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, Tijuana HU, at the US Border
Water Body ID: CAC9111100020090505135528
Water Body Type: Coastal & Bay Shoreline
 
DECISION ID
16905
Region 9     
Pacific Ocean Shoreline, Tijuana HU, at the US Border
 
Pollutant: Enterococcus
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Sources: Urban Runoff/Storm Sewers
Expected TMDL Completion Date: 2021
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Regional Board Conclusion:
In 2006, 'Pacific Ocean Shoreline, Tijuana HU' was listed for Indicator Bacteria. For 2008, the 2006 Tijuana HU segment has been split into smaller segments and each represents an area near the sampling location of the data being assessed. 'Pacific Ocean Shoreline, Tijuana HU, at the US Border' is one of the sampling locations for Pacific Ocean Shoreline, Tijuana HU, and is considered to be part of the original listing.

For this 2008 assessment, the Regional Board has chosen to replace the 'indicator bacteria' listing with separate assessments of the specific indicator bacteria, such as total coliform, fecal coliform, and enterococcus, for removal or non-removal from the 303(d) list.

In LOE 29397, the Regional Board calculated exceedances for samples taken only during storm events. This information was not used in determining listing decisions, but is of interest to the Regional Board and has been included as additional anecdotal information.

This pollutant is being considered for removal from the section 303(d) list under section 4.3 of the Listing Policy. Under this section 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. Twenty-seven of the 192 samples exceeded the Basin Plan single sample maximum water quality objective for enterococcus.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for removing this water segment-pollutant combination from the section 303(d) list.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Twenty-seven of the 192 samples exceeded the Basin Plan single sample maximum water quality objective for enterococcus and this does not exceed the allowable frequency listed in Table 4.2 of the Listing Policy.
4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

.
State Board Review and Conclusion:
The San Diego Regional Board staff requested the State Water Board staff to conduct an additional evaluation of the Regional Board's AB411 beach data in the Region's transmittal letter to the State Board. State Water Board staff assessed the dry weather data for this beach and revised the recommendation to be Do Not Delist based on section 3.3 and 4.3 of the Listing Policy. The revised recommendation is as follows:

In 2006, 'Pacific Ocean Shoreline, Tijuana HU' was listed for Indicator Bacteria. For 2008, the 2006 Tijuana HU segment has been split into smaller segments and each represents an area near the sampling location of the data being assessed. 'Pacific Ocean Shoreline, Tijuana HU, at the US Border' is one of the sampling locations for Pacific Ocean Shoreline, Tijuana HU, and is considered to be part of the original listing.

For this 2008 assessment the Regional Board has chosen to replace the 'indicator bacteria' listing with separate assessments of the specific indicator bacteria, such as total coliform, fecal coliform, and enterococcus, for removal or non-removal from the 303(d) list.

In LOE 29397 the Regional Board calculated exceedances for samples taken only during storm events. This information was not used in determining listing decisions, but is of interest to the Regional Board and has been included as additional anecdotal information.

This pollutant is being considered for removal from the section 303(d) list under section 4.3 of the Listing Policy. Under this section 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. Twenty-seven of the 192 samples exceeded the Basin Plan single sample maximum 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 4 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. Eighteen of 179 dry weather single samples exceeded the criteria for recreational use and this does exceed the allowable limit based on the application of a four percent exceedance percentage (AB411). 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.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the section 303(d) list.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Twenty-seven of the 192 samples exceeded the Basin Plan single sample maximum water quality objective for enterococcus and this does not exceed the allowable frequency listed in Table 4.2 of the Policy.
4. Eighteen of 179 dry weather single samples exceeded the criteria for recreational use and this exceeds the allowable limit based on the application of a four percent exceedance percentage (AB411) to section 4.3 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 4.3 of the Policy.
6. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be removed from the section 303(d) list because applicable water quality standards for the pollutant are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation: .
State Board Review and Conclusion:
The San Diego Regional Board staff requested the State Water Board staff to conduct an additional evaluation of the Regional Board's AB411 beach data in the Region's transmittal letter to the State Board. State Water Board staff assessed the dry weather data for this beach and revised the recommendation to be Do Not Delist based on section 3.3 and 4.3 of the Listing Policy. The revised recommendation is as follows:

In 2006, 'Pacific Ocean Shoreline, Tijuana HU' was listed for Indicator Bacteria. For 2008, the 2006 Tijuana HU segment has been split into smaller segments and each represents an area near the sampling location of the data being assessed. 'Pacific Ocean Shoreline, Tijuana HU, at the US Border' is one of the sampling locations for Pacific Ocean Shoreline, Tijuana HU, and is considered to be part of the original listing.

