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

Supporting Information

Regional Board 3 - Central Coast Region

Water Body Name:	Chumash Creek
Water Body ID:	CAR3102201120021001213514
Water Body Type:	River & Stream


DECISION ID	131033	Region 3
Chumash Creek

Pollutant:	Fecal Coliform
Final Listing Decision:	Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not Delist from 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Reason for Delisting:	Applicable WQS attained; due to change in WQS
TMDL Name:	Morro Bay Pathogens
TMDL Project Code:	22
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for removal from the CWA section 303(d) List under section 4 of the Listing Policy due to a change in water quality standards. The State Water Boards Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California (the ISWEBE Plan) contains two bacteria water quality objectives applicable to the REC-1 beneficial use which were adopted on August 7, 2018: where the salinity level of a waterbody is equal to or less than 1 part per thousand 95 percent or more of the time, the E. coli bacteria objective applies; and where the salinity level of a waterbody is greater than 1 part per thousand 95 percent or more of the time, the Enterococci bacteria objective applies. These objectives supersede the fecal coliform water quality objective for water contact recreation. Consequently, the fecal coliform objective for water contact recreation is no longer applicable to this waterbody and those LOEs have been removed from this decision. Therefore, this waterbody is being removed from the CWA section 303(d) List under section 4 of the Listing Policy due to a change in water quality standards.

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 CWA section 303(d) List under section 4 of the Listing Policy due to a change in water quality standards. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

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 131033, Fecal Coliform	Region 3
Chumash Creek

LOE ID:

228056

Pollutant:

Fecal Coliform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Non-Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Placeholder LOE so that we can create 2020 decision to delist now that the REC1 LOEs are obsolete.

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Placeholder LOE so that we can create 2020 decision to delist now that the REC1 LOEs are obsolete.

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

Placeholder LOE so that we can create 2020 decision to delist now that the REC1 LOEs are obsolete.

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Placeholder LOE so that we can create 2020 decision to delist now that the REC1 LOEs are obsolete.

Temporal Representation:

Placeholder LOE so that we can create 2020 decision to delist now that the REC1 LOEs are obsolete.

Environmental Conditions:

Placeholder LOE so that we can create 2020 decision to delist now that the REC1 LOEs are obsolete.

QAPP Information:

Placeholder LOE so that we can create 2020 decision to delist now that the REC1 LOEs are obsolete.

QAPP Information Reference(s):

Placeholder reference 2006 303(d)


DECISION ID	86082	Region 3
Chumash Creek

Pollutant:	Nitrate
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
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 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. Zero of the seven samples exceed the water quality objective for Municipal and Domestic Supply and zero of the seven samples exceed the evaluation guideline for Cold and Warm Freshwater Habitats. This sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported using table 3.1. Therefore, the use support rating is set to 'insufficient 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 CWA 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. Zero of the seven samples exceed the water quality objective for Municipal and Domestic Supply and zero of the seven samples exceed the evaluation guideline for Cold and Warm Freshwater Habitats. These do not exceed the allowable frequency listed in Table 3.1 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. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

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 86082, Nitrate	Region 3
Chumash Creek

LOE ID:

47741

Pollutant:

Nitrate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Region 3 - Central Coast Region staff assessed R3 public submissions data for Chumash Creek to determine beneficial use support and results are as follows: 0 of 7 samples exceed the criterion for Nitrate as N.

Data Reference:

Data from Morro Bay National Estuary Program's Volunteer Monitoring Program, May 2002-Apr. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Basin Plan).

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.

Guideline Reference:

Technical Approach to Develop Nutrient Numeric Endpoints for California. U.S. EPA Region IX. State Water Resources Control Board. 68-C-02-108-To-111

Guideline Reference:

Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.

Spatial Representation:

Data for this line of evidence for Chumash Creek was collected at 1 monitoring site [ 310CHU - Chumash Creek, named tributary to Pennington.]

Temporal Representation:

Data was collected over the time period 2/12/2003 3:25:00 PM-4/1/2005 2:15:00 PM.

Environmental Conditions:

Nitrate data was collected using a screening level test kit. Quality control is consistent with the QAPP.

