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

Supporting Information

Regional Board 9 - San Diego Region

Water Body Name: Pacific Ocean Shoreline, Otay Valley HA, north of Palm Avenue Jetty
Water Body ID: CAC9102000020120705164222
Water Body Type: Coastal & Bay Shoreline
 
DECISION ID
127971
Region 9     
Pacific Ocean Shoreline, Otay Valley HA, north of Palm Avenue Jetty
 
Pollutant: Indicator Bacteria
Final Listing Decision: 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)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2033
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.

Four lines of evidence are available in the administrative record to assess this pollutant. Seven of the eight samples exceed the STV threshold for Enterococci. Eight of the 19 samples exceed the SSM threshold for Fecal Coliform. [Two of two samples exceeded the GM threshold for Enterococci, and zero of one sample exceeded the GM threshold for Fecal Coliform, but these sample sizes are insufficient to determine the beneficial use support rating with the power and confidence of the Listing Policy.]

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. Seven of eight samples exceeded the Enterococci water quality threshold and eight of 19 samples exceeded the Fecal Coliform water quality threshold for the protection of REC-1, and these 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.

The Water Quality Control Plan for Ocean Waters (“Ocean Plan”) contains two bacteria water quality objectives applicable to the REC-1 beneficial use: a fecal coliform water quality objective and an enterococci water quality objective. 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 fecal coliform and enterococci objectives.

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 from April 1 through October 31 only.
 
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: The Water Quality Control Plan for Ocean Waters (“Ocean Plan”) contains two bacteria water quality objectives applicable to the REC-1 beneficial use: a fecal coliform water quality objective and an enterococci water quality objective. 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 fecal coliform and enterococci objectives.

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 from April 1 through October 31 only.
 
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 127971, Indicator Bacteria
Region 9     
Pacific Ocean Shoreline, Otay Valley HA, north of Palm Avenue Jetty
 
LOE ID: 220506
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 19
Number of Exceedances: 8
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for Pacific Ocean Shoreline, Otay Valley HA, north of Palm Avenue Jetty to determine beneficial use support and the results are as follows: 8 of the 19 samples exceeded the water quality threshold for Coliform, Fecal. The water quality threshold is based on a Single Sample Maximum (SSM) value that is calculated daily.
Data Reference: Coastal Counties in Region 9 including: Orange, San Diego, and Los Angeles counties.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Ocean Plan (SWRCB 2019) states that the Single Sample Maximum fecal coliform density not exceed 400 per 100 mL.
Objective/Criterion Reference: SWRCB. 2005. Water Quality Control Plan, Ocean Waters of California (Ocean Plan). California Environmental Protection Agency, State Water Resources Control Board. February 2, 2019
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): PL-010
Temporal Representation: The samples were collected between the days of 2011-04-18 and 2012-04-27 .
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 127971, Indicator Bacteria
Region 9     
Pacific Ocean Shoreline, Otay Valley HA, north of Palm Avenue Jetty
 
LOE ID: 220333
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Shellfish Harvesting
 
Number of Samples: 19
Number of Exceedances: 16
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for Pacific Ocean Shoreline, Otay Valley HA, north of Palm Avenue Jetty to determine beneficial use support and the results are as follows: 16 of the 19 samples exceeded the water quality threshold for Coliform, Total. The water quality threshold for shellfish is based on the median concentration of Total Coliform at each station, and is calculated as a 30-day rolling median.
Data Reference: Coastal Counties in Region 9 including: Orange, San Diego, and Los Angeles counties.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Ocean Plan (SWRCB 2019) states that the median total coliform density shall not exceed 70 per 100 mL.
Objective/Criterion Reference: SWRCB. 2005. Water Quality Control Plan, Ocean Waters of California (Ocean Plan). California Environmental Protection Agency, State Water Resources Control Board. February 2, 2019
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): PL-010
Temporal Representation: The samples were collected between the days of 2011-04-18 and 2012-04-27 .
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 127971, Indicator Bacteria
Region 9     
Pacific Ocean Shoreline, Otay Valley HA, north of Palm Avenue Jetty
 
LOE ID: 219950
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Shellfish Harvesting
 
