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

Supporting Information

Regional Board 9 - San Diego Region

Water Body Name: Mission Bay Shoreline, at Bonita Cove (eastern shore)
Water Body ID: CAC9075100020111101114700
Water Body Type: Coastal & Bay Shoreline
 
DECISION ID
82029
Region 9     
Mission Bay Shoreline, at Bonita Cove (eastern shore)
 
Pollutant: Indicator Bacteria
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: 2025
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.

Three lines of evidence are available in the administrative record to assess this pollutant. In LOE 74334, twenty-nine of the 204 samples exceed the Water Quality Objective for enterococci of a geomean of 35 /100 ml.

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.Twenty-nine of 204 samples exceed the Water Quality Objective for enterococci of a geomean of 35 /100 ml and this exceeds the allowable frequency for the AB411 period referred to in Session 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: 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 82029, Indicator Bacteria
Region 9     
Mission Bay Shoreline, at Bonita Cove (eastern shore)
 
LOE ID: 74336
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 204
Number of Exceedances: 3
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Three of the 204 geomeans exceeded the objective. The samples were collected during dry weather from April through October only. According to the listing Policy section 3.3 a four percent exceedance frequency should be used.
Data Reference: Data for Region 9 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 Bonita Cove eastern shore site.
Temporal Representation: Samples were collected approximately once a week from May 3, 2005 to August 31, 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 82029, Indicator Bacteria
Region 9     
Mission Bay Shoreline, at Bonita Cove (eastern shore)
 
LOE ID: 74335
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 204
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Zero of the 204 geomeans exceeded the objective. The samples were collected during dry weather from April through October only. According to the listing Policy section 3.3 a four percent exceedance frequency should be used.
Data Reference: Data for Region 9 Beach Watch.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The standard for fecal coliform states that the 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 Bonita Cove eastern shore site.
Temporal Representation: Samples were collected approximately once a week from May 3, 2005 to August 31, 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 82029, Indicator Bacteria
Region 9     
Mission Bay Shoreline, at Bonita Cove (eastern shore)
 
LOE ID: 74334
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 204
Number of Exceedances: 29
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Twenty-nine of the 204 geomeans exceeded the objective. The samples were collected during dry weather from April through October only. According to the listing Policy section 3.3 a four percent exceedance frequency should be used.
Data Reference: Data for Region 9 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 Bonita Cove eastern shore site.
Temporal Representation: Samples were collected approximately once a week from May 3, 2005 to August 31, 2010.
Environmental Conditions:
QAPP Information: The samples were collected for the Beach Watch program.
QAPP Information Reference(s):