QAPP Information:

All data was collected in compliance with an EPA approved QAPP

QAPP Information Reference(s):

Quality Assurance Project Plan for Morro Bay National Estuary Program¿s Volunteer Monitoring Program. Jan. 12, 2010, Version 5, Draft 2

Line of Evidence (LOE) for Decision ID 86082, Nitrate	Region 3
Chumash Creek

LOE ID:

47742

Pollutant:

Nitrate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data from Morro Bay National Estuary Program's Volunteer Monitoring Program, May 2002-Apr. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for nitrate (NO3 as N) incorporated by reference in the Basin Plan is 10.0 mg/L (Basin Plan).

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chumash Creek was collected at 1 monitoring site [ 310CHU - Chumash Creek, named tributary to Pennington.]

Temporal Representation:

Data was collected over the time period 2/12/2003 3:25:00 PM-4/1/2005 2:15:00 PM.

Environmental Conditions:

Nitrate data was collected using a screening level test kit. Quality control is consistent with the QAPP.

QAPP Information:

All data was collected in compliance with an EPA approved QAPP

QAPP Information Reference(s):

Quality Assurance Project Plan for Morro Bay National Estuary Program¿s Volunteer Monitoring Program. Jan. 12, 2010, Version 5, Draft 2

Line of Evidence (LOE) for Decision ID 86082, Nitrate	Region 3
Chumash Creek

LOE ID:

47743

Pollutant:

Nitrate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data from Morro Bay National Estuary Program's Volunteer Monitoring Program, May 2002-Apr. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Basin Plan).

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Technical Approach to Develop Nutrient Numeric Endpoints for California. U.S. EPA Region IX. State Water Resources Control Board. 68-C-02-108-To-111

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chumash Creek was collected at 1 monitoring site [ 310CHU - Chumash Creek, named tributary to Pennington.]

Temporal Representation:

Data was collected over the time period 2/12/2003 3:25:00 PM-4/1/2005 2:15:00 PM.

Environmental Conditions:

Nitrate data was collected using a screening level test kit. Quality control is consistent with the QAPP.

QAPP Information:

All data was collected in compliance with an EPA approved QAPP

QAPP Information Reference(s):

Quality Assurance Project Plan for Morro Bay National Estuary Program¿s Volunteer Monitoring Program. Jan. 12, 2010, Version 5, Draft 2


DECISION ID	80850	Region 3
Chumash Creek

Pollutant:	Temperature, water
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
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. One line of evidence is available in the administrative record to assess this pollutant. Zero of the 7 samples exceed the evaluation guideline (Moyle, 1976) used to interpret the water quality objective for water temperature. This sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 26 samples is needed to determine if a beneficial use is supported and a minimum of five exceedances is needed to determine if beneficial uses are not supported using table 3.2. Therefore, the use support rating is set to 'insufficient 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 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. Zero of the 7 samples exceed the evaluation guideline and this does not exceed the allowable frequency listed in Table 3.2 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. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

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 80850, Temperature, water	Region 3
Chumash Creek

LOE ID:

47924

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data from Morro Bay National Estuary Program's Volunteer Monitoring Program, May 2002-Apr. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses (Basin Plan).

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

The optimum range for growth and completion of most life stages of rainbow trout is 13-21 degrees Celsius (Moyle 1976).

Guideline Reference:

The Effects of Turbidity on Prey Selection by Piscivorous Largemouth Bass

Spatial Representation:

Data for this line of evidence for Chumash Creek was collected at 1 monitoring site [ 310CHU - Chumash Creek, named tributary to Pennington.]

Temporal Representation:

Data was collected over the time period 2/12/2003 3:25:00 PM-4/1/2005 2:15:00 PM.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

All data was collected in compliance with an EPA approved QAPP

QAPP Information Reference(s):

Quality Assurance Project Plan for Morro Bay National Estuary Program¿s Volunteer Monitoring Program. Jan. 12, 2010, Version 5, Draft 2


DECISION ID	80851	Region 3
Chumash Creek

Pollutant:	Turbidity
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
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. Two lines of evidence are available in the administrative record to assess this pollutant. Zero of the 7 samples exceed the cold freshwater habitat evaluation guideline (Sigler et al. 1984) and the warm freshwater habitat evaluation guideline (Shoup, D.E. and Wahl D.H., 2009), both used to interpret the water quality objective for turbidity. This sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 26 samples is needed to determine if a beneficial use is supported and a minimum of five exceedances is needed to determine if beneficial uses are not supported using table 3.2. Therefore, the use support rating is set to 'insufficient 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 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. Zero of the 7 samples exceed the evaluation guidelines and this does not exceed the allowable frequency listed in Table 3.2 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. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

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 80851, Turbidity	Region 3
Chumash Creek

LOE ID:

47916

Pollutant:

Turbidity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data from Morro Bay National Estuary Program's Volunteer Monitoring Program, May 2002-Apr. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses. (Basin Plan)

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Turbidities of 25 NTU or greater can cause a reduction in juvenile salmonid growth due to interference with their ability to find food (Sigler et al. 1984).

