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 Balboa Court
Water Body ID: CAC9075100020090422200349
Water Body Type: Coastal & Bay Shoreline
 
DECISION ID
127892
Region 9     
Mission Bay Shoreline, at Balboa Court
 
Pollutant: Indicator Bacteria
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: Applicable WQS attained; due to change in WQS
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.

One line of evidence is available in the administrative record to assess this pollutant. Zero of the five samples exceed the GM threshold for Enterococci.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for this water segment-pollutant combination to remain delisted 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. Zero of five samples exceeded the Enterococci water quality threshold for the protection of REC-1, and this is insufficient information for AB411 beaches listed in 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.

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 greater than 1 part per thousand more than 5 percent of the time, the enterococci bacteria objective applies. Therefore, this waterbody is being considered for placement on or removal from the CWA section 303(d) List under section 3.3 or 4.3 of the Listing Policy, as applicable, using the enterococci objective.

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. Indicator bacteria (total coliform, fecal coliform, E. coli, enterococci) populations may fluctuate substantially on a daily, seasonal, or yearly basis. Lacking constant inputs, they do not persist in the environment for a long period and effects are of relatively short duration. As a result, the historic levels of indicator bacteria 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 bacteria. Unrepresentative data may result in incorrectly placing or not placing a water body segment on the 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.

For enterococci data, Listing Policy sections 3.3 and 4.3 instructs to use the binomial distribution table in sections 3.2 and 4.2, as applicable. To use the binomial table that uses a four percent exceedance frequency, the data must be collected from coastal beaches or inland surface waters from April 1 through October 31 only, and where collected from inland waters from April 1 through October 31 only, bacterial measurements must be indicative of human fecal matter, and there is substantial human contact in the waterbody.

No fecal coliform data are used in this assessment because the fecal coliform water quality objective was superseded and is no longer used as the basis of any 303(d) List decision for water contact recreation.
 
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.
 
State Board Review of Regional Board Conclusion and Recommendation: 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 greater than 1 part per thousand more than 5 percent of the time, the enterococci bacteria objective applies. Therefore, this waterbody is being considered for placement on or removal from the CWA section 303(d) List under section 3.3 or 4.3 of the Listing Policy, as applicable, using the enterococci objective.

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. Indicator bacteria (total coliform, fecal coliform, E. coli, enterococci) populations may fluctuate substantially on a daily, seasonal, or yearly basis. Lacking constant inputs, they do not persist in the environment for a long period and effects are of relatively short duration. As a result, the historic levels of indicator bacteria 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 bacteria. Unrepresentative data may result in incorrectly placing or not placing a water body segment on the 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.

For enterococci data, Listing Policy sections 3.3 and 4.3 instructs to use the binomial distribution table in sections 3.2 and 4.2, as applicable. To use the binomial table that uses a four percent exceedance frequency, the data must be collected from coastal beaches or inland surface waters from April 1 through October 31 only, and where collected from inland waters from April 1 through October 31 only, bacterial measurements must be indicative of human fecal matter, and there is substantial human contact in the waterbody.

No fecal coliform data are used in this assessment because the fecal coliform water quality objective was superseded and is no longer used as the basis of any 303(d) List decision for water contact recreation.
 
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 127892, Indicator Bacteria
Region 9     
Mission Bay Shoreline, at Balboa Court
 
LOE ID: 30544
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 190
Number of Exceedances: 9
 
Data and Information Type: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: Beach monitoring data June 2001 through December 2007. A total of 191 single samples were collected of which 190 are dry weather (AB411) samples with nine samples exceeding the single sample water quality objective.
Data Reference: Department of Environmental Health, Ocean & Bay Recreational Water Quality Program, 2007. AB 411 monitoring data 1999 to 2007
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Geomean: Enterococcus density shall not exceed 35 per 100 ml.

