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, San Joaquin Hills HSA, at Emerald Bay Beach
Water Body ID: CAC9011100020091022114130
Water Body Type: Coastal & Bay Shoreline
 
DECISION ID
17707
Region 9     
Pacific Ocean Shoreline, San Joaquin Hills HSA, at Emerald Bay Beach
 
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.

In 2006, 'Pacific Ocean Shoreline, San Joaquin Hills HSA' was listed for Indicator Bacteria. For 2008, the 2006 San Joaquin Hills HSA segment has been split into smaller segments and each represents an area near the sampling location of
the data being assessed. 'Pacific Ocean Shoreline, San Joaquin Hills HSA, at Emerald Bay Beach' is one of the sampling locations for Pacific Ocean Shoreline, San Joaquin Hills HSA, 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.

Four lines of evidence are available in the administrative record to assess this pollutant. Six of 438 samples exceeded the water quality objective for enterococcus.

The coastal beach at this water segment is identified as an AB411 beach. To comply with the requirements of AB411 the dry weather data collected during the time frame of April 1st to October 31st is assessed using a four percent exceedance percentage, as described in section 3.3 and 4.3 of the Listing Policy. An assessment for dry weather geometric mean calculation was conducted and there is one additional line of evidence available in the administrative record. One of 56 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.

In LOE 30426, 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 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. Six of 438 samples exceeded the enterococcus water quality objective and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy.
4. One of 56 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 17707, Enterococcus
Region 9     
Pacific Ocean Shoreline, San Joaquin Hills HSA, at Emerald Bay Beach
 
LOE ID: 30426
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 49
Number of Exceedances: 2
 
Data and Information Type: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: Beach monitoring data was collected by the County of Orange from January 1999 through December 2007. A total of 438 single samples were collected. Between March 2002 and December 2007, 49 samples were correlated with a storm event. Of the 49 samples, only two 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: Ocean Bacteriological Data Evaluation for City of Laguna Beach, 1999 through 2006, Final Report
  National Weather Service Forecast Office, San Diego, California, Chronological Regional Temperature and Precipitation Listings by Station
 
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 Emerald Bay Beach, station id OLB 10, in the San Joaquin HSA. Lat/Long: 33.55099/-117.80801.
Temporal Representation: Samples were collected weekly from January 1999 through December 2007; however, rainfall data is only available from March 2002 through December 2007.
Environmental Conditions: Comparisons were made for all data and data associated with storm events. A storm event was defined as 0.2 inches of rainfall within a 72 hour period.

Analyzing only storm water bacteria data is important because the majority of beach monitoring data covers the months of April through October. The data may not capture the full impacts of seasonal storm events and high bacteria levels due to storm water runoff because much of the wet season for Southern California occurs in November through March.
QAPP Information: Quality control for the bacteria analysis portion of this study was conducted in accordance with the County of Orange 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 17707, Enterococcus
Region 9     
Pacific Ocean Shoreline, San Joaquin Hills HSA, at Emerald Bay Beach
 
LOE ID: 30421
 
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, San Joaquin Hills HSA' was split into smaller segments and each represents an area near the sampling location of the data being assessed. This segment 'Pacific Ocean Shoreline, San Joaquin Hills HSA, at Emerald Bay Beach' is one of the sampling locations. This LOE is a copy of the 2006 listing placeholder LOE for Pacific Ocean Shoreline, San Joaquin Hills HSA 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 17707, Enterococcus
Region 9     
Pacific Ocean Shoreline, San Joaquin Hills HSA, at Emerald Bay Beach
 
LOE ID: 30439
 
Pollutant: Indicator Bacteria
LOE Subgroup: Health Advisories
Matrix: -N/A
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 1460
Number of Exceedances: 4
 
Data and Information Type: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: For the period from January 2004 to December 2007, there were and 4 beach postings days for this section of shoreline. Bacteriological samples are collected on a weekly basis at approximately 150 ocean and bay location in Orange County. When a bacteriological sample exceeds water quality standards, signs are posted indicating that waters have exceeded public health standards.

