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

Supporting Information

Regional Board 1 - North Coast Region

Water Body Name:	Manchester State Beach
Water Body ID:	CAC1136301120120426085558
Water Body Type:	Coastal & Bay Shoreline


DECISION ID	78068	Region 1
Manchester State Beach

Pollutant:	Indicator Bacteria
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:	Fecal indicator bacteria (which includes enterococcus, fecal coliform and total coliform) are being considered for placement on the Section 303(d) list under Section 3.3 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess indicator bacteria and contact recreation: one for enterococcus and one for fecal coliform. In addition, One LOE for the assessment of total coliform as it applies to the shellfish harvesting beneficial use. It should be noted that an additional LOE for total coliform data was not utilized in this decision because these bacteria are widespread in nature and occur in non-fecal sources such as soil and submerged wood and are not a good measure for the protection of contact recreation beneficial uses. However, the California Ocean Plan has specific total coliform objectives for waters designated for shellfish harvesting (SHELL). One of one sample exceeded the single sample SHELL objective of 230 MPN/100mL. Data assessed for the 2012 Integrated Report include ocean beach bacteria data collected by the Mendocino County Environmental Health Division in accordance with AB411 (Chapter 765, Statutes of 1997) requirements. In accordance with Section 3.3 of the Listing Policy, a 4% exceedance rate shall be used to add waters to the List "if water quality monitoring was conducted April 1 through October 31 only". However, the data assessed in this decision include data collected during months outside the April - October range. Therefore, this pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy, using a 10% exceedance rate. Additionally, there must be a minimum of either (a) 26 samples, or (b) greater than or equal to 5 exceedances of the objective with less than 26 samples in order to determine with the power and confidence of the Listing Policy if standards are not met under Section 3.2 of the Listing Policy. Although there are not enough samples to make a listing determination, it can be noted that none of the enterococcus or fecal coliform single samples exceed the objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against adding this water segment-pollutant combination to the Section 303(d) list (i.e., sufficient justification to not list). This conclusion is based on the staff findings that: (1) The data used satisfy the data quality requirements of Section 6.1.4 of the Policy. (2) The data used satisfy the data quantity requirements of Section 6.1.5 of the Policy. (3) None of the 1 enterococcus, 1 fecal coliform or 1 total coliform samples exceed the water quality objectives, however this sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met per Section 3.3 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 region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

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 78068, Indicator Bacteria	Region 1
Manchester State Beach

LOE ID:

44703

Pollutant:

Total Coliform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

0 of 1 samples exceed the criterion forTotal Coliform.

Data Reference:

Data for Region 1 Beach Watch.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

California Ocean Plan (2009) single sample maximum states that total coliform density shall not exceed 10,000 MPN/100 mL

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 Manchester State Beach was collected at 1 monitoring site [ Manchester SB]

Temporal Representation:

Data was collected on a single day 5/5/2009.

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):

Line of Evidence (LOE) for Decision ID 78068, Indicator Bacteria	Region 1
Manchester State Beach

LOE ID:

44625

Pollutant:

Fecal Coliform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

0 of 1 samples exceed the criterion for Fecal Coliform.

Data Reference:

Data for Region 1 Beach Watch.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

California Ocean Plan (SWRCB 2009) states that the single sample maximum for fecal coliform shall not exceed 400 MPN/100 mL

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 Manchester State Beach was collected at 1 monitoring site [ Manchester SB]

Temporal Representation:

Data was collected on a single day 5/5/2009.

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):

Line of Evidence (LOE) for Decision ID 78068, Indicator Bacteria	Region 1
Manchester State Beach

LOE ID:

44434

Pollutant:

Enterococcus

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

0 of 1 samples exceed the criterion for Enterococci.

Data Reference:

Data for Region 1 Beach Watch.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

California Ocean Plan (SWRCB 2009) states that the single sample maximum for Enterococcus shall not exceed 104 MPN/100 mL.

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 Manchester State Beach was collected at 1 monitoring site [ Manchester SB]

Temporal Representation:

Data was collected on a single day 5/5/2009.

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):

Line of Evidence (LOE) for Decision ID 78068, Indicator Bacteria	Region 1
Manchester State Beach

LOE ID:

47617

Pollutant:

Total Coliform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Shellfish Harvesting

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

1 of 1 samples exceed the objective of 230 MPN/100mL applied as a single sample maximum for Total Coliform.

Data Reference:

Data for Region 1 Beach Watch.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Ocean Plan 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 Manchester State Beach was collected at 1 monitoring site [Manchester SB]

Temporal Representation:

Data was collected on a single day 5/5/2009.

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):