Single Sample Maximum: Enterococcus density shall not exceed 104 per 100 ml (SWRCB, 2005).
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: Samples were collected from Balboa Court, San Diego, California. Station identification number is MB-225.
Temporal Representation: Samples were collected from June 2001 through December 2007.
Environmental Conditions:
QAPP Information: Quality control for the bacteria analysis portion was conducted in accordance with the County of San Diego, Department Public Health Laboratory Quality Assurance Manual.
QAPP Information Reference(s): County of San Diego, 2006. Department Public Health Laboratory, Quality Assurance Manual, December 2006
 
Line of Evidence (LOE) for Decision ID 127892, Indicator Bacteria
Region 9     
Mission Bay Shoreline, at Balboa Court
 
LOE ID: 28609
 
Pollutant: Enterococcus
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: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: Beach monitoring data was collected by the County of San Diego from June 2001 through December 2007. A total of 191 single samples were collected with one sample correlated with a storm event. The one sample did not exceed the water quality objective. This information will not be used in determining a listing decision, but is of interest to the Regional Board and has been included here as additional anecdotal information.
Data Reference: National Weather Service Forecast Office, San Diego, California, Chronological Regional Temperature and Precipitation Listings by Station
  Department of Environmental Health, Ocean & Bay Recreational Water Quality Program, 2007. AB 411 monitoring data 1999 to 2007
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Geomean: Enterococcus density shall not exceed 35 per 100 ml.

Single Sample Maximum: Enterococcus density shall not exceed 104 per 100 ml (SWRCB, 2005).
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: Samples were collected from Balboa Court, San Diego, California. Station identification number is MB-225.
Temporal Representation: Samples were collected from June 2001 through December 2007.
Environmental Conditions: Comparisons were made for all data and data associated with storm events. A storm event was defined as 0.2 inches of rainfall within a 72 hour period.

Analyzing only storm water bacteria data is important because the majority of beach monitoring data covers the months of April through October. The data may not capture the full impacts of seasonal storm events and high bacteria levels due to storm water runoff because much of the wet season for Southern California occurs in November through March
QAPP Information: Quality control for the bacteria analysis portion was conducted in accordance with the County of San Diego, Department Public Health Laboratory Quality Assurance Manual.
QAPP Information Reference(s): County of San Diego, 2006. Department Public Health Laboratory, Quality Assurance Manual, December 2006
 
Line of Evidence (LOE) for Decision ID 127892, Indicator Bacteria
Region 9     
Mission Bay Shoreline, at Balboa Court
 
LOE ID: 28612
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 45
Number of Exceedances: 0
 
Data and Information Type: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: Beach monitoring data was collected by the County of San Diego from June 2001 through December 2007. A total of 191 single samples were collected with 45 monthly geomeans calculated. None of the 45 geomeans exceeded the geomean water quality objective.
Data Reference: Department of Environmental Health, Ocean & Bay Recreational Water Quality Program, 2007. AB 411 monitoring data 1999 to 2007
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Geomean: Enterococcus density shall not exceed 35 per 100 ml.

Single Sample Maximum: Enterococcus density shall not exceed 104 per 100 ml (SWRCB, 2005).
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: Samples were collected from Balboa Court, San Diego, California. Station identification number is MB-225.
Temporal Representation: Samples were collected from June 2001 through December 2007.
Environmental Conditions:
QAPP Information: Quality control for the bacteria analysis portion was conducted in accordance with the County of San Diego, Department Public Health Laboratory Quality Assurance Manual.
QAPP Information Reference(s): County of San Diego, 2006. Department Public Health Laboratory, Quality Assurance Manual, December 2006
 
Line of Evidence (LOE) for Decision ID 127892, Indicator Bacteria
Region 9     
Mission Bay Shoreline, at Balboa Court
 
LOE ID: 28608
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 191
Number of Exceedances: 9
 
Data and Information Type: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: Beach monitoring data June 2001 through December 2007. A total of 191 single samples were collected with nine samples exceeding the single sample water quality objective.
Data Reference: Department of Environmental Health, Ocean & Bay Recreational Water Quality Program, 2007. AB 411 monitoring data 1999 to 2007
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Geomean: Enterococcus density shall not exceed 35 per 100 ml.

