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

Supporting Information

Regional Board 8 - Santa Ana Region

Water Body Name:	Warm Creek
Water Body ID:	CAR8015200020080921202752
Water Body Type:	River & Stream


DECISION ID	97048	Region 8
Warm Creek

Pollutant:	Indicator Bacteria
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Sources:	A Source Unknown
Expected TMDL Completion Date:	2029
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Four (4) lines of evidence are available in the administrative record to assess this pollutant. Forty-two (42) of the 70 samples exceed the E. coli Geomean Objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Forty-two (42) of the 70 samples exceed the E. coli Geomean, and this does exceed the frequency listed in table 3.2 4. The line of evidence based on the single sample maximum was not included in the Final Use Rating as the Region 8 Basin Plan states that where a representative geometric mean can be calculated, single sample maximum values shall not be used for assessment (page 4-17, footnote 3). 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 be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 97048, Indicator Bacteria	Region 8
Warm Creek

LOE ID:

82601

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

102

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Forty-nine of the 102 samples exceeded the E. coli evaluation guideline.

Data Reference:

Data for Various Pollutants in Region 8, 2008-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses. Santa Ana Region basin Plan.

Objective/Criterion Reference:

Water Quality Control Plan, Santa Ana River Basin

Evaluation Guideline:

The single sample E. coli concentration shall not exceed more than 235/100ml. USEPA Ambient Water Quality Criteria for Bacteria -1986.

Guideline Reference:

Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002

Spatial Representation:

The samples were collected from Warm Creek WC2 and WC4. NOTE: request to move WC4 to Lytle Creek but need mapping confirmation.

Temporal Representation:

The samples were collected once a week from July 2008 to November 2009.

Environmental Conditions:

QAPP Information:

Data was collected under the Qality Assurance Project Plan for the Upper Santa Ana River Watershed Water Quality Assessment Project.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 97048, Indicator Bacteria	Region 8
Warm Creek

LOE ID:

82603

Pollutant:

Total Coliform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

102

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Sixty-eight of the 102 samples exceeded the total coliform evaluation guideline.

Data Reference:

Data for Various Pollutants in Region 8, 2008-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses. Santa Ana Region basin Plan.

Objective/Criterion Reference:

Water Quality Control Plan, Santa Ana River Basin

Evaluation Guideline:

The single sample total coliform concentration shall not exceed more than 10,000/100ml. Guidance for Fresh Water Beaches (CDPH 2011).

Guideline Reference:

Draft Guidance for Fresh Water Beaches. Last Update: May 8, 2006. Initial Draft: November 1997. California Department of Public Health.

Spatial Representation:

The samples were collected from Warm Creek.

Temporal Representation:

The samples were collected once a week from July 2008 to November 2009.

Environmental Conditions:

QAPP Information:

Data was collected under the Qality Assurance Project Plan for the Upper Santa Ana River Watershed Water Quality Assessment Project.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 97048, Indicator Bacteria	Region 8
Warm Creek

LOE ID:

82604

Pollutant:

Total Coliform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Sixty-nine of the 70 samples exceeded the total coliform evaluation guideline for geometric mean.

Data Reference:

Data for Various Pollutants in Region 8, 2008-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses. Santa Ana Region basin Plan.

Objective/Criterion Reference:

Water Quality Control Plan, Santa Ana River Basin

Evaluation Guideline:

Geomean: The total coliform concentration for geometric mean shall not exceed more than 1000/100ml. Guidance for Fresh Water Beaches (CDPH 2011).

Guideline Reference:

Draft Guidance for Fresh Water Beaches. Last Update: May 8, 2006. Initial Draft: November 1997. California Department of Public Health.

Spatial Representation:

The samples were collected from East Warm Creek WC2 and WC4. NOTE: request to move station WC4 to Lytle Creek.

Temporal Representation:

The samples were collected once a week from July 2008 to November 2009.

Environmental Conditions:

QAPP Information:

Data was collected under the Qality Assurance Project Plan for the Upper Santa Ana River Watershed Water Quality Assessment Project.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 97048, Indicator Bacteria	Region 8
Warm Creek

LOE ID:

82602

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Forty-two of the 70 samples exceeded the E. coli evaluation guideline for geometric mean.

Data Reference:

Data for Various Pollutants in Region 8, 2008-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses. Santa Ana Region basin Plan.

Objective/Criterion Reference:

Water Quality Control Plan, Santa Ana River Basin

Evaluation Guideline:

Geomean: The E. coli concentration for geometric mean shall not exceed more than 126/100ml. USEPA Ambient Water Quality Criteria for Bacteria -1986.

Guideline Reference:

Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002

Spatial Representation:

The samples were collected from Warm Creek WC2 and WC4. NOTE: request to move WC4 to Lytle Creek. Will address on cycle, need better map.

Temporal Representation:

The samples were collected once a week from July 2008 to November 2009.

Environmental Conditions:

QAPP Information:

Data was collected under the Qality Assurance Project Plan for the Upper Santa Ana River Watershed Water Quality Assessment Project.

QAPP Information Reference(s):