For this 2008 assessment the Regional Board has chosen to replace the 'indicator bacteria' listing with separate assessments of the specific indicator bacteria, such as total coliform, fecal coliform, and enterococcus, for removal or non-removal from the 303(d) list.

In LOE 29397 the Regional Board calculated exceedances for samples taken only during storm events. This information was not used in determining listing decisions, but is of interest to the Regional Board and has been included as additional anecdotal information.

This pollutant is being considered for removal from the section 303(d) list under section 4.3 of the Listing Policy. Under this section 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. Twenty-seven of the 192 samples exceeded the Basin Plan single sample maximum 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 4 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. Eighteen of 179 dry weather single samples exceeded the criteria for recreational use and this does exceed the allowable limit based on the application of a four percent exceedance percentage (AB411). 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.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the section 303(d) list.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Twenty-seven of the 192 samples exceeded the Basin Plan single sample maximum water quality objective for enterococcus and this does not exceed the allowable frequency listed in Table 4.2 of the Policy.
4. Eighteen of 179 dry weather single samples exceeded the criteria for recreational use and this exceeds the allowable limit based on the application of a four percent exceedance percentage (AB411) to section 4.3 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 4.3 of the Policy.
6. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the following changes to the decision:
The water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
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 16905, Enterococcus
Region 9     
Pacific Ocean Shoreline, Tijuana HU, at the US Border
 
LOE ID: 29400
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 45
Number of Exceedances: 7
 
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 192 single samples were collected with 45 monthly geomeans calculated. Seven of the 45 geomeans exceeded the geomean water quality objective.
Data Reference: Department of Environmental Health, Ocean & Bay Recreational Water Quality Program, 2007. AB 411 monitoring data 1999 to 2007
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Geomean: Enterococcus density shall not exceed 35 per 100 ml.

Single Sample Maximum: Enterococcus density shall not exceed 104 per 100 ml (SWRCB, 2005).
Objective/Criterion Reference: Water Quality Control Plan Ocean Waters of California. California Ocean Plan 2005. Sacramento, CA: State Water Resources Control Board, California Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at Border Fence North Side, Imperial Beach, California. Station identification number is IB-010.
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 16905, Enterococcus
Region 9     
Pacific Ocean Shoreline, Tijuana HU, at the US Border
 
LOE ID: 31119
 
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 April 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 Border Fence North Side, Imperial Beach, California. Station identification number is IB-010.
Temporal Representation: Samples were collected from April 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 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 16905, Enterococcus
Region 9     
Pacific Ocean Shoreline, Tijuana HU, at the US Border
 
LOE ID: 30356
 
Pollutant: Indicator Bacteria
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 0
Number of Exceedances: 0
 
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.

For the 2008 assessment , the 2006 listed coastline 'Pacific Ocean Shoreline, Tijuana HU' was split into smaller segments and each represents an area near the sampling location of the data being assessed. This segment 'Pacific Ocean Shoreline, Tijuana HU, at the US Border' is one of the sampling locations. This LOE is a copy of the 2006 listing placeholder LOE for Pacific Ocean Shoreline, Tijuana HU and is considered by the Regional Board to be applicable to this more specific segment formed from the split.
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:
Guideline Reference:
 
Spatial Representation:
Temporal Representation:
Environmental Conditions:
QAPP Information: Unspecified
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 16905, Enterococcus
Region 9     
Pacific Ocean Shoreline, Tijuana HU, at the US Border
 
LOE ID: 29397
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 13
Number of Exceedances: 9
 
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 192 single samples were collected with 13 samples correlated with a storm event. Nine of the 13 samples exceeded the single sample water quality objective. This information will not be used in determining a listing decision, but is of interest to the Regional Board and has been included here as additional anecdotal information.
Data Reference: National Weather Service Forecast Office, San Diego, California, Chronological Regional Temperature and Precipitation Listings by Station
  Department of Environmental Health, Ocean & Bay Recreational Water Quality Program, 2007. AB 411 monitoring data 1999 to 2007
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Geomean: Enterococcus density shall not exceed 35 per 100 ml.

Single Sample Maximum: Enterococcus density shall not exceed 104 per 100 ml (SWRCB, 2005).