Single Sample Maximum: Enterococcus density shall not exceed 104 per 100 ml (SWRCB, 2005).
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: Samples were collected from Balboa Court, San Diego, California. Station identification number is MB-225.
Temporal Representation: Samples were collected from June 2001 through December 2007.
Environmental Conditions:
QAPP Information: Quality control for the bacteria analysis portion was conducted in accordance with the County of San Diego, Department Public Health Laboratory Quality Assurance Manual.
QAPP Information Reference(s): County of San Diego, 2006. Department Public Health Laboratory, Quality Assurance Manual, December 2006
 
Line of Evidence (LOE) for Decision ID 127892, Indicator Bacteria
Region 9     
Mission Bay Shoreline, at Balboa Court
 
LOE ID: 74329
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 22
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Zero of the 22 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 Balboa Court site (BW761).
Temporal Representation: Samples were collected approximately once a week from April 2, 2008 to September 23, 2008 (dry weather data only).
Environmental Conditions:
QAPP Information: The samples were collected for the Beach Watch program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 127892, Indicator Bacteria
Region 9     
Mission Bay Shoreline, at Balboa Court
 
LOE ID: 31114
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 44
Number of Exceedances: 1
 
Data and Information Type: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: Beach monitoring data was collected by the County of San Diego from June 2001 through October 2007. A total of 188 dry month (April through October) single samples were collected with 44 dry month geomeans calculated. One of the 44 geomeans exceeded the geomean water quality objective.
Data Reference: Department of Environmental Health, Ocean & Bay Recreational Water Quality Program, 2007. AB 411 monitoring data 1999 to 2007
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Geomean: Enterococcus density shall not exceed 35 per 100 ml.

Single Sample Maximum: Enterococcus density shall not exceed 104 per 100 ml (SWRCB, 2005).
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: Samples were collected from Balboa Court, San Diego, California. Station identification number is MB-225.
Temporal Representation: Samples were collected from June 2001 through October 2007.
Environmental Conditions:
QAPP Information: Quality control for the bacteria analysis portion was conducted in accordance with the County of San Diego, Department Public Health Laboratory Quality Assurance Manual.
QAPP Information Reference(s): County of San Diego, 2006. Department Public Health Laboratory, Quality Assurance Manual, December 2006
 
Line of Evidence (LOE) for Decision ID 127892, Indicator Bacteria
Region 9     
Mission Bay Shoreline, at Balboa Court
 
LOE ID: 28606
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 150
Number of Exceedances: 3
 
Data and Information Type: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: Beach monitoring data was collected by the County of San Diego from June 2001 through December 2007. A total of 150 single samples were collected with 3 samples exceeding the single sample water quality objective.
Data Reference: Department of Environmental Health, Ocean & Bay Recreational Water Quality Program, 2007. AB 411 monitoring data 1999 to 2007
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Geomean; Fecal coliform density shall not exceed 200 per 100 ml;

Single Sample Maximum; Fecal coliform density shall not exceed 400 per 100 ml (SWRCB, 2005).
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: Samples were collected from Balboa Court, San Diego, California. Station identification number is MB-225.
Temporal Representation: Samples were collected from June 2001 through December 2007.
Environmental Conditions:
QAPP Information: Quality control for the bacteria analysis portion was conducted in accordance with the County of San Diego, Department Public Health Laboratory Quality Assurance Manual.
QAPP Information Reference(s): County of San Diego, 2006. Department Public Health Laboratory, Quality Assurance Manual, December 2006
 
Line of Evidence (LOE) for Decision ID 127892, Indicator Bacteria
Region 9     
Mission Bay Shoreline, at Balboa Court
 
LOE ID: 28611
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 36
Number of Exceedances: 0
 
Data and Information Type: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: Beach monitoring data was collected by the County of San Diego from June 2001 through December 2007. A total of 150 single samples were collected and 36 geomeans calculated. None of the 36 geomeans exceeded the geomean water quality objective.
Data Reference: Department of Environmental Health, Ocean & Bay Recreational Water Quality Program, 2007. AB 411 monitoring data 1999 to 2007
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Geomean; Fecal coliform density shall not exceed 200 per 100 ml;

Single Sample Maximum; Fecal coliform density shall not exceed 400 per 100 ml (SWRCB, 2005).
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: Samples were collected from Balboa Court, San Diego, California. Station identification number is MB-225.
Temporal Representation: Samples were collected from June 2001 through December 2007.
Environmental Conditions:
QAPP Information: Quality control for the bacteria analysis portion was conducted in accordance with the County of San Diego, Department Public Health Laboratory Quality Assurance Manual.
QAPP Information Reference(s): County of San Diego, 2006. Department Public Health Laboratory, Quality Assurance Manual, December 2006
 
Line of Evidence (LOE) for Decision ID 127892, Indicator Bacteria
Region 9     
Mission Bay Shoreline, at Balboa Court
 