Data and information on the number of beach posting were summarized by the County of Orange in their Annual Ocean and Bay Water Quality Report, March 2007. The reporting period was from January 2004 -December 2007. Data used was the number of days the beach was posting when the ocean or bay failed to meet the bacteriological standards.
Data Reference: County of Orange. March 2007. Annual Ocean and Bay Water Quality Report, 2006
 
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:
 
Spatial Representation: Bacteriological monitoring samples was collected at Emerald Bay beach shoreline.
Temporal Representation: The beach posting covers the time frame of January 2004 -December 2007.
Environmental Conditions:
QAPP Information: Samples were collected in compliance with County of Orange's Quality Assessment/Quality Control document (County of Orange, 2004).
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 17707, Enterococcus
Region 9     
Pacific Ocean Shoreline, San Joaquin Hills HSA, at Emerald Bay Beach
 
LOE ID: 31109
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 56
Number of Exceedances: 1
 
Data and Information Type: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: Orange County collected Beach monitoring data within the time period from January 1999 through December 2006.
A total of 56 monthly geomeans were calculated for data collected during the time frame of April 1st to October 31st (AB411 data) within the aforementioned time period. Of the 56 geomeans one exceeded the geomean water quality objective.
Data Reference: Ocean Bacteriological Data Evaluation for City of Laguna Beach, 1999 through 2006, Final Report
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The 30-day Geometric mean for enterococcus density shall not exceed 35 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 Emerald Bay Beach, station id OLB 10, in the San Joaquin HSA. Lat/Long: 33.55099/-117.80801.
Temporal Representation: Samples were collected at least once a week within the time period from January 1999 through December 2006.
The data assessed is AB411 data which is data collected during the time frame of April 1st to October 31st (summer months) within the aforementioned time period.
Environmental Conditions:
QAPP Information: Quality control for the bacteria analysis portion of this study was conducted in accordance with the County of Orange 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 17707, Enterococcus
Region 9     
Pacific Ocean Shoreline, San Joaquin Hills HSA, at Emerald Bay Beach
 
LOE ID: 30428
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 438
Number of Exceedances: 6
 
Data and Information Type: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: Beach monitoring data was collected by the County of Orange from January 1999 through December 2007. A total of 438 single samples were collected with six samples exceeding the single sample water quality objective.
Data Reference: Ocean Bacteriological Data Evaluation for City of Laguna Beach, 1999 through 2006, Final Report
 
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 Emerald Bay Beach, station id OLB 10, in the San Joaquin HSA. Lat/Long: 33.55099/-117.80801.
Temporal Representation: Samples were collected weekly from January 1999 through December 2007; however, rainfall data is only available from March 2002 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 Orange 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 17707, Enterococcus
Region 9     
Pacific Ocean Shoreline, San Joaquin Hills HSA, at Emerald Bay Beach
 
LOE ID: 30429
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 106
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 Orange from January 1999 through December 2007. A total of 438 single samples were collected and 106 monthly geomeans calculated. Of the 106 geomeans, only one geomean exceeded the geomean water quality objective.
Data Reference: Ocean Bacteriological Data Evaluation for City of Laguna Beach, 1999 through 2006, Final Report
 
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 Emerald Bay Beach, station id OLB 10, in the San Joaquin HSA. Lat/Long: 33.55099/-117.80801.
Temporal Representation: Samples were collected weekly from January 1999 through December 2007; however, rainfall data is only available from March 2002 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 Orange Quality Assessment/Quality Control document.
QAPP Information Reference(s): County of Orange. Quality Assurance/Quality Control Manual, February 2004 Bacteria specific
 
 
DECISION ID
17708
Region 9     
Pacific Ocean Shoreline, San Joaquin Hills HSA, at Emerald Bay Beach
 
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: In 2006, 'Pacific Ocean Shoreline, San Joaquin Hills HSA' was listed for Indicator Bacteria. For 2008, the 2006 San Joaquin Hills HSA segment has been split into smaller segments and each represents an area near the sampling location of the data being assessed. 'Pacific Ocean Shoreline, San Joaquin Hills HSA, at Emerald Bay Beach' is one of the sampling locations for Pacific Ocean Shoreline, San Joaquin Hills HSA, 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 listing under section 3.3 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. Two of 445 samples exceeded the 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 geometric mean calculation was conducted and there is one additional line of evidence available in the administrative record. Zero of 56 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.