Comparisons are also made for days with matching bacteria and storm event data. A storm event is 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 Border Fence North Side, Imperial Beach, California. Station identification number is IB-010.
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 16905, Enterococcus
Region 9     
Pacific Ocean Shoreline, Tijuana HU, at the US Border
 
LOE ID: 29396
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 192
Number of Exceedances: 27
 
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 192 single samples were collected with 27 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 Border Fence North Side, Imperial Beach, California. Station identification number is IB-010.
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 16905, Enterococcus
Region 9     
Pacific Ocean Shoreline, Tijuana HU, at the US Border
 
LOE ID: 30670
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 179
Number of Exceedances: 18
 
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 192 single samples were collected of which 179 are dry weather (AB411) samples with 18 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 Border Fence North Side, Imperial Beach, California. Station identification number is IB-010.
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 16905, Enterococcus
Region 9     
Pacific Ocean Shoreline, Tijuana HU, at the US Border
 
LOE ID: 29441
 
Pollutant: Indicator Bacteria
LOE Subgroup: Health Advisories
Matrix: -N/A
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 2555
Number of Exceedances: 40
 
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 forty beach advisory days for this section of shoreline. Bacteriological samples are collected on a weekly basis at ocean and bay locations in San Diego County. When a bacteriological sample exceeds water quality standards, signs are posted indicating that an advisory for 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 - December 2007. Data used was the number of days the beach was advisories were issued when the ocean or bay failed to meet the bacteriological standards.
Data Reference: Department of Environmental Health, Land and Water Quality Division. San Diego County Beach Closure and Advisory Report
 
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 North Side of the Border Fence, Imperial Beach, California.
Temporal Representation: The beach advisory covers the time frame of January January 2001 to December 2007.
Environmental Conditions:
QAPP Information: Samples were collected in compliance with County of San Diego's Quality Assessment/Quality Control document
QAPP Information Reference(s): County of San Diego, 2006. Department Public Health Laboratory, Quality Assurance Manual, December 2006
 
 
DECISION ID
16906
Region 9     
Pacific Ocean Shoreline, Tijuana HU, at the US Border
 
Pollutant: Fecal Coliform
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Sources: Urban Runoff/Storm Sewers
Expected TMDL Completion Date: 2021
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: In 2006, 'Pacific Ocean Shoreline, Tijuana HU' was listed for Indicator Bacteria. For 2008, the 2006 Tijuana HU segment has been split into smaller segments and each represents an area near the sampling location of the data being assessed. 'Pacific Ocean Shoreline, Tijuana HU, at the US Border' is one of the sampling locations for Pacific Ocean Shoreline, Tijuana HU, and is considered to be part of the original listing.

For this 2008 assessment, the Regional Board has chosen to replace the 'indicator bacteria' listing with separate assessments of the specific indicator bacteria, such as total coliform, fecal coliform, and enterococcus, for removal or non-removal from the 303(d) list.

This pollutant is being considered for removal from the section 303(d) list under section 4.3 of the Listing Policy. Under this section 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. Twenty-four of the 192 samples exceeded the Basin Plan single sample maximum water quality objective for fecal coliform.

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. Twenty of 179 single samples a and this exceeds the allowable limit (at a four percent exceedance percentage - AB411) in section 4.3 of the Listing Policy. 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 4.3 of the Listing Policy.

In LOE 29395, the Regional Board calculated exceedances for samples taken only during storm events. This information was not used in determining listing decisions, but is of interest to the Regional Board and has been included as additional anecdotal information.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for removing this water segment-pollutant combination from the section 303(d) list.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Twenty-four of the 192 samples exceeded the Basin Plan single sample maximum water quality objective for fecal coliform and this does not exceed the allowable frequency listed in Table 4.2 of the Listing Policy.
4. Twenty of 179 dry weather single samples exceeded the total coliform criteria for recreational use and this exceeds the allowable limit (at a four percent exceedance percentage - AB411) in section 4.3 of the Listing Policy.
5. One of 25 dry weather geometric mean calculations 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 4.3 of the Listing Policy.
6. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be removed from the section 303(d) list because applicable water quality standards for the pollutant are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the following changes to the decision:
The water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
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 16906, Fecal Coliform
Region 9     
Pacific Ocean Shoreline, Tijuana HU, at the US Border
 
LOE ID: 29394
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 192
Number of Exceedances: 24
 
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 192 single samples were collected with 24 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 Border Fence North Side, Imperial Beach, California. Station identification number is IB-010.
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 16906, Fecal Coliform
Region 9     
Pacific Ocean Shoreline, Tijuana HU, at the US Border
 
LOE ID: 29395
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 13
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 192 single samples were collected with 13 samples correlated with a storm event. Four of the 13 samples exceeded the single sample water quality objective. This information will not be used in determining a listing decision, but is of interest to the Regional Board and has been included here as additional anecdotal information.
Data Reference: National Weather Service Forecast Office, San Diego, California, Chronological Regional Temperature and Precipitation Listings by Station
  Department of Environmental Health, Ocean & Bay Recreational Water Quality Program, 2007. AB 411 monitoring data 1999 to 2007
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Geomean; 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).