LOE ID: 28607
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: Beach monitoring data was collected by the County of San Diego from June 2001 through December 2007. A total of 150 single samples were collected with no samples correlated with a storm event. This information will not be used in determining a listing decision, but is of interest to the Regional Board and has been included here as additional anecdotal information.
Data Reference: National Weather Service Forecast Office, San Diego, California, Chronological Regional Temperature and Precipitation Listings by Station
  Department of Environmental Health, Ocean & Bay Recreational Water Quality Program, 2007. AB 411 monitoring data 1999 to 2007
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Geomean; Fecal coliform density shall not exceed 200 per 100 ml;

Single Sample Maximum; Fecal coliform density shall not exceed 400 per 100 ml (SWRCB, 2005).
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: Samples were collected from Balboa Court, San Diego, California. Station identification number is MB-225.
Temporal Representation: Samples were collected from June 2001 through December 2007.
Environmental Conditions: Comparisons were made for all data and data associated with storm events. A storm event was defined as 0.2 inches of rainfall within a 72 hour period.

Analyzing only storm water bacteria data is important because the majority of beach monitoring data covers the months of April through October. The data may not capture the full impacts of seasonal storm events and high bacteria levels due to storm water runoff because much of the wet season for Southern California occurs in November through March
QAPP Information: Quality control for the bacteria analysis portion was conducted in accordance with the County of San Diego, Department Public Health Laboratory Quality Assurance Manual.
QAPP Information Reference(s): County of San Diego, 2006. Department Public Health Laboratory, Quality Assurance Manual, December 2006
 
Line of Evidence (LOE) for Decision ID 127892, Indicator Bacteria
Region 9     
Mission Bay Shoreline, at Balboa Court
 
LOE ID: 74330
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 22
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Zero of the 22 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 Balboa Court site.
Temporal Representation: Samples were collected approximately once a week from April 2008 to September 2008.
Environmental Conditions:
QAPP Information: The samples were collected for the beach watch program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 127892, Indicator Bacteria
Region 9     
Mission Bay Shoreline, at Balboa Court
 
LOE ID: 31115
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 36
Number of Exceedances: 0
 
Data and Information Type: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: Beach monitoring data was collected by the County of San Diego from June 2001 through October 2007. A total of 148 dry month (April through October) single samples were collected with 36 dry month geomeans calculated. None of the 36 geomeans exceeded the geomean water quality objective.
Data Reference: Department of Environmental Health, Ocean & Bay Recreational Water Quality Program, 2007. AB 411 monitoring data 1999 to 2007
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Geomean; Fecal coliform density shall not exceed 200 per 100 ml;

Single Sample Maximum; Fecal coliform density shall not exceed 400 per 100 ml (SWRCB, 2005).
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: Samples were collected from Balboa Court, San Diego, California. Station identification number is MB-225.
Temporal Representation: Samples were collected from June 2001 through October 2007.
Environmental Conditions:
QAPP Information: Quality control for the bacteria analysis portion was conducted in accordance with the County of San Diego, Department Public Health Laboratory Quality Assurance Manual.
QAPP Information Reference(s): County of San Diego, 2006. Department Public Health Laboratory, Quality Assurance Manual, December 2006
 
Line of Evidence (LOE) for Decision ID 127892, Indicator Bacteria
Region 9     
Mission Bay Shoreline, at Balboa Court
 
LOE ID: 30108
 
Pollutant: Indicator Bacteria
LOE Subgroup: Health Advisories
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 2555
Number of Exceedances: 17
 
Data and Information Type: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: For the period from January 2001 to December 2007, there were 17 beach advisory days for this location. When a bacteriological sample exceeds water quality standards, signs are posted indicating that waters have exceeded public health standards.

Data and information on the number of beach posting were summarized by the County of San Diego in their annual San Diego County Beach Closure and Advisory Reports. The reporting period was from January 2001 to December 2007. Data used was the number of days the beach was posted with an Advisory when the ocean or bay failed to meet the bacteriological standards.
Data Reference: Department of Environmental Health, Land and Water Quality Division. San Diego County Beach Closure and Advisory Report
  County of Orange. March 2007. Annual Ocean and Bay Water Quality Report, 2006
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Code of Regulations. Title 17, Section 7960.

