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

Supporting Information

Regional Board 9 - San Diego Region

Water Body Name:	Loma Alta Slough
Water Body ID:	CAE9041000019991117150520
Water Body Type:	Estuary


DECISION ID	16561	Region 9
Loma Alta Slough

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. Three lines of evidence are available in the administrative record to assess this pollutant. Nine of the 254 samples exceed the water quality objective. 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 171 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. Eight of 220 single samples and 1 of 34 geomean samples exceeded the Basin Plan objective and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. One of 171 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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board..

USEPA Action (if applicable):

Line of Evidence (LOE) for Decision ID 16561, Enterococcus	Region 9
Loma Alta Slough

LOE ID:

27140

Pollutant:

Enterococcus

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

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 October 2004 through December 2007. A total of 186 single samples were collected with 15 samples correlated with a storm event. Six of the 15 single 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:

Single Sample Maximum: Enterococcus density shall not exceed 104 per 100 ml;

Geomean: Enterococcus density shall not exceed 35 per 100 ml (SWRCB, 2005).

Comparisons to water quality objectives 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.

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 Pacific Ocean Shoreline, 500 feet north of Loma Alta outlet in the Loma Alta HA.

Temporal Representation:

Samples were collected from October 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 16561, Enterococcus	Region 9
Loma Alta Slough

LOE ID:

27138

Pollutant:

Enterococcus

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Non-Contact Recreation

Number of Samples:

Number of Exceedances:

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 Januray 2004 through December 2007. A total of 186 single samples were collected with 34 monthly geomeans calculated. Only one of the 34 geomeans exceed 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:

Single Sample Maximum: Enterococcus density shall not exceed 104 per 100 ml;

Geomean: Enterococcus density shall not exceed 35 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 500 feet north of the Loma Alta Slough outlet.

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 16561, Enterococcus	Region 9
Loma Alta Slough

LOE ID:

31337

Pollutant:

Enterococcus

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

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 103 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:

Single Sample Maximum: Enterococcus density shall not exceed 104 per 100 ml;

Geomean: Enterococcus density shall not exceed 35 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 Pacific Ocean Shoreline, 500 feet north of Loma Alta outlet in the Loma Alta HA.

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 16561, Enterococcus	Region 9
Loma Alta Slough

LOE ID:

27137

Pollutant:

Enterococcus

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

186

Number of Exceedances:

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 Januray 2004 through December 2007. A total of 186 single samples were collected with 7 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:

Single Sample Maximum: Enterococcus density shall not exceed 104 per 100 ml;

Geomean: Enterococcus density shall not exceed 35 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 Pacific Ocean Shoreline, 500 feet north of Loma Alta outlet in the Loma Alta HA.

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 16561, Enterococcus	Region 9
Loma Alta Slough

LOE ID:

30542

Pollutant:

Enterococcus

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

171

Number of Exceedances:

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 Januray 2004 through December 2007. A total of 186 single samples were collected of which 171 are dry weather (AB411) samples and one sample 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:

Single Sample Maximum: Enterococcus density shall not exceed 104 per 100 ml;

Geomean: Enterococcus density shall not exceed 35 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 Pacific Ocean Shoreline, 500 feet north of Loma Alta outlet in the Loma Alta HA.

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 16561, Enterococcus	Region 9
Loma Alta Slough

LOE ID:

27142

Pollutant:

Enterococcus

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

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 186 single samples were collected with 34 monthly geomeans calculated. Only one of the 34 geomeans exceed 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:

Single Sample Maximum: Enterococcus density shall not exceed 104 per 100 ml;

Geomean: Enterococcus density shall not exceed 35 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 Pacific Ocean Shoreline, 500 feet north of Loma Alta outlet in the Loma Alta HA.

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


DECISION ID	16563	Region 9
Loma Alta Slough

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. Two lines of evidence are available in the administrative record to assess this pollutant. Seven of the 220 samples exceed the water quality objective. 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 was conducted and there is one additional line of evidence available in the administrative record. Zero 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. Seven of the 220 samples exceeded the Basin Plan objective and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Zero 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. 5. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

USEPA Action (if applicable):

Line of Evidence (LOE) for Decision ID 16563, Fecal Coliform	Region 9
Loma Alta Slough

LOE ID:

27110

Pollutant:

Fecal Coliform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

186

Number of Exceedances:

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 186 single samples were collected with 7 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:

Single Sample Maximum: Fecal coliform density shall not exceed 400 per 100 ml;

Geomean: Fecal coliform density shall not exceed 200 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 Pacific Ocean Shoreline, 500 feet north of Loma Alta outlet in the Loma Alta HA.

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 16563, Fecal Coliform	Region 9
Loma Alta Slough

LOE ID:

27122

Pollutant:

Fecal Coliform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

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 186 single samples were collected with 15 samples correlated with a storm event. Five of the 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:

Single Sample Maximum: Fecal coliform density shall not exceed 400 per 100 ml;

Geomean: Fecal coliform density shall not exceed 200 per 100ml (SWRCB, 2005).