Comparisons are also made only 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 Border Fence North Side, Imperial Beach, California. Station identification number is IB-010.
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 16906, Fecal Coliform
Region 9     
Pacific Ocean Shoreline, Tijuana HU, at the US Border
 
LOE ID: 29399
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 45
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 192 single samples were collected and 45 geomeans calculated. Four of the 45 geomeans exceeded the geomean water quality objective.
Data Reference: Department of Environmental Health, Ocean & Bay Recreational Water Quality Program, 2007. AB 411 monitoring data 1999 to 2007
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Geomean; 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 Border Fence North Side, Imperial Beach, California. Station identification number is IB-010.
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 16906, Fecal Coliform
Region 9     
Pacific Ocean Shoreline, Tijuana HU, at the US Border
 
LOE ID: 30356
 
Pollutant: Indicator Bacteria
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 0
Number of Exceedances: 0
 
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.

For the 2008 assessment , the 2006 listed coastline 'Pacific Ocean Shoreline, Tijuana HU' was split into smaller segments and each represents an area near the sampling location of the data being assessed. This segment 'Pacific Ocean Shoreline, Tijuana HU, at the US Border' is one of the sampling locations. This LOE is a copy of the 2006 listing placeholder LOE for Pacific Ocean Shoreline, Tijuana HU and is considered by the Regional Board to be applicable to this more specific segment formed from the split.
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:
Guideline Reference:
 
Spatial Representation:
Temporal Representation:
Environmental Conditions:
QAPP Information: Unspecified
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 16906, Fecal Coliform
Region 9     
Pacific Ocean Shoreline, Tijuana HU, at the US Border
 
LOE ID: 31120
 
Pollutant: Fecal Coliform
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 April 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; 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 Border Fence North Side, Imperial Beach, California. Station identification number is IB-010.
Temporal Representation: Samples were collected from April 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 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 16906, Fecal Coliform
Region 9     
Pacific Ocean Shoreline, Tijuana HU, at the US Border
 
LOE ID: 30770
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 179
Number of Exceedances: 20
 
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 192 single samples were collected of which 179 are dry weather (AB411) samples with 20 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 Border Fence North Side, Imperial Beach, California. Station identification number is IB-010.
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 16906, Fecal Coliform
Region 9     
Pacific Ocean Shoreline, Tijuana HU, at the US Border
 
LOE ID: 29441
 
Pollutant: Indicator Bacteria
LOE Subgroup: Health Advisories
Matrix: -N/A
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 2555
Number of Exceedances: 40
 
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 forty beach advisory days for this section of shoreline. Bacteriological samples are collected on a weekly basis at ocean and bay locations in San Diego County. When a bacteriological sample exceeds water quality standards, signs are posted indicating that an advisory for 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 - December 2007. Data used was the number of days the beach was advisories were issued when the ocean or bay failed to meet the bacteriological standards.
Data Reference: Department of Environmental Health, Land and Water Quality Division. San Diego County Beach Closure and Advisory Report
 
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 North Side of the Border Fence, Imperial Beach, California.
Temporal Representation: The beach advisory covers the time frame of January January 2001 to December 2007.
Environmental Conditions:
QAPP Information: Samples were collected in compliance with County of San Diego's Quality Assessment/Quality Control document
QAPP Information Reference(s): County of San Diego, 2006. Department Public Health Laboratory, Quality Assurance Manual, December 2006
 
 
DECISION ID
16908
Region 9     
Pacific Ocean Shoreline, Tijuana HU, at the US Border
 
Pollutant: Total Coliform
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Sources: Natural Sources | Source Unknown | Unknown Nonpoint Source | Urban Runoff/Storm Sewers
Expected TMDL Completion Date: 2019
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: In 2006, 'Pacific Ocean Shoreline, Tijuana HU' was listed for Indicator Bacteria. For 2008, the 2006 Tijuana HU segment has been split into smaller segments and each represents an area near the sampling location of the data being assessed. 'Pacific Ocean Shoreline, Tijuana HU, at the US Border' is one of the sampling locations for Pacific Ocean Shoreline, Tijuana HU, and is considered to be part of the original listing.