In LOE 30435, 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 placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Two of 445 samples exceeded the fecal coliform water quality objective and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy.
4. Zero of 56 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 17708, Fecal Coliform
Region 9     
Pacific Ocean Shoreline, San Joaquin Hills HSA, at Emerald Bay Beach
 
LOE ID: 30439
 
Pollutant: Indicator Bacteria
LOE Subgroup: Health Advisories
Matrix: -N/A
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 1460
Number of Exceedances: 4
 
Data and Information Type: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: For the period from January 2004 to December 2007, there were and 4 beach postings days for this section of shoreline. Bacteriological samples are collected on a weekly basis at approximately 150 ocean and bay location in Orange County. When a bacteriological sample exceeds water quality standards, signs are posted indicating that waters have exceeded public health standards.

Data and information on the number of beach posting were summarized by the County of Orange in their Annual Ocean and Bay Water Quality Report, March 2007. The reporting period was from January 2004 -December 2007. Data used was the number of days the beach was posting when the ocean or bay failed to meet the bacteriological standards.
Data Reference: County of Orange. March 2007. Annual Ocean and Bay Water Quality Report, 2006
 
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:
 
Spatial Representation: Bacteriological monitoring samples was collected at Emerald Bay beach shoreline.
Temporal Representation: The beach posting covers the time frame of January 2004 -December 2007.
Environmental Conditions:
QAPP Information: Samples were collected in compliance with County of Orange's Quality Assessment/Quality Control document (County of Orange, 2004).
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 17708, Fecal Coliform
Region 9     
Pacific Ocean Shoreline, San Joaquin Hills HSA, at Emerald Bay Beach
 
LOE ID: 31108
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 56
Number of Exceedances: 0
 
Data and Information Type: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: Orange County collected Beach monitoring data within the time period from January 1999 through December 2006.
A total of 56 monthly geomeans were calculated for data collected during the time frame of April 1st to October 31st (AB411 data) within the aforementioned time period. Of the 56 geomeans zero exceeded the geomean water quality objective.
Data Reference: Ocean Bacteriological Data Evaluation for City of Laguna Beach, 1999 through 2006, Final Report
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The 30-day Geometric Mean for fecal coliform density shall not exceed 200 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 Emerald Bay Beach, station id OLB 10, in the San Joaquin HSA. Lat/Long: 33.55099/-117.80801.
Temporal Representation: Samples were collected at least once a week within the time period from January 1999 through December 2006.
The data assessed is AB411 data which is data collected during the time frame of April 1st to October 31st (summer months) within the aforementioned time period.
Environmental Conditions:
QAPP Information: Quality control for the bacteria analysis portion of this study was conducted in accordance with the County of Orange 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 17708, Fecal Coliform
Region 9     
Pacific Ocean Shoreline, San Joaquin Hills HSA, at Emerald Bay Beach
 
LOE ID: 30432
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 445
Number of Exceedances: 2
 
Data and Information Type: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: Beach monitoring data was collected by the County of Orange from January 1999 through December 2007. A total of 445 single samples were collected with two exceeding the single sample water quality objective.
Data Reference: Ocean Bacteriological Data Evaluation for City of Laguna Beach, 1999 through 2006, Final Report
 
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 Emerald Bay Beach, station id OLB 10, in the San Joaquin HSA. Lat/Long: 33.55099/-117.80801.
Temporal Representation: Samples were collected weekly from January 1999 through December 2007; however, rainfall data is only available from March 2002 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 Orange Quality Assessment/Quality Control document.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 17708, Fecal Coliform
Region 9     
Pacific Ocean Shoreline, San Joaquin Hills HSA, at Emerald Bay Beach
 
LOE ID: 30433
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 107
Number of Exceedances: 0
 
Data and Information Type: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: Beach monitoring data was collected by the County of Orange from January 1999 through December 2007. A total of 445 single samples were collected with 107 monthly geomeans calculated. None of the 107 geomeans exceeded the geomean water quality objective.
Data Reference: Ocean Bacteriological Data Evaluation for City of Laguna Beach, 1999 through 2006, Final Report
 
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 Emerald Bay Beach, station id OLB 10, in the San Joaquin HSA. Lat/Long: 33.55099/-117.80801.
Temporal Representation: Samples were collected weekly from January 1999 through December 2007; however, rainfall data is only available from March 2002 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 Orange 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 17708, Fecal Coliform
Region 9     
Pacific Ocean Shoreline, San Joaquin Hills HSA, at Emerald Bay Beach
 