Comparisons to water quality objectives 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.

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 Pacific Ocean Shoreline, 500 feet north of Loma Alta outlet in the Loma Alta HA.

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 16563, Fecal Coliform	Region 9
Loma Alta Slough

LOE ID:

27136

Pollutant:

Fecal Coliform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

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 Januray 2004 through December 2007. A total of 186 single samples were collected with 34 geomeans calculated. None of the 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:

Single Sample Maximum: Fecal coliform density shall not exceed 400 per 100 ml;

Geomean: Fecal coliform density shall not exceed 200 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 Pacific Ocean Shoreline, 500 feet north of Loma Alta outlet in the Loma Alta HA.

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 16563, Fecal Coliform	Region 9
Loma Alta Slough

LOE ID:

31338

Pollutant:

Fecal Coliform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

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 103 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:

Single Sample Maximum: Fecal coliform density shall not exceed 400 per 100 ml;

Geomean: Fecal coliform density shall not exceed 200 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 Pacific Ocean Shoreline, 500 feet north of Loma Alta outlet in the Loma Alta HA.

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


DECISION ID	16565	Region 9
Loma Alta Slough

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. Three lines of evidence are available in the administrative record to assess this pollutant. Fifteen of the 354 samples exceed the water quality objective. 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 geometric mean calculation was conducted and one additional line of evidence is available in the administrative record. Zero 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. Fifteen of the 354 samples exceeded the Basin Plan objectives and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. 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. 5. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

USEPA Action (if applicable):

Line of Evidence (LOE) for Decision ID 16565, Total Coliform	Region 9
Loma Alta Slough

LOE ID:

26903

Pollutant:

Total Coliform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PWS pathogen monitoring (ambient water)

Data Used to Assess Water Quality:

Shoreline beach monitoring data was collected by the County of San Diego from June 2004 through October 2007. The number of samples collected for total coliform analysis was 186. None of the 34 samples exceeded the single sample geomean maximum total coliform standard.

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 (SWRCB, 2005).
Single Sample Maximum: Total coliform density shall not exceed 10,000 per 100ml;

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 Pacific Ocean Shoreline, 500 feet north of Loma Alta outlet in the Loma Alta HA.

Temporal Representation:

Samples were collected almost monthly from January 2004 through October 2007.

Environmental Conditions:

QAPP Information:

Quality control for the bacteria analysis portion of this study was conducted in accordance with the County of San Diego's Quality beach monitoring program.

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 16565, Total Coliform	Region 9
Loma Alta Slough

LOE ID:

26902

Pollutant:

Total Coliform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Shellfish Harvesting

Number of Samples:

134

Number of Exceedances:

Data and Information Type:

PWS pathogen monitoring (ambient water)

Data Used to Assess Water Quality:

Shoreline beach monitoring data was collected by the County of San Diego from June 2004 through October 2007. The number of samples collected for total coliform analysis was 134. Of the 134 samples, 15 exceeded the single sample maximum total coliform standard for shellfish harvesting.

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 total coliform density shall not exceed 70 per 100 ml, and not more than 10 percent of the samples shall exceed 230 per 100 ml.

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 Pacific Ocean Shoreline, 500 feet north of Loma Alta outlet in the Loma Alta HA.

Temporal Representation:

Samples were collected weekly from June 2004 through October 2007.

Environmental Conditions:

QAPP Information:

Quality control for the bacteria analysis portion of this study was conducted in accordance with the County of San Diego's Quality beach monitoring program.

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 16565, Total Coliform	Region 9
Loma Alta Slough

LOE ID:

27061

Pollutant:

Total Coliform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PWS pathogen monitoring (ambient water)

Data Used to Assess Water Quality:

Shoreline beach monitoring data was collected by the County of San Diego from June 2004 through December 2007. The number of samples collected for total coliform analysis was 186 with 15 samples correlated with a storm event. Only 3 of the 15 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 (SWRCB, 2005).

Single Sample Maximum: Total coliform density shall not exceed 10,000 per 100ml;

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 Pacific Ocean Shoreline, 500 feet north of Loma Alta outlet in the Loma Alta HA.

Temporal Representation:

Samples were collected weekly from June 2004 through December 2007.

Environmental Conditions:

Comparisons were 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.

QAPP Information:

Quality control for the bacteria analysis portion of this study was conducted in accordance with the County of San Diego's Quality beach monitoring program.

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 16565, Total Coliform	Region 9
Loma Alta Slough

LOE ID:

31339

Pollutant:

Total Coliform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

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 103 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:

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 (SWRCB, 2005).

Single Sample Maximum: Total coliform density shall not exceed 10,000 per 100ml;

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 Pacific Ocean Shoreline, 500 feet north of Loma Alta outlet in the Loma Alta HA.

Temporal Representation:

Samples were collected weekly from June 2004 through October 2007.

Environmental Conditions:

QAPP Information:

Quality control for the bacteria analysis portion of this study was conducted in accordance with the County of San Diego's Quality beach monitoring program.

