Final California 2010 Integrated Report (303(d) List/305(b) Report)

Supporting Information

Regional Board 9 - San Diego Region

Water Body Name: Pacific Ocean Shoreline, Rancho Santa Fe HSA, at Powerhouse Park
Water Body ID: CAC9051100020090216230114
Water Body Type: Coastal & Bay Shoreline
 
DECISION ID
16375
Region 9     
Pacific Ocean Shoreline, Rancho Santa Fe HSA, at Powerhouse Park
 
Pollutant: Enterococcus
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the 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. Five of the samples exceed the water quality objective for enterococcus .

The coastal beach at this water segment is identified as an AB411 beach. To comply with the requirements of AB411 the dry weather data collected during the time frame of April 1st to October 31st is assessed using a four percent exceedance percentage, as described in section 3.3 and 4.3 of the Listing Policy. An assessment for dry weather single sample and the geometric mean calculation was conducted and two additional lines of evidence are available in the administrative record. Four of 164 dry weather single samples and one of 25 geometric mean calculations exceeded the criteria for recreational use and this does not exceed the allowable limit based on the application of a four percent exceedance percentage (AB411) to section 3.3 of the Listing Policy.


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 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. Five of 169 samples exceeded the enterococcus water quality objective and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy.
4. Four of 164 dry weather single samples exceeded the criteria for recreational use and this does not exceed the allowable limit based on the application of a four percent exceedance percentage (AB411) to section 3.3 of the Listing Policy
5. One of 25 geometric mean calculations exceeded the criteria for recreational use and this does not exceed the allowable limit based on the application of a four percent exceedance percentage (AB411) to section 3.3 of the Listing Policy.
6. 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 the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards for the pollutant are not exceeded.
 
USEPA Action (if applicable):
 
 
Line of Evidence (LOE) for Decision ID 16375, Enterococcus
Region 9     
Pacific Ocean Shoreline, Rancho Santa Fe HSA, at Powerhouse Park
 
LOE ID: 28208
 
Pollutant: Indicator Bacteria
LOE Subgroup: Health Advisories
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 2555
Number of Exceedances: 2
 
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 two beach advisory days for this location. Bacteriological samples are collected on a weekly basis from April through October. 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: County of Orange. March 2007. Annual Ocean and Bay Water Quality Report, 2006
  Department of Environmental Health, Land and Water Quality Division. San Diego County Beach Closure and Advisory Report
 
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 the shoreline near Powerhouse Park in Del Mar, CA.
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 16375, Enterococcus
Region 9     
Pacific Ocean Shoreline, Rancho Santa Fe HSA, at Powerhouse Park
 
LOE ID: 27109
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 40
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 January 2004 through December 2007. A total of 169 single samples were collected with 40 monthly geomeans calculated. One of the 40 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 at 15th St. Del Mar City Beach, Del Mar, California. Station identification number is EH-360.
Temporal Representation: Samples were collected from January 2004 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 16375, Enterococcus
Region 9     
Pacific Ocean Shoreline, Rancho Santa Fe HSA, at Powerhouse Park
 
LOE ID: 27106
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 5
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 January 2004 through December 2007. A total of 169 single samples were collected with five samples correlated with a storm event. One of the five samples exceeded 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: 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 at 15th St. Del Mar City Beach, Del Mar, California. Station identification number is EH-360.
Temporal Representation: Samples were collected from January 2004 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 16375, Enterococcus
Region 9     
Pacific Ocean Shoreline, Rancho Santa Fe HSA, at Powerhouse Park
 
LOE ID: 30612
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 164
Number of Exceedances: 4
 
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 January 2004 through December 2007. A total of 169 single samples were collected of which 164 are dry weather (AB411) samples with four 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 at 15th St. Del Mar City Beach, Del Mar, California. Station identification number is EH-360.
Temporal Representation: Samples were collected from January 2004 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 Orange. Quality Assurance/Quality Control Manual, February 2004 Bacteria specific
  County of San Diego, 2006. Department Public Health Laboratory, Quality Assurance Manual, December 2006
 
Line of Evidence (LOE) for Decision ID 16375, Enterococcus
Region 9     
Pacific Ocean Shoreline, Rancho Santa Fe HSA, at Powerhouse Park
 
LOE ID: 31239
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 25
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 2004 through October 2007. A total of 107 dry month (April through October) single samples were collected with 25 dry month geomeans calculated. One of the 25 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 at 15th St. Del Mar City Beach, Del Mar, California. Station identification number is EH-360.
Temporal Representation: Samples were collected from June 2004 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 16375, Enterococcus
Region 9     
Pacific Ocean Shoreline, Rancho Santa Fe HSA, at Powerhouse Park
 
LOE ID: 27105
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 169
Number of Exceedances: 5
 
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 January 2004 through December 2007. A total of 169 single samples were collected with 5 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 at 15th St. Del Mar City Beach, Del Mar, California. Station identification number is EH-360.
Temporal Representation: Samples were collected from January 2004 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 Orange. Quality Assurance/Quality Control Manual, February 2004 Bacteria specific
  County of San Diego, 2006. Department Public Health Laboratory, Quality Assurance Manual, December 2006
 
 
DECISION ID
16373
Region 9     
Pacific Ocean Shoreline, Rancho Santa Fe HSA, at Powerhouse Park
 
Pollutant: Fecal Coliform
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the 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. Two of the samples exceed the water quality objective for fecal coliform.