(a) When a public beach or public water-contact sports area fails to meet any of the standards as set forth in Section 7957 or 7958 above, the local health officer or the Department, after taking into consideration the causes therefor, may at his or its discretion close, post with warning signs, or otherwise restrict use of said public beach or public water-contact sports area, until such time as corrective action has been taken and the standards as set forth in 7957 and 7958 above are met.
Objective/Criterion Reference: California Code of Regulations, Title 17, Section 7960
 
Evaluation Guideline:
Guideline Reference: Water Quality Control Plan Ocean Waters of California. California Ocean Plan 2005. Sacramento, CA: State Water Resources Control Board, California Environmental Protection Agency
 
Spatial Representation: Bacteriological monitoring samples were collected at Balboa Court in Mission Bay.
Temporal Representation: The beach advisory covers the time frame of January 2001 -December 2007.
Environmental Conditions:
QAPP Information: Quality control for the bacteria analysis portion was conducted in accordance with the County of San Diego, Department Public Health Laboratory Quality Assurance Manual.
QAPP Information Reference(s): County of San Diego, 2006. Department Public Health Laboratory, Quality Assurance Manual, December 2006
 
Line of Evidence (LOE) for Decision ID 127892, Indicator Bacteria
Region 9     
Mission Bay Shoreline, at Balboa Court
 
LOE ID: 30339
 
Pollutant: Indicator Bacteria
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 2933
Number of Exceedances: 959
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Below is a copy of the 2006 LOE for the data supporting the listing of Mission Bay Shoreline:

Available data indicate sufficient exceedances of bacterial indicator objectives. There were 576 out of 3662 samples exceeding the single sample maximum for enterococci, 959 out of 2933 exceedances of the geomean enterococci, and 333 out samples exceeding the single sample maximum for fecal coliform (USEPA, 2007).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Title 17 C.C.R. Section 7958 states: Based on a single sample, the density of bacteria in water from each sampling station at a public beach or public water contact sports area shall not exceed:
(A) 1,000 total coliform bacteria per 100 milliliters, if the ratio of fecal/total coliform bacteria exceeds 0.1; or
(B) 10,000 total coliform bacteria per 100 milliliters; or
(C) 400 fecal coliform bacteria per 100 milliliters; or
(D) 104 enterococcus bacteria per 100 milliliters.

Based on the mean of the logarithms of the results of at least five weekly samples during any 30-day sampling period, the density of bacteria in water from any sampling station at a public beach or public water contact sports area, shall not exceed:
(A) 1,000 total coliform bacteria per 100 milliliters; or
(B) 200 fecal coliform bacteria per 100 milliliters; or
(C) 35 enterococcus bacteria per 100 milliliters (DHS, 1999).
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: In 2006, data from sampling sites along the Mission Bay shoreline were aggregated for the assessment. For 2008, the 2006 Mission Bay Shoreline segment has been split into smaller segments and each represents an area near the sampling location of the data being assessed. 'Mission Bay Shoreline, at Balboa Court' is one of the sampling locations for Mission Bay Shoreline and is considered to be part of the original listing
Temporal Representation: From 03/21/2000-10/30/2005.
Environmental Conditions:
QAPP Information: Data record: 2000-2005, San Diego County Health Dept.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 127892, Indicator Bacteria
Region 9     
Mission Bay Shoreline, at Balboa Court
 
LOE ID: 77603
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Shellfish Harvesting
 
Number of Samples: 21
Number of Exceedances: 0
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Zero of the twenty one samples exceeded the objective of 70 mpn/100ml applied as a rolling 30 day geomean.
Data Reference: Data for Region 9 Beach Watch.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan for the San Diego Basin states that at all areas where shellfish may be harvested for human consumption, the median total coliform concentration throughout the water column for any 30-day period shall not exceed 70 per 100 mL. Staff applied the objective as a rolling 30 day geometric mean consistent with other state bacteria objectives and with guidance from the National Shellfish Sanitation Program from which the objectives were taken.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at Mission Bay Shoreline, at Balboa Court.
Temporal Representation: The samples were collected from April 2008 to September 2008.
Environmental Conditions:
QAPP Information: The samples were collected for the beach watch program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 127892, Indicator Bacteria
Region 9     
Mission Bay Shoreline, at Balboa Court
 
LOE ID: 28603
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Shellfish Harvesting
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: Beach monitoring data was collected by the County of San Diego from June 2001 through December 2007. A total of 192 single samples were collected with one sample correlated with a storm event. This sample exceeded the single sample water quality objective. This information will not be used in determining a listing decision, but is of interest to the Regional Board and has been included here as additional anecdotal information.
Data Reference: Department of Environmental Health, Ocean & Bay Recreational Water Quality Program, 2007. AB 411 monitoring data 1999 to 2007
  National Weather Service Forecast Office, San Diego, California, Chronological Regional Temperature and Precipitation Listings by Station
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: From the Ocean Plan the median coliform density shall not exceed 70 per 100ml, and not more than 10 percent of the samples shall exceed 230 per 100ml (SWRCB, 2005).

