (LOE 56391) exceeded the shellfish harvesting water quality objective (Water Quality Control Plan: Ocean Waters of California, SWRCB, 2009).

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 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. Seventy two of 164 samples (LOE 56391) exceeded the shellfish harvesting water quality objective and this exceeds 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 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 80774, Total Coliform
Region 3     
Pacific Ocean at Main Beach (Santa Cruz County), at San Lorenzo River mouth
 
LOE ID: 56391
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Shellfish Harvesting
 
Number of Samples: 164
Number of Exceedances: 72
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Beach Watch data for Pacific Ocean at Main Beach (Santa Cruz County), at San Lorenzo River mouth to determine beneficial use support and results are as follows: 72 of 164 samples exceed the criterion for Coliform, Total.
Data Reference: Data for Region 3 Beach Watch.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Ocean Plan (2009) states the following: At all areas where shellfish may be harvested for human consumption, the following bacterial objectives shall be maintained throughout the water column: Ten percent of the samples collected during any 30-day period shall not exceed 230 MPN/100mL.
Objective/Criterion Reference: California Ocean Plan Water Quality Control Plan Ocean Waters of California 2009
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Pacific Ocean at Main Beach (Santa Cruz County), at San Lorenzo River mouth was collected at 1 monitoring site [ Main Beach @ San Lorenzo River]
Temporal Representation: Data was collected over the time period 1/3/2007-8/23/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The samples were collected for the Beach Watch program.
QAPP Information Reference(s):