This water body segment is identified as an AB411 beach and data collected during the time frame of April 1st to October 31st (dry weather) is assessed using a four percent exceedance percentage (section 3.3 of Listing Policy). There are two additional lines of evidence for dry weather single sample and geometric mean calculations. Two of 104 samples exceeded the recreational use single sample criteria and 0 of 16 geo-metric mean calculations exceeded the geo-metric mean criteria.

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 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. Two of 107 samples exceed the fecal coliform water quality objective and this exceeds the allowable frequency listed in Table 3.2 of the Listing Policy.
4. Two of 104 samples exceeded the fecal coliform recreational use water quality objective and this does not exceed the allowable limit listed in Table 3.2 (at a four percent exceedance percentage – AB411) of the Listing Policy.
5. Zero of 16 geo-metric mean calculations exceeded the recreational use geo-metric mean criteria. This does not exceed the allowable limit in Table 3.2 (at a four percent exceedance percentage – AB411).
6. 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 the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards for the pollutant are not exceeded.
 
USEPA Action (if applicable):
 
 
Line of Evidence (LOE) for Decision ID 16373, Fecal Coliform
Region 9     
Pacific Ocean Shoreline, Rancho Santa Fe HSA, at Powerhouse Park
 
LOE ID: 27108
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 26
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 January 2004 through December 2007. A total of 107 single samples were collected and 26 geomeans calculated. None of the 26 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 at 15th St. Del Mar City Beach, Del Mar, California. Station identification number is EH-360.
Temporal Representation: Samples were collected from January 2004 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 16373, Fecal Coliform
Region 9     
Pacific Ocean Shoreline, Rancho Santa Fe HSA, at Powerhouse Park
 
LOE ID: 27104
 
Pollutant: Fecal Coliform
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: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: Beach monitoring data was collected by the County of San Diego from January 2004 through December 2007. A total of 107 single samples were collected with three samples correlated with a storm event. No sample exceeded 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; 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 at 15th St. Del Mar City Beach, Del Mar, California. Station identification number is EH-360.
Temporal Representation: Samples were collected from January 2004 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 16373, Fecal Coliform
Region 9     
Pacific Ocean Shoreline, Rancho Santa Fe HSA, at Powerhouse Park
 
LOE ID: 27103
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 107
Number of Exceedances: 2
 
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 January 2004 through December 2007. A total of 107 single samples were collected with two 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 at 15th St. Del Mar City Beach, Del Mar, California. Station identification number is EH-360.
Temporal Representation: Samples were collected from January 2004 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 16373, Fecal Coliform
Region 9     
Pacific Ocean Shoreline, Rancho Santa Fe HSA, at Powerhouse Park
 
LOE ID: 31240
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 16
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 2004 through October 2007. A total of 65 dry month (April through October) single samples were collected with 16 dry month geomeans calculated. None of the 16 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 at 15th St. Del Mar City Beach, Del Mar, California. Station identification number is EH-360.
Temporal Representation: Samples were collected from June 2004 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 16373, Fecal Coliform
Region 9     
Pacific Ocean Shoreline, Rancho Santa Fe HSA, at Powerhouse Park
 
LOE ID: 30722
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 104
Number of Exceedances: 2
 
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 January 2004 through December 2007. A total of 107 single samples were collected of which 104 are dry weather (AB411) samples with two 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 at 15th St. Del Mar City Beach, Del Mar, California. Station identification number is EH-360.
Temporal Representation: Samples were collected from January 2004 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 16373, Fecal Coliform
Region 9     
Pacific Ocean Shoreline, Rancho Santa Fe HSA, at Powerhouse Park
 
LOE ID: 28208
 
Pollutant: Indicator Bacteria
LOE Subgroup: Health Advisories
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 2555
Number of Exceedances: 2
 
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 two beach advisory days for this location. Bacteriological samples are collected on a weekly basis from April through October. 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: County of Orange. March 2007. Annual Ocean and Bay Water Quality Report, 2006
  Department of Environmental Health, Land and Water Quality Division. San Diego County Beach Closure and Advisory Report
 
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 the shoreline near Powerhouse Park in Del Mar, CA.
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
 
 
DECISION ID
16372
Region 9     
Pacific Ocean Shoreline, Rancho Santa Fe HSA, at Powerhouse Park
 
Pollutant: Total Coliform
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the 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.

Six lines of evidence are available in the administrative record to assess this pollutant. Eleven of the samples exceed the water quality objectives for Shellfish Harvesting.