Comparisons are also made for days with matching bacteria and storm event data. A storm event was defined as 0.2 inches of rainfall within a 72 hour period.
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: Samples were collected from Balboa Court, San Diego, California. Station identification number is MB-225.
Temporal Representation: Samples were collected from June 2001 through December 2007.
Environmental Conditions: Comparisons were made for all data and data associated with storm events. A storm event was defined as 0.2 inches of rainfall within a 72 hour period.

Analyzing only storm water bacteria data is important because the majority of beach monitoring data covers the months of April through October. The data may not capture the full impacts of seasonal storm events and high bacteria levels due to storm water runoff because much of the wet season for Southern California occurs in November through March
QAPP Information: Quality control for the bacteria analysis portion was conducted in accordance with the County of San Diego, Department Public Health Laboratory Quality Assurance Manual.
QAPP Information Reference(s): County of San Diego, 2006. Department Public Health Laboratory, Quality Assurance Manual, December 2006
 
Line of Evidence (LOE) for Decision ID 127892, Indicator Bacteria
Region 9     
Mission Bay Shoreline, at Balboa Court
 
LOE ID: 28601
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Shellfish Harvesting
 
Number of Samples: 192
Number of Exceedances: 11
 
Data and Information Type: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: Beach monitoring data was collected by the County of San Diego from June 2001 through December 2007. A total of 192 single samples were collected with 11 samples exceeded the single sample water quality objective.
Data Reference: Department of Environmental Health, Ocean & Bay Recreational Water Quality Program, 2007. AB 411 monitoring data 1999 to 2007
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: From the Ocean Plan the median coliform density shall not exceed 70 per 100ml, and not more than 10 percent of the samples shall exceed 230 per 100ml (SWRCB, 2005).
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: Samples were collected at Balboa Court, San Diego, California. Station identification number is MB-225.
Temporal Representation: Samples were collected from June 2001 through December 2007.
Environmental Conditions:
QAPP Information: Quality control for the bacteria analysis portion was conducted in accordance with the County of San Diego, Department Public Health Laboratory Quality Assurance Manual.
QAPP Information Reference(s): County of San Diego, 2006. Department Public Health Laboratory, Quality Assurance Manual, December 2006
 
Line of Evidence (LOE) for Decision ID 127892, Indicator Bacteria
Region 9     
Mission Bay Shoreline, at Balboa Court
 
LOE ID: 74331
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Shellfish Harvesting
 
Number of Samples: 25
Number of Exceedances: 0
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BW data for Mission Bay Shoreline, at Balboa Court to determine beneficial use support and results are as follows: 0 of 25 samples exceed the criterion for Coliform, Total.
Data Reference: Data for Region 9 Beach Watch.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan (Basin Plan 2011)states the following: At all areas where shellfish may be harvested for human consumption, ten percent of the samples collected during any 30-day period shall not exceed 230 MPN/100mL.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mission Bay Shoreline, at Balboa Court was collected at 1 monitoring site [ Balboa Ct.]
Temporal Representation: Data was collected over the time period 4/2/2008-9/23/2008.
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 127892, Indicator Bacteria
Region 9     
Mission Bay Shoreline, at Balboa Court
 
LOE ID: 28604
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 192
Number of Exceedances: 1
 
Data and Information Type: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: Beach monitoring data was collected by the County of San Diego from June 2001 through December 2007. A total of 192 single samples were collected with one sample exceeding the single sample water quality objective.
Data Reference: National Weather Service Forecast Office, San Diego, California, Chronological Regional Temperature and Precipitation Listings by Station
  Department of Environmental Health, Ocean & Bay Recreational Water Quality Program, 2007. AB 411 monitoring data 1999 to 2007
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Geomean: Total coliform density shall not exceed 1,000 per 100ml;