For this 2008 assessment, the Regional Board has chosen to replace the 'indicator bacteria' listing with separate assessments of the specific indicator bacteria, such as total coliform, fecal coliform, and enterococcus, for removal or non-removal from the 303(d) list.

This pollutant is being considered for removal from the section 303(d) list under section 4.3 of the Listing Policy. Under this section 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. Sixty of the 192 samples exceed the Basin Plan single sample maximum shellfish harvesting water quality objective for total coliform.

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. Twenty-three of 179 dry weather single samples exceeded the criteria for recreational use and this does exceed the allowable limit based on the application of a four percent exceedance percentage (AB411) to section 4.3 of the Listing Policy. 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 4.3 of the Listing Policy.

In LOEs 29391 and 29393, the Regional Board calculated exceedances for samples taken only during storm events. This information was not used in determining listing decisions, but is of interest to the Regional Board and has been included as additional anecdotal information.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the section 303(d) list.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Sixty of the 192 samples exceed the Basin Plan single sample maximum shellfish harvesting water quality objective for total coliform and this exceeds the allowable frequency listed in Table 4.2 of the Listing Policy.
4. Twenty-three of 179 dry weather single samples exceeded the criteria for recreational use and this does exceed the allowable limit based on the application of a four percent exceedance percentage (AB411) to section 4.3 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 4.3 of the Listing Policy.
6. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are 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 removed from the section 303(d) list because applicable water quality standards for the pollutant are 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 removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
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 16908, Total Coliform
Region 9     
Pacific Ocean Shoreline, Tijuana HU, at the US Border
 
LOE ID: 29390
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Shellfish Harvesting
 
Number of Samples: 192
Number of Exceedances: 60
 
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 192 single samples were collected with 60 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). 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
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 Border Fence North Side, Imperial Beach, California. Station identification number is IB-010.
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 16908, Total Coliform
Region 9     
Pacific Ocean Shoreline, Tijuana HU, at the US Border
 
LOE ID: 29398
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 45
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 192 single samples were collected with 45 monthly geomeans calculated. Four of the 45 geomeans exceeded the geomean water quality objective.
Data Reference: Department of Environmental Health, Ocean & Bay Recreational Water Quality Program, 2007. AB 411 monitoring data 1999 to 2007
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Geomean: Total coliform density shall not exceed 1,000 per 100ml;

Single Sample Maximum: Total coliform density shall not exceed 10,000 per 100ml (SWRCB, 2005).
Objective/Criterion Reference: Water Quality Control Plan Ocean Waters of California. California Ocean Plan 2005. Sacramento, CA: State Water Resources Control Board, California Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at Border Fence North Side, Imperial Beach, California. Station identification number is IB-010.
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 16908, Total Coliform
Region 9     
Pacific Ocean Shoreline, Tijuana HU, at the US Border
 
LOE ID: 29393
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 13
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 192 single samples were collected with 13 samples correlated with a storm event. Five of the 13 samples exceeded the single sample water quality objective. This information will not be used in determining a listing decision, but is of interest to the Regional Board and has been included here as additional anecdotal information.
Data Reference: National Weather Service Forecast Office, San Diego, California, Chronological Regional Temperature and Precipitation Listings by Station
  Department of Environmental Health, Ocean & Bay Recreational Water Quality Program, 2007. AB 411 monitoring data 1999 to 2007
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Geomean: Total coliform density shall not exceed 1,000 per 100ml;

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

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.
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 Border Fence North Side, Imperial Beach, California. Station identification number is IB-010.
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 16908, Total Coliform
Region 9     
Pacific Ocean Shoreline, Tijuana HU, at the US Border
 
LOE ID: 29392
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 192
Number of Exceedances: 28
 
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 192 single samples were collected with 28 samples exceeding the single sample water quality objective.
Data Reference: National Weather Service Forecast Office, San Diego, California, Chronological Regional Temperature and Precipitation Listings by Station
  Department of Environmental Health, Ocean & Bay Recreational Water Quality Program, 2007. AB 411 monitoring data 1999 to 2007
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Geomean: Total coliform density shall not exceed 1,000 per 100ml;