Guideline Reference:

Effects of chronic turbidity on density and growth of steelheads and coho salmon. Transactions of the American Fisheries Society 113:142-150

Spatial Representation:

Data for this line of evidence for Chumash Creek was collected at 1 monitoring site [ 310CHU - Chumash Creek, named tributary to Pennington.]

Temporal Representation:

Data was collected over the time period 2/12/2003 3:25:00 PM-4/1/2005 2:15:00 PM.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

All data was collected in compliance with an EPA approved QAPP

QAPP Information Reference(s):

Quality Assurance Project Plan for Morro Bay National Estuary Program¿s Volunteer Monitoring Program. Jan. 12, 2010, Version 5, Draft 2

Line of Evidence (LOE) for Decision ID 80851, Turbidity	Region 3
Chumash Creek

LOE ID:

47923

Pollutant:

Turbidity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data from Morro Bay National Estuary Program's Volunteer Monitoring Program, May 2002-Apr. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses (Basin Plan).

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Turbidities of 40 NTU or greater can cause a reduction in piscivorous fish (largemouth bass) growth due to interference with their ability to find food (Shoup, D.E. and Wahl D.H., 2009).

Guideline Reference:

Effects of chronic turbidity on density and growth of steelheads and coho salmon. Transactions of the American Fisheries Society 113:142-150

Spatial Representation:

Data for this line of evidence for Chumash Creek was collected at 1 monitoring site [ 310CHU - Chumash Creek, named tributary to Pennington.]

Temporal Representation:

Data was collected over the time period 2/12/2003 3:25:00 PM-4/1/2005 2:15:00 PM.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

All data was collected in compliance with an EPA approved QAPP

QAPP Information Reference(s):

Quality Assurance Project Plan for Morro Bay National Estuary Program¿s Volunteer Monitoring Program. Jan. 12, 2010, Version 5, Draft 2


DECISION ID	80852	Region 3
Chumash Creek

Pollutant:	pH
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
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. Five lines of evidence are available in the administrative record to assess this pollutant. Five beneficial uses are assessed. Zero of the 7 samples exceeded the water quality objectives for Drinking Water and Recreation and 1 of the 7 samples exceed the water quality objective for Cold Freshwater Habitats. This sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 26 samples is needed to determine if a beneficial use is supported and a minimum of five exceedances is needed to determine if beneficial uses are not supported using table 3.2. Therefore, the use support rating is set to 'insufficient 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 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. Zero of the 7 samples exceeded the water quality objectives for Drinking Water and Recreation and 1 of the 7 samples exceed the water quality objective for Cold Freshwater Habitats. None of these exceed the allowable frequency listed in Table 3.2 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. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

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 80852, pH	Region 3
Chumash Creek

LOE ID:

47911

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Region 3 - Central Coast Region staff assessed R3 public submissions data for Chumash Creek to determine beneficial use support and results are as follows: 1 of 7 samples exceed the criterion for pH.

Data Reference:

Data from Morro Bay National Estuary Program's Volunteer Monitoring Program, May 2002-Apr. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The pH value shall not be depressed below 7.0 or raised above 8.5 (Basin Plan).

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chumash Creek was collected at 1 monitoring site [ 310CHU - Chumash Creek, named tributary to Pennington.]

Temporal Representation:

Data was collected over the time period 2/12/2003 3:25:00 PM-4/1/2005 2:15:00 PM.

Environmental Conditions:

pH was measured using test strips. In recent communication with the program QA officer concern has been raised about underestimation of the result with test strips.

QAPP Information:

All data was collected in compliance with an EPA approved QAPP

QAPP Information Reference(s):

Quality Assurance Project Plan for Morro Bay National Estuary Program¿s Volunteer Monitoring Program. Jan. 12, 2010, Version 5, Draft 2

Line of Evidence (LOE) for Decision ID 80852, pH	Region 3
Chumash Creek

LOE ID:

47912

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Region 3 - Central Coast Region staff assessed R3 public submissions data for Chumash Creek to determine beneficial use support and results are as follows: 0 of 7 samples exceed the criterion for pH.