LOE ID: 30421
 
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, San Joaquin Hills HSA' was split into smaller segments and each represents an area near the sampling location of the data being assessed. This segment 'Pacific Ocean Shoreline, San Joaquin Hills HSA, at Emerald Bay Beach' is one of the sampling locations. This LOE is a copy of the 2006 listing placeholder LOE for Pacific Ocean Shoreline, San Joaquin Hills HSA 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 17708, Fecal Coliform
Region 9     
Pacific Ocean Shoreline, San Joaquin Hills HSA, at Emerald Bay Beach
 
LOE ID: 30435
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 49
Number of Exceedances: 0
 
Data and Information Type: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: Beach monitoring data was collected by the County of Orange from January 1999 through December 2007. A total of 445 single samples were collected. Between March 2002 and December 2007 49 samples were correlated with a storm event. None of the 49 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: Ocean Bacteriological Data Evaluation for City of Laguna Beach, 1999 through 2006, Final Report
  National Weather Service Forecast Office, San Diego, California, Chronological Regional Temperature and Precipitation Listings by Station
 
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 Emerald Bay Beach, station id OLB 10, in the San Joaquin HSA. Lat/Long: 33.55099/-117.80801.
Temporal Representation: Samples were collected weekly from January 1999 through December 2007; however, rainfall data is only available from March 2002 through December 2007.
Environmental Conditions: Comparisons were made for all data and data associated with storm events. A storm event was defined as 0.2 inches of rainfall within a 72 hour period.

Analyzing only storm water bacteria data is important because the majority of beach monitoring data covers the months of April through October. The data may not capture the full impacts of seasonal storm events and high bacteria levels due to storm water runoff because much of the wet season for Southern California occurs in November through March.
QAPP Information: Quality control for the bacteria analysis portion of this study was conducted in accordance with the County of Orange Quality Assessment/Quality Control document.
QAPP Information Reference(s): County of Orange. Quality Assurance/Quality Control Manual, February 2004 Bacteria specific
 
 
DECISION ID
17709
Region 9     
Pacific Ocean Shoreline, San Joaquin Hills HSA, at Emerald Bay Beach
 
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: In 2006, 'Pacific Ocean Shoreline, San Joaquin Hills HSA' was listed for Indicator Bacteria. For 2008, the 2006 San Joaquin Hills HSA segment has been split into smaller segments and each represents an area near the sampling location of the data being assessed. 'Pacific Ocean Shoreline, San Joaquin Hills HSA, at Emerald Bay Beach' is one of the sampling locations for Pacific Ocean Shoreline, San Joaquin Hills HSA, 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 3.3 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. Six of 452 samples exceeded the water quality objective Shellfish Harvesting 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 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.

In LOEs 30425 and 30443, 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 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. Six of 452 samples exceeded the shellfish harvesting water quality objective and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy.
5. Zero of 56 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.
4. 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 17709, Total Coliform
Region 9     
Pacific Ocean Shoreline, San Joaquin Hills HSA, at Emerald Bay Beach
 
LOE ID: 30425
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Shellfish Harvesting
 
Number of Samples: 49
Number of Exceedances: 3
 
Data and Information Type: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: Beach monitoring data was collected by the County of Orange from January 1999 through December 2007. A total of 452 single samples were collected. Between March 2002 and December 2007, 49 samples were associated with a storm event. From the 49 samples, three 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: Ocean Bacteriological Data Evaluation for City of Laguna Beach, 1999 through 2006, Final Report
  National Weather Service Forecast Office, San Diego, California, Chronological Regional Temperature and Precipitation Listings by Station
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: From the Ocean Plan, the median 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 (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 Emerald Bay Beach, station id OLB 10, in the San Joaquin HSA. Lat/Long: 33.55099/-117.80801.
Temporal Representation: Samples were collected weekly from January 1999 through December 2007; however, rainfall data is only available from March 2002 through December 2007.
Environmental Conditions: Comparisons were made for all data and data associated with storm events. A storm event was defined as 0.2 inches of rainfall within a 72 hour period.