Single Sample Maximum: Total coliform density shall not exceed 10,000 per 100ml (SWRCB, 2005).
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: Samples were collected from Balboa Court, San Diego, California. Station identification number is MB-225.
Temporal Representation: Samples were collected from June 2001 through December 2007.
Environmental Conditions:
QAPP Information: Quality control for the bacteria analysis portion was conducted in accordance with the County of San Diego, Department Public Health Laboratory Quality Assurance Manual.
QAPP Information Reference(s): County of San Diego, 2006. Department Public Health Laboratory, Quality Assurance Manual, December 2006
 
Line of Evidence (LOE) for Decision ID 127892, Indicator Bacteria
Region 9     
Mission Bay Shoreline, at Balboa Court
 
LOE ID: 28610
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 45
Number of Exceedances: 0
 
Data and Information Type: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: Beach monitoring data was collected by the County of San Diego from June 2001 through December 2007. A total of 192 single samples were collected with 45 monthly geomeans calculated. None of the 45 geomeans exceeded the geomean water quality objective.
Data Reference: Department of Environmental Health, Ocean & Bay Recreational Water Quality Program, 2007. AB 411 monitoring data 1999 to 2007
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Geomean: Total coliform density shall not exceed 1,000 per 100ml;

Single Sample Maximum: Total coliform density shall not exceed 10,000 per 100ml (SWRCB, 2005).
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: Samples were collected from Balboa Court, San Diego, California. Station identification number is MB-225.
Temporal Representation: Samples were collected from June 2001 through December 2007.
Environmental Conditions:
QAPP Information: Quality control for the bacteria analysis portion was conducted in accordance with the County of San Diego, Department Public Health Laboratory Quality Assurance Manual.
QAPP Information Reference(s): County of San Diego, 2006. Department Public Health Laboratory, Quality Assurance Manual, December 2006
 
Line of Evidence (LOE) for Decision ID 127892, Indicator Bacteria
Region 9     
Mission Bay Shoreline, at Balboa Court
 
LOE ID: 30781
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 191
Number of Exceedances: 1
 
Data and Information Type: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: Beach monitoring data was collected by the County of San Diego from June 2001 through December 2007. A total of 192 single samples were collected of which 191 are dry weather (AB411) samples with zero samples exceeding the single sample water quality objective.
Data Reference: National Weather Service Forecast Office, San Diego, California, Chronological Regional Temperature and Precipitation Listings by Station
  Department of Environmental Health, Ocean & Bay Recreational Water Quality Program, 2007. AB 411 monitoring data 1999 to 2007
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Geomean: Total coliform density shall not exceed 1,000 per 100ml;

Single Sample Maximum: Total coliform density shall not exceed 10,000 per 100ml (SWRCB, 2005).
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: Samples were collected from Balboa Court, San Diego, California. Station identification number is MB-225.
Temporal Representation: Samples were collected from June 2001 through December 2007.
Environmental Conditions:
QAPP Information: Quality control for the bacteria analysis portion was conducted in accordance with the County of San Diego, Department Public Health Laboratory Quality Assurance Manual.
QAPP Information Reference(s): County of San Diego, 2006. Department Public Health Laboratory, Quality Assurance Manual, December 2006
 
Line of Evidence (LOE) for Decision ID 127892, Indicator Bacteria
Region 9     
Mission Bay Shoreline, at Balboa Court
 
LOE ID: 28605
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: Beach monitoring data was collected by the County of San Diego from June 2001 through December 2007. A total of 192 single samples were collected with one samples correlated with a storm event. This sample exceeded the single sample water quality objective. This information will not be used in determining a listing decision, but is of interest to the Regional Board and has been included here as additional anecdotal information.
Data Reference: National Weather Service Forecast Office, San Diego, California, Chronological Regional Temperature and Precipitation Listings by Station
  Department of Environmental Health, Ocean & Bay Recreational Water Quality Program, 2007. AB 411 monitoring data 1999 to 2007
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Geomean: Total coliform density shall not exceed 1,000 per 100ml;

Single Sample Maximum: Total coliform density shall not exceed 10,000 per 100ml (SWRCB, 2005).
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: Samples were collected from Balboa Court, San Diego, California. Station identification number is MB-225.
Temporal Representation: Samples were collected from June 2001 through December 2007.
Environmental Conditions: Comparisons were made for all data and data associated with storm events. A storm event was defined as 0.2 inches of rainfall within a 72 hour period.

