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

Supporting Information

Regional Board 2 - San Francisco Bay Region

Water Body Name: Pacific Ocean at Stinson Beach
Water Body ID: CAC2013001220110712220836
Water Body Type: Coastal & Bay Shoreline
 
DECISION ID
100097
Region 2     
Pacific Ocean at Stinson 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: 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.

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

Nine of the 499 samples exceed the OBJECTIVE for single sample maximum for Enterococcus.
Zero of the 400 samples exceed the OBJECTIVE for the geometric mean for Enterococcus.
One of the 499 samples exceed the OBJECTIVE for single sample maximum for Fecal Coliform.
Zero of the 400 samples exceed the OBJECTIVE for the geometric mean for Fecal Coliform.
Zero of the 499 samples exceed the OBJECTIVE for single sample maximum for Total Coliform.
Zero of the 400 samples exceed the OBJECTIVE for the geometric mean for Total Coliform.

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. Nine of the 499 samples exceed the OBJECTIVE for single sample maximum for Enterococcus. Zero of the 400 samples exceed the OBJECTIVE for the geometric mean for Enterococcus. One of the 499 samples exceed the OBJECTIVE for single sample maximum for Fecal Coliform. Zero of the 400 samples exceed the OBJECTIVE for the geometric mean for Fecal Coliform. Zero of the 499 samples exceed the OBJECTIVE for single sample maximum for Total Coliform. Zero of the 400 samples exceed the OBJECTIVE for the geometric mean for Total Coliform. These do 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 100097, Indicator Bacteria
Region 2     
Pacific Ocean at Stinson Beach
 
LOE ID: 90653
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 131
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Zero of the 131 geomeans exceeded the objective.
Data Reference: Data for Region 2 Beach Watch.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The geometric mean standard for entercoccus 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 at the North Stinson Beach site.
Temporal Representation: Samples were collected from April 2005 to August 2010.
Environmental Conditions:
QAPP Information: The samples were collected for the Beach Watch program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 100097, Indicator Bacteria
Region 2     
Pacific Ocean at Stinson Beach
 
LOE ID: 90648
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 135
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Zero of the 135 geomeans exceeded the objective.
Data Reference: Data for Region 2 Beach Watch.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The geometric mean standard for entercoccus 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 at the Central Stinson Beach site.
Temporal Representation: Samples were collected from April 2005 to August 2010.
Environmental Conditions:
QAPP Information: The samples were collected for the Beach Watch program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 100097, Indicator Bacteria
Region 2     
Pacific Ocean at Stinson Beach
 
LOE ID: 90905
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 499
Number of Exceedances: 9
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BeachWatch data for Pacific Ocean at Stinson Beach to determine beneficial use support and results are as follows: 9 of 499 samples exceed the criterion for Enterococci.
Data Reference: Data for Region 2 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 Pacific Ocean at Stinson Beach was collected at 3 monitoring sites [ Stinson Beach - Central, Stinson Beach - North, Stinson Beach South]
Temporal Representation: Data was collected over the time period 4/7/2005-8/25/2010.
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):
 
Line of Evidence (LOE) for Decision ID 100097, Indicator Bacteria
Region 2     
Pacific Ocean at Stinson Beach
 
LOE ID: 90814
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 499
Number of Exceedances: 1
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BeachWatch data for Pacific Ocean at Stinson Beach to determine beneficial use support and results are as follows: 1 of 499 samples exceed the criterion for Coliform, Fecal.
Data Reference: Data for Region 2 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 Pacific Ocean at Stinson Beach was collected at 3 monitoring sites [ Stinson Beach - Central, Stinson Beach - North, Stinson Beach South]
Temporal Representation: Data was collected over the time period 4/7/2005-8/25/2010.
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):
 
Line of Evidence (LOE) for Decision ID 100097, Indicator Bacteria
Region 2     
Pacific Ocean at Stinson Beach
 
LOE ID: 90650
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 135
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Zero of the 135 geomeans exceeded the objective.
Data Reference: Data for Region 2 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 at the Central Stinson Beach site.
Temporal Representation: Samples were collected from April 2005 to August 2010.
Environmental Conditions:
QAPP Information: The samples were collected for the beach watch program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 100097, Indicator Bacteria
Region 2     
Pacific Ocean at Stinson Beach
 
LOE ID: 90651
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 131
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Zero of the 131 geomeans exceeded the objective.
Data Reference: Data for Region 2 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 at the North Stinson Beach site.
Temporal Representation: Samples were collected from April 2005 to August 2010.
Environmental Conditions:
QAPP Information: The samples were collected for the beach watch program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 100097, Indicator Bacteria
Region 2     
Pacific Ocean at Stinson Beach
 
LOE ID: 90652
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 131
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Zero of the 131 geomeans exceeded the objective.
Data Reference: Data for Region 2 Beach Watch.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The geometric mean standard for total coliform states that the coliform density shall not exceed 1000 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 at the North Stinson Beach site.
Temporal Representation: Samples were collected from April 2005 to August 2010.
Environmental Conditions:
QAPP Information: The samples were collected for the Beach Watch program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 100097, Indicator Bacteria
Region 2     
Pacific Ocean at Stinson Beach
 
LOE ID: 90649
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 135
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Zero of the 135 geomeans exceeded the objective.
Data Reference: Data for Region 2 Beach Watch.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The geometric mean standard for total coliform states that the coliform density shall not exceed 1000 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 at the Central Stinson Beach site.
Temporal Representation: Samples were collected from April 2005 to August 2010.
Environmental Conditions:
QAPP Information: The samples were collected for the Beach Watch program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 100097, Indicator Bacteria
Region 2     
Pacific Ocean at Stinson Beach
 
LOE ID: 90655
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 134
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Zero of the 134 geomeans exceeded the objective.
Data Reference: Data for Region 2 Beach Watch.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The geometric mean standard for total coliform states that the coliform density shall not exceed 1000 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 at the South Stinson Beach site.
Temporal Representation: Samples were collected from April 2005 to August 2010.
Environmental Conditions:
QAPP Information: The samples were collected for the Beach Watch program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 100097, Indicator Bacteria
Region 2     
Pacific Ocean at Stinson Beach
 
LOE ID: 90861
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 499
Number of Exceedances: 0
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BeachWatch data for Pacific Ocean at Stinson Beach to determine beneficial use support and results are as follows: 0 of 499 samples exceed the criterion for Coliform, Total.
Data Reference: Data for Region 2 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 Pacific Ocean at Stinson Beach was collected at 3 monitoring sites [ Stinson Beach - Central, Stinson Beach - North, Stinson Beach South]
Temporal Representation: Data was collected over the time period 4/7/2005-8/25/2010.
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):
 
Line of Evidence (LOE) for Decision ID 100097, Indicator Bacteria
Region 2     
Pacific Ocean at Stinson Beach
 
LOE ID: 90656
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 134
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Zero of the 134 geomeans exceeded the objective.
Data Reference: Data for Region 2 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 at the South Stinson Beach site.
Temporal Representation: Samples were collected from April 2005 to August 2010.
Environmental Conditions:
QAPP Information: The samples were collected for the beach watch program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 100097, Indicator Bacteria
Region 2     
Pacific Ocean at Stinson Beach
 
LOE ID: 90654
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 134
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Zero of the 134 geomeans exceeded the objective.
Data Reference: Data for Region 2 Beach Watch.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The geometric mean standard for entercoccus 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 at the South Stinson Beach site.
Temporal Representation: Samples were collected from April 2005 to August 2010.
Environmental Conditions:
QAPP Information: The samples were collected for the Beach Watch program.
QAPP Information Reference(s):