Analyzing only storm water bacteria data is important because the majority of beach monitoring data covers the months of April through October. The data may not capture the full impacts of seasonal storm events and high bacteria levels due to storm water runoff because much of the wet season for Southern California occurs in November through March.
QAPP Information: Quality control for the bacteria analysis portion of this study was conducted in accordance with the County of Orange 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 17709, Total Coliform
Region 9     
Pacific Ocean Shoreline, San Joaquin Hills HSA, at Emerald Bay Beach
 
LOE ID: 30442
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 452
Number of Exceedances: 0
 
Data and Information Type: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: Beach monitoring data was collected by the County of Orange from January 1999 through December 2007. A total of 452 single samples were collected with none exceeding the single sample water quality objective.
Data Reference: Ocean Bacteriological Data Evaluation for City of Laguna Beach, 1999 through 2006, Final Report
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Single Sample Maximum: Total coliform density shall not exceed 10,000 per 100ml;

Geomean: Total coliform density shall not exceed 1,000 per 100ml (SWRCB, 2005).
Objective/Criterion Reference: Water Quality Control Plan Ocean Waters of California. California Ocean Plan 2005. Sacramento, CA: State Water Resources Control Board, California Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from Emerald Bay Beach, station id OLB 10, in the San Joaquin HSA. Lat/Long: 33.55099/-117.80801.
Temporal Representation: Samples were collected weekly from January 1999 through December 2007; however, rainfall data is only available from March 2002 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 Orange 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 17709, Total Coliform
Region 9     
Pacific Ocean Shoreline, San Joaquin Hills HSA, at Emerald Bay Beach
 
LOE ID: 30421
 
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, San Joaquin Hills HSA' was split into smaller segments and each represents an area near the sampling location of the data being assessed. This segment 'Pacific Ocean Shoreline, San Joaquin Hills HSA, at Emerald Bay Beach' is one of the sampling locations. This LOE is a copy of the 2006 listing placeholder LOE for Pacific Ocean Shoreline, San Joaquin Hills HSA 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 17709, Total Coliform
Region 9     
Pacific Ocean Shoreline, San Joaquin Hills HSA, at Emerald Bay Beach
 
LOE ID: 31107
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 56
Number of Exceedances: 0
 
Data and Information Type: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: Orange County collected Beach monitoring data within the time period from January 1999 through December 2006.
A total of 56 monthly geomeans were calculated for data collected during the time frame of April 1st to October 31st (AB411 data) within the aforementioned time period. Of the 56 geomeans zero exceeded the geomean water quality objective.
Data Reference: Ocean Bacteriological Data Evaluation for City of Laguna Beach, 1999 through 2006, Final Report
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The 30-day Geometric Mean for total coliform density shall not exceed 1000 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 Emerald Bay Beach, station id OLB 10, in the San Joaquin HSA. Lat/Long: 33.55099/-117.80801.
Temporal Representation: Samples were collected at least once a week within the time period from January 1999 through December 2006.
The data assessed is AB411 data which is data collected during the time frame of April 1st to October 31st (summer months) within the aforementioned time period.
Environmental Conditions:
QAPP Information: Quality control for the bacteria analysis portion of this study was conducted in accordance with the County of Orange 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 17709, Total Coliform
Region 9     
Pacific Ocean Shoreline, San Joaquin Hills HSA, at Emerald Bay Beach
 
LOE ID: 30440
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 108
Number of Exceedances: 0
 
Data and Information Type: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: Beach monitoring data was collected by the County of Orange from January 1999 through December 2007. A total of 452 single samples were collected and 108 monthly geomeans calculated. None of the 108 geomeans exceeded the geomean water quality objective.
Data Reference: Ocean Bacteriological Data Evaluation for City of Laguna Beach, 1999 through 2006, Final Report
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Single Sample Maximum: Total coliform density shall not exceed 10,000 per 100ml;

Geomean: Total coliform density shall not exceed 1,000 per 100ml (SWRCB, 2005).
Objective/Criterion Reference: Water Quality Control Plan Ocean Waters of California. California Ocean Plan 2005. Sacramento, CA: State Water Resources Control Board, California Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from Emerald Bay Beach, station id OLB 10, in the San Joaquin HSA. Lat/Long: 33.55099/-117.80801.
Temporal Representation: Samples were collected weekly from January 1999 through December 2007; however, rainfall data is only available from March 2002 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 Orange 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 17709, Total Coliform
Region 9     
Pacific Ocean Shoreline, San Joaquin Hills HSA, at Emerald Bay Beach
 