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 16565, Total Coliform	Region 9
Loma Alta Slough

LOE ID:

26879

Pollutant:

Total Coliform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Shellfish Harvesting

Number of Samples:

Number of Exceedances:

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 2006. A total of 15 single samples were collected with 12 samples correlated with a storm event. From the 12 samples only one exceeded single sample water quality objective.

Data Reference:

The National Pollutant Discharge Elimination System (NPDES) Municipal Stormwater Permit, Coastal Storm Drain Outfall Program. Bacteria Shoreline Data. 2002 through 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 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.

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 Pacific Ocean Shoreline, 500 feet north of Loma Alta outlet in the Loma Alta HA.

Temporal Representation:

Samples were collected one to five times annually for a period of three years from October 2004 through December 2007.

Environmental Conditions:

QAPP Information:

Quality control for the bacteria analysis portion of this study was conducted in accordance with the County of San Diego Quality Assessment/Quality Control document.

QAPP Information Reference(s):

County of Orange. Quality Assurance/Quality Control Manual, February 2004 Bacteria specific

Line of Evidence (LOE) for Decision ID 16565, Total Coliform	Region 9
Loma Alta Slough

LOE ID:

27055

Pollutant:

Total Coliform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

186

Number of Exceedances:

Data and Information Type:

PWS pathogen monitoring (ambient water)

Data Used to Assess Water Quality:

Shoreline beach monitoring data was collected by the County of San Diego from June 2004 through December 2007. The number of samples collected for total coliform analysis was 186 with 34 monthly geomeans calculated. None of the geomeans exceeded the geomean 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 (SWRCB, 2005).

Single Sample Maximum: Total coliform density shall not exceed 10,000 per 100ml;

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 Pacific Ocean Shoreline, 500 feet north of Loma Alta outlet in the Loma Alta HA.

Temporal Representation:

Samples were collected weekly from January 2004 through December 2007.

Environmental Conditions:

QAPP Information:

Quality control for the bacteria analysis portion of this study was conducted in accordance with the County of San Diego's Quality beach monitoring program.

QAPP Information Reference(s):

County of San Diego, 2006. Department Public Health Laboratory, Quality Assurance Manual, December 2006


DECISION ID	6630	Region 9
Loma Alta Slough

Pollutant:	Eutrophic
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	List on 303(d) list (TMDL required list)(2006)
Revision Status	Original
Sources:	Nonpoint Source \| Unknown Point Source \| Urban Runoff/Storm Sewers
Expected TMDL Completion Date:	2015
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	303(d) listing decisions made prior to 2006 were not held in an assessment database. The Regional Boards will update this decision when new data and information become available and are assessed.

Regional Board Decision Recommendation:	No new data were assessed for 2008. The Regional Board will update this decision when new data and information become available and are assessed.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

USEPA Action (if applicable):	USEPA approved the listing of this water body as a water quality limited segment requiring a TMDL for this pollutant.

Line of Evidence (LOE) for Decision ID 6630, Eutrophic	Region 9
Loma Alta Slough

LOE ID:

4454

Pollutant:

Eutrophic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Marine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.

Data Reference:

Placeholder reference pre-2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Unspecified

Objective/Criterion Reference:

Placeholder reference pre-2006 303(d)

Evaluation Guideline:

Unspecified

Guideline Reference:

Placeholder reference pre-2006 303(d)

Spatial Representation:

Unspecified

Temporal Representation:

Unspecified

Environmental Conditions:

Unspecified

QAPP Information:

Unspecified

QAPP Information Reference(s):


DECISION ID	6633	Region 9
Loma Alta Slough

Pollutant:	Indicator Bacteria
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	List on 303(d) list (TMDL required list)(2006)
Revision Status	Original
Sources:	Unknown Nonpoint Source \| Unknown Point Source \| Urban Runoff/Storm Sewers
Expected TMDL Completion Date:	2015
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	303(d) listing decisions made prior to 2006 were not held in an assessment database. The Regional Boards will update this decision when new data and information become available and are assessed.

Regional Board Decision Recommendation:	No new data were assessed for 2008. The Regional Board will update this decision when new data and information become available and are assessed.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

USEPA Action (if applicable):	USEPA approved the listing of this water body as a water quality limited segment requiring a TMDL for this pollutant.

Line of Evidence (LOE) for Decision ID 6633, Indicator Bacteria	Region 9
Loma Alta Slough

LOE ID:

4455

Pollutant:

Indicator Bacteria

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.

Data Reference:

Placeholder reference pre-2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Unspecified

Objective/Criterion Reference:

Placeholder reference pre-2006 303(d)

Evaluation Guideline:

Unspecified

Guideline Reference:

Placeholder reference pre-2006 303(d)

Spatial Representation:

Unspecified

Temporal Representation:

Unspecified

Environmental Conditions:

Unspecified

QAPP Information:

Unspecified

QAPP Information Reference(s):