Single Sample Maximum: Total coliform density shall not exceed 10,000 per 100ml (SWRCB, 2005).
Objective/Criterion Reference: Water Quality Control Plan Ocean Waters of California. California Ocean Plan 2005. Sacramento, CA: State Water Resources Control Board, California Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at Border Fence North Side, Imperial Beach, California. Station identification number is IB-010.
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 16908, Total Coliform
Region 9     
Pacific Ocean Shoreline, Tijuana HU, at the US Border
 
LOE ID: 29441
 
Pollutant: Indicator Bacteria
LOE Subgroup: Health Advisories
Matrix: -N/A
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 2555
Number of Exceedances: 40
 
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 forty beach advisory days for this section of shoreline. Bacteriological samples are collected on a weekly basis at ocean and bay locations in San Diego County. When a bacteriological sample exceeds water quality standards, signs are posted indicating that an advisory for 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 - December 2007. Data used was the number of days the beach was advisories were issued when the ocean or bay failed to meet the bacteriological standards.
Data Reference: Department of Environmental Health, Land and Water Quality Division. San Diego County Beach Closure and Advisory Report
 
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 North Side of the Border Fence, Imperial Beach, California.
Temporal Representation: The beach advisory covers the time frame of January January 2001 to December 2007.
Environmental Conditions:
QAPP Information: Samples were collected in compliance with County of San Diego's Quality Assessment/Quality Control document
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 16908, Total Coliform
Region 9     
Pacific Ocean Shoreline, Tijuana HU, at the US Border
 
LOE ID: 30356
 
Pollutant: Indicator Bacteria
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 0
Number of Exceedances: 0
 
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.

For the 2008 assessment , the 2006 listed coastline 'Pacific Ocean Shoreline, Tijuana HU' was split into smaller segments and each represents an area near the sampling location of the data being assessed. This segment 'Pacific Ocean Shoreline, Tijuana HU, at the US Border' is one of the sampling locations. This LOE is a copy of the 2006 listing placeholder LOE for Pacific Ocean Shoreline, Tijuana HU and is considered by the Regional Board to be applicable to this more specific segment formed from the split.
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:
Guideline Reference:
 
Spatial Representation:
Temporal Representation:
Environmental Conditions:
QAPP Information: Unspecified
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 16908, Total Coliform
Region 9     
Pacific Ocean Shoreline, Tijuana HU, at the US Border
 
LOE ID: 30877
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 179
Number of Exceedances: 23
 
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 192 single samples were collected of which 179 are dry weather (AB411) samples with 23 of those samples exceeding the single sample water quality objective.
Data Reference: National Weather Service Forecast Office, San Diego, California, Chronological Regional Temperature and Precipitation Listings by Station
  Department of Environmental Health, Ocean & Bay Recreational Water Quality Program, 2007. AB 411 monitoring data 1999 to 2007
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Geomean: Total coliform density shall not exceed 1,000 per 100ml;

Single Sample Maximum: Total coliform density shall not exceed 10,000 per 100ml (SWRCB, 2005).
Objective/Criterion Reference: Water Quality Control Plan Ocean Waters of California. California Ocean Plan 2005. Sacramento, CA: State Water Resources Control Board, California Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at Border Fence North Side, Imperial Beach, California. Station identification number is IB-010.
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 16908, Total Coliform
Region 9     
Pacific Ocean Shoreline, Tijuana HU, at the US Border
 
LOE ID: 29391
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Shellfish Harvesting
 
Number of Samples: 13
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 192 single samples were collected with 13 samples correlated with a storm event. Eleven of the 13 samples exceeded the single sample water quality objective. This information will not be used in determining a listing decision, but is of interest to the Regional Board and has been included here as additional anecdotal information.
Data Reference: National Weather Service Forecast Office, San Diego, California, Chronological Regional Temperature and Precipitation Listings by Station
  Department of Environmental Health, Ocean & Bay Recreational Water Quality Program, 2007. AB 411 monitoring data 1999 to 2007
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: 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 Border Fence North Side, Imperial Beach, California. Station identification number is IB-010.
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 16908, Total Coliform
Region 9     
Pacific Ocean Shoreline, Tijuana HU, at the US Border
 
LOE ID: 31121
 
Pollutant: Total Coliform
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 April 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: 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 Border Fence North Side, Imperial Beach, California. Station identification number is IB-010.
Temporal Representation: Samples were collected from April 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 Orange. Quality Assurance/Quality Control Manual, February 2004 Bacteria specific
  County of San Diego, 2006. Department Public Health Laboratory, Quality Assurance Manual, December 2006