The coastal beach at this water segment is identified as an AB411 beach. To comply with the requirements of AB411 the dry weather data collected during the time frame of April 1st to October 31st is assessed using a four percent exceedance percentage, as described in section 3.3 (and 4.3) of the Listing Policy. An assessment for dry weather single sample and the geometric mean calculation was conducted and two additional lines of evidence are available in the administrative record. One of 164 single samples and none of 25 geometric mean calculations exceeded the criteria for recreational use and this does not exceed the allowable limit based on the application of a four percent exceedance percentage (AB411) to section 3.3 of the Listing Policy.

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 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. Eleven of 169 samples exceeded the Shellfish Harvesting water quality objectives and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy.
4. One of 164 dry weather single samples exceeded the total coliform criteria for recreational use and this does not exceed the allowable limit (at a four percent exceedance percentage - AB411) in section 3.3 of the Listing Policy.
5. None of 25 dry weather geometric mean calculations exceeded the total coliform criteria for recreational use and this does exceed the allowable limit (at a four percent exceedance percentage - AB411) in section 3.3 of the Listing Policy.
6. 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 the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards for the pollutant are not exceeded.
 
USEPA Action (if applicable):
 
 
Line of Evidence (LOE) for Decision ID 16372, Total Coliform
Region 9     
Pacific Ocean Shoreline, Rancho Santa Fe HSA, at Powerhouse Park
 
LOE ID: 27102
 
Pollutant: Total Coliform
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: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: Beach monitoring data was collected by the County of San Diego from January 2004 through December 2007. A total of 169 single samples were collected with five samples correlated with a storm event. None of the five samples exceeded 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 at 15th St. Del Mar City Beach, Del Mar, California. Station identification number is EH-360.
Temporal Representation: Samples were collected from January 2004 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 16372, Total Coliform
Region 9     
Pacific Ocean Shoreline, Rancho Santa Fe HSA, at Powerhouse Park
 
LOE ID: 27098
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Shellfish Harvesting
 
Number of Samples: 169
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 January 2004 through December 2007. A total of 169 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 15th St. Del Mar, Del Mar City Beach, California. Station identification number is EH-360.
Temporal Representation: Samples were collected from January 2004 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 16372, Total Coliform
Region 9     
Pacific Ocean Shoreline, Rancho Santa Fe HSA, at Powerhouse Park
 
LOE ID: 27099
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Shellfish Harvesting
 
Number of Samples: 5
Number of Exceedances: 2
 
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 January 2004 through December 2007. A total of 169 single samples were collected with five samples correlated with a storm event. Two of the five samples exceeded 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: 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 at 15th St. Del Mar City Beach, Del Mar, California. Station identification number is EH-360.
Temporal Representation: Samples were collected from January 2004 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 16372, Total Coliform
Region 9     
Pacific Ocean Shoreline, Rancho Santa Fe HSA, at Powerhouse Park
 
LOE ID: 31241
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 25
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 2004 through October 2007. A total of 25 dry month (April through October) single samples were collected with 25 dry month geomeans calculated. None of the 25 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 at 15th St. Del Mar City Beach, Del Mar, California. Station identification number is EH-360.
Temporal Representation: Samples were collected from June 2004 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 16372, Total Coliform
Region 9     
Pacific Ocean Shoreline, Rancho Santa Fe HSA, at Powerhouse Park
 
LOE ID: 30827
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 164
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 January 2004 through December 2007. A total of 169 single samples were collected of which 164 are dry weather (AB411) samples 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 at 15th St. Del Mar City Beach, Del Mar, California. Station identification number is EH-360.
Temporal Representation: Samples were collected from January 2004 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 16372, Total Coliform
Region 9     
Pacific Ocean Shoreline, Rancho Santa Fe HSA, at Powerhouse Park
 
LOE ID: 28208
 
Pollutant: Indicator Bacteria
LOE Subgroup: Health Advisories
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 2555
Number of Exceedances: 2
 
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 two beach advisory days for this location. Bacteriological samples are collected on a weekly basis from April through October. 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: County of Orange. March 2007. Annual Ocean and Bay Water Quality Report, 2006
  Department of Environmental Health, Land and Water Quality Division. San Diego County Beach Closure and Advisory Report
 
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 the shoreline near Powerhouse Park in Del Mar, CA.
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 16372, Total Coliform
Region 9     
Pacific Ocean Shoreline, Rancho Santa Fe HSA, at Powerhouse Park
 
LOE ID: 27100
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 169
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 January 2004 through December 2007. A total of 169 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 at 15th St. Del Mar City Beach, Del Mar, California. Station identification number is EH-360.
Temporal Representation: Samples were collected from January 2004 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 16372, Total Coliform
Region 9     
Pacific Ocean Shoreline, Rancho Santa Fe HSA, at Powerhouse Park
 
LOE ID: 27107
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 40
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 January 2004 through December 2007. A total of 169 single samples were collected with 40 monthly geomeans calculated. None of the 40 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 at 15th St. Del Mar City Beach, Del Mar, California. Station identification number is EH-360.
Temporal Representation: Samples were collected from January 2004 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