Number of Samples: 19
Number of Exceedances: 16
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for Pacific Ocean Shoreline, Otay Valley HA, north of Palm Avenue Jetty to determine beneficial use support and the results are as follows: 16 of the 19 samples exceeded the water quality threshold for Coliform, Total. The water quality threshold is based on a 10% exceedance rate that is calculated for a 30-Day peroid.
Data Reference: Coastal Counties in Region 9 including: Orange, San Diego, and Los Angeles counties.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Ocean Plan (SWRCB 2019) states that not more than 10 percent of the total coliform samples shall exceed 230 per 100 mL.
Objective/Criterion Reference: SWRCB. 2005. Water Quality Control Plan, Ocean Waters of California (Ocean Plan). California Environmental Protection Agency, State Water Resources Control Board. February 2, 2019
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): PL-010
Temporal Representation: The samples were collected between the days of 2011-04-18 and 2012-04-27 .
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 127971, Indicator Bacteria
Region 9     
Pacific Ocean Shoreline, Otay Valley HA, north of Palm Avenue Jetty
 
LOE ID: 220425
 
Pollutant: Fecal Coliform
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: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for Pacific Ocean Shoreline, Otay Valley HA, north of Palm Avenue Jetty to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the water quality threshold for Coliform, Fecal. The water quality threshold is based on a 30-Day rolling geomean.
Data Reference: Coastal Counties in Region 9 including: Orange, San Diego, and Los Angeles counties.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Ocean Plan (SWRCB 2019) states that the 30 day geometric mean of fecal coliform density not exceed 200 per 100 mL, calculated based on the five most recent samples from each site.
Objective/Criterion Reference: SWRCB. 2005. Water Quality Control Plan, Ocean Waters of California (Ocean Plan). California Environmental Protection Agency, State Water Resources Control Board. February 2, 2019
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): PL-010
Temporal Representation: The samples were collected between the days of 2011-04-18 and 2012-04-27 .
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 127971, Indicator Bacteria
Region 9     
Pacific Ocean Shoreline, Otay Valley HA, north of Palm Avenue Jetty
 
LOE ID: 220435
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 8
Number of Exceedances: 7
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for Pacific Ocean Shoreline, Otay Valley HA, north of Palm Avenue Jetty to determine beneficial use support and the results are as follows: 7 of the 8 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.
Data Reference: Coastal Counties in Region 9 including: Orange, San Diego, and Los Angeles counties.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Ocean Plan (SWRCB 2019) states that the bacteria water quality objective to protect the REC-1 beneficial for all ocean waters for Enterococci is a statistical value threshold (STV) of 110 cfu/100 mL. The STV shall not be exceeded by more than 10 percent of the samples collected in a calendar month, calculated in a static manner.
Objective/Criterion Reference: SWRCB. 2005. Water Quality Control Plan, Ocean Waters of California (Ocean Plan). California Environmental Protection Agency, State Water Resources Control Board. February 2, 2019
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): PL-010
Temporal Representation: The samples were collected between the days of 2010-12-23 and 2012-04-27 .
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 127971, Indicator Bacteria
Region 9     
Pacific Ocean Shoreline, Otay Valley HA, north of Palm Avenue Jetty
 
LOE ID: 220421
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 2
Number of Exceedances: 2
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for Pacific Ocean Shoreline, Otay Valley HA, north of Palm Avenue Jetty to determine beneficial use support and the results are as follows: 2 of the 2 samples exceeded the geomean water quality threshold for Enterococcus. This is a six week rolling geomean that is calculated weekly.
Data Reference: Coastal Counties in Region 9 including: Orange, San Diego, and Los Angeles counties.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Ocean Plan (SWRCB 2019) states that the bacteria water quality objective to protect the REC-1 beneficial for all ocean waters for Enterococci is a geometric mean (GM) of 30 cfu/100 mL. The waterbody GM shall not be greater that the GM magnitude in any six-week interval, calculated weekly.
Objective/Criterion Reference: SWRCB. 2005. Water Quality Control Plan, Ocean Waters of California (Ocean Plan). California Environmental Protection Agency, State Water Resources Control Board. February 2, 2019
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): PL-010
Temporal Representation: The samples were collected between the days of 2010-12-23 and 2012-04-27 .
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 127971, Indicator Bacteria
Region 9     
Pacific Ocean Shoreline, Otay Valley HA, north of Palm Avenue Jetty
 
LOE ID: 74961
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Shellfish Harvesting
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Beach Watch data for Pacific Ocean Shoreline, Otay Valley HA, north of Palm Avenue Jetty to determine beneficial use support and results are as follows: 0 of 3 samples exceed the criterion for Coliform, Total.
Data Reference: Data for Region 9 Beach Watch.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Ocean Plan states that at all areas where shellfish may be harvested for human consumption, not more than 10 percent of the samples shall exceed 230 per 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 Shoreline, Otay Valley HA, north of Palm Avenue Jetty was collected at 1 monitoring site [ Palm Ave]
Temporal Representation: Data was collected over the time period 5/25/2008-5/6/2010.
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):