Analyzing only storm water bacteria data is important because the majority of beach monitoring data covers the months of April through October. The data may not capture the full impacts of seasonal storm events and high bacteria levels due to storm water runoff because much of the wet season for Southern California occurs in November through March
QAPP Information: Quality control for the bacteria analysis portion was conducted in accordance with the County of San Diego, Department Public Health Laboratory Quality Assurance Manual.
QAPP Information Reference(s): County of San Diego, 2006. Department Public Health Laboratory, Quality Assurance Manual, December 2006
 
Line of Evidence (LOE) for Decision ID 127892, Indicator Bacteria
Region 9     
Mission Bay Shoreline, at Balboa Court
 
LOE ID: 74332
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 22
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Zero of the 22 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 Balboa Court site.
Temporal Representation: Samples were collected approximately once a week from January 2008 to September 2008.
Environmental Conditions:
QAPP Information: The samples were collected for the Beach Watch program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 127892, Indicator Bacteria
Region 9     
Mission Bay Shoreline, at Balboa Court
 
LOE ID: 31116
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 44
Number of Exceedances: 0
 
Data and Information Type: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: Beach monitoring data was collected by the County of San Diego from June 2001 through October 2007. A total of 109 dry month (April through October) single samples were collected with 44 dry month geomeans calculated. None of the 44 geomeans exceeded the geomean water quality objective.
Data Reference: Department of Environmental Health, Ocean & Bay Recreational Water Quality Program, 2007. AB 411 monitoring data 1999 to 2007
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Geomean: Total coliform density shall not exceed 1,000 per 100ml;

Single Sample Maximum: Total coliform density shall not exceed 10,000 per 100ml (SWRCB, 2005).
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: Samples were collected from Balboa Court, San Diego, California. Station identification number is MB-225.
Temporal Representation: Samples were collected from June 2001 through October 2007.
Environmental Conditions:
QAPP Information: Quality control for the bacteria analysis portion was conducted in accordance with the County of San Diego, Department Public Health Laboratory Quality Assurance Manual.
QAPP Information Reference(s): County of San Diego, 2006. Department Public Health Laboratory, Quality Assurance Manual, December 2006
 
Line of Evidence (LOE) for Decision ID 127892, Indicator Bacteria
Region 9     
Mission Bay Shoreline, at Balboa Court
 
LOE ID: 220560
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for Mission Bay Shoreline, at Balboa Court to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the geomean water quality threshold for Enterococcus. This is a six week rolling geomean that is calculated weekly. This data is for an AB411 beach. This LOE specifically corresponds with dry weather samples and only includes samples collected between April 1 and October 31 of each year.
Data Reference: Coastal Counties in Region 9 including: Orange, San Diego, and Los Angeles counties.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective to protect the REC-1 beneficial for all saline waters, is a geometric mean (GM) of Enterococci not to exceed 30 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: The samples were collected at 1 monitoring site(s), station(s): MB-225
Temporal Representation: The samples were collected between the days of 2019-04-02 and 2019-06-11 .
Environmental Conditions:
QAPP Information: QAPP for San Diego County Beachwatch data
QAPP Information Reference(s): QAPP for San Diego County Beachwatch data for the 2020 Integrated Report.
 
Line of Evidence (LOE) for Decision ID 127892, Indicator Bacteria
Region 9     
Mission Bay Shoreline, at Balboa Court
 
LOE ID: 220571
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for Mission Bay Shoreline, at Balboa Court to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the Statistical Threshold Value (STV) water quality threshold for Enterococcus. The STV is based on a 10% exceedance rate that is calculated monthly. This data is for an AB411 beach. This LOE specifically corresponds with dry weather samples and only includes samples collected between April 1 and October 31 of each year.
Data Reference: Coastal Counties in Region 9 including: Orange, San Diego, and Los Angeles counties.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective to protect the REC-1 beneficial for all saline waters, is a Statistical Threshold Value (STV) of Enterococci of 110 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): MB-225
Temporal Representation: The samples were collected between the days of 2019-04-02 and 2019-06-11 .
Environmental Conditions:
QAPP Information: QAPP for San Diego County Beachwatch data
QAPP Information Reference(s): QAPP for San Diego County Beachwatch data for the 2020 Integrated Report.