LOE ID: 30424
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Shellfish Harvesting
 
Number of Samples: 452
Number of Exceedances: 6
 
Data and Information Type: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: Beach monitoring data was collected by the County of Orange from January 1999 through December 2007. A total of 452 single samples were collected with six samples exceeding the single sample water quality objective.
Data Reference: Ocean Bacteriological Data Evaluation for City of Laguna Beach, 1999 through 2006, Final Report
 
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 (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 Emerald Bay Beach, station id OLB 10, in the San Joaquin HSA. Lat/Long: 33.55099/-117.80801.
Temporal Representation: Samples were collected weekly from January 1999 through December 2007; however, rainfall data is only available from March 2002 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 Orange 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 17709, Total Coliform
Region 9     
Pacific Ocean Shoreline, San Joaquin Hills HSA, at Emerald Bay Beach
 
LOE ID: 30439
 
Pollutant: Indicator Bacteria
LOE Subgroup: Health Advisories
Matrix: -N/A
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 1460
Number of Exceedances: 4
 
Data and Information Type: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: For the period from January 2004 to December 2007, there were and 4 beach postings days for this section of shoreline. Bacteriological samples are collected on a weekly basis at approximately 150 ocean and bay location in Orange County. When a bacteriological sample exceeds water quality standards, signs are posted indicating that waters have exceeded public health standards.

Data and information on the number of beach posting were summarized by the County of Orange in their Annual Ocean and Bay Water Quality Report, March 2007. The reporting period was from January 2004 -December 2007. Data used was the number of days the beach was posting when the ocean or bay failed to meet the bacteriological standards.
Data Reference: County of Orange. March 2007. Annual Ocean and Bay Water Quality Report, 2006
 
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:
 
Spatial Representation: Bacteriological monitoring samples was collected at Emerald Bay beach shoreline.
Temporal Representation: The beach posting covers the time frame of January 2004 -December 2007.
Environmental Conditions:
QAPP Information: Samples were collected in compliance with County of Orange's Quality Assessment/Quality Control document (County of Orange, 2004).
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 17709, Total Coliform
Region 9     
Pacific Ocean Shoreline, San Joaquin Hills HSA, at Emerald Bay Beach
 
LOE ID: 30443
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 49
Number of Exceedances: 0
 
Data and Information Type: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: Beach monitoring data was collected by the County of Orange from January 1999 through December 2007. A total of 452 single samples were collected. Between March 2002 and December 2007, 49 samples were correlated with a storm event. None of the 49 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: Ocean Bacteriological Data Evaluation for City of Laguna Beach, 1999 through 2006, Final Report
  National Weather Service Forecast Office, San Diego, California, Chronological Regional Temperature and Precipitation Listings by Station
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Single Sample Maximum: Total coliform density shall not exceed 10,000 per 100ml;

Geomean: Total coliform density shall not exceed 1,000 per 100ml (SWRCB, 2005).
Objective/Criterion Reference: Water Quality Control Plan Ocean Waters of California. California Ocean Plan 2005. Sacramento, CA: State Water Resources Control Board, California Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from Emerald Bay Beach, station id OLB 10, in the San Joaquin HSA. Lat/Long: 33.55099/-117.80801.
Temporal Representation: Samples were collected weekly from January 1999 through December 2007; however, rainfall data is only available from March 2002 through December 2007.
Environmental Conditions: Comparisons were made for all data and data associated with storm events. A storm event was defined as 0.2 inches of rainfall within a 72 hour period.

Analyzing only storm water bacteria data is important because the majority of beach monitoring data covers the months of April through October. The data may not capture the full impacts of seasonal storm events and high bacteria levels due to storm water runoff because much of the wet season for Southern California occurs in November through March.
QAPP Information: Quality control for the bacteria analysis portion of this study was conducted in accordance with the County of Orange Quality Assessment/Quality Control document.
QAPP Information Reference(s): County of Orange. Quality Assurance/Quality Control Manual, February 2004 Bacteria specific