Data Reference:

Data from Morro Bay National Estuary Program's Volunteer Monitoring Program, May 2002-Apr. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The pH value shall not be depressed below 6.5 or raised above 8.3 (Basin Plan).

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chumash Creek was collected at 1 monitoring site [ 310CHU - Chumash Creek, named tributary to Pennington.]

Temporal Representation:

Data was collected over the time period 2/12/2003 3:25:00 PM-4/1/2005 2:15:00 PM.

Environmental Conditions:

pH was measured using test strips. In recent communication with the program QA officer concern has been raised about underestimation of the result with test strips.

QAPP Information:

All data was collected in compliance with an EPA approved QAPP

QAPP Information Reference(s):

Quality Assurance Project Plan for Morro Bay National Estuary Program¿s Volunteer Monitoring Program. Jan. 12, 2010, Version 5, Draft 2

Line of Evidence (LOE) for Decision ID 80852, pH	Region 3
Chumash Creek

LOE ID:

47914

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Non-Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Region 3 - Central Coast Region staff assessed R3 public submissions data for Chumash Creek to determine beneficial use support and results are as follows: 0 of 7 samples exceed the criterion for pH.

Data Reference:

Data from Morro Bay National Estuary Program's Volunteer Monitoring Program, May 2002-Apr. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The pH value shall neither be depressed below 6.5 nor raised above 8.3 (Basin Plan).

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chumash Creek was collected at 1 monitoring site [ 310CHU - Chumash Creek, named tributary to Pennington.]

Temporal Representation:

Data was collected over the time period 2/12/2003 3:25:00 PM-4/1/2005 2:15:00 PM.

Environmental Conditions:

pH was measured using test strips. In recent communication with the program QA officer concern has been raised about underestimation of the result with test strips.

QAPP Information:

All data was collected in compliance with an EPA approved QAPP

QAPP Information Reference(s):

Quality Assurance Project Plan for Morro Bay National Estuary Program¿s Volunteer Monitoring Program. Jan. 12, 2010, Version 5, Draft 2

Line of Evidence (LOE) for Decision ID 80852, pH	Region 3
Chumash Creek

LOE ID:

47915

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Region 3 - Central Coast Region staff assessed R3 public submissions data for Chumash Creek to determine beneficial use support and results are as follows: 1 of 7 samples exceed the criterion for pH.

Data Reference:

Data from Morro Bay National Estuary Program's Volunteer Monitoring Program, May 2002-Apr. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The pH value shall not be depressed below 7.0 or raised above 8.5 (Basin Plan).

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chumash Creek was collected at 1 monitoring site [ 310CHU - Chumash Creek, named tributary to Pennington.]

Temporal Representation:

Data was collected over the time period 2/12/2003 3:25:00 PM-4/1/2005 2:15:00 PM.

Environmental Conditions:

pH was measured using test strips. In recent communication with the program QA officer concern has been raised about underestimation of the result with test strips.

QAPP Information:

All data was collected in compliance with an EPA approved QAPP

QAPP Information Reference(s):

Quality Assurance Project Plan for Morro Bay National Estuary Program¿s Volunteer Monitoring Program. Jan. 12, 2010, Version 5, Draft 2

Line of Evidence (LOE) for Decision ID 80852, pH	Region 3
Chumash Creek

LOE ID:

47913

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Region 3 - Central Coast Region staff assessed R3 public submissions data for Chumash Creek to determine beneficial use support and results are as follows: 0 of 7 samples exceed the criterion for pH.

Data Reference:

Data from Morro Bay National Estuary Program's Volunteer Monitoring Program, May 2002-Apr. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The pH value shall neither be depressed below 6.5 nor raised above 8.3 (Basin Plan).

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chumash Creek was collected at 1 monitoring site [ 310CHU - Chumash Creek, named tributary to Pennington.]

Temporal Representation:

Data was collected over the time period 2/12/2003 3:25:00 PM-4/1/2005 2:15:00 PM.

Environmental Conditions:

pH was measured using test strips. In recent communication with the program QA officer concern has been raised about underestimation of the result with test strips.

QAPP Information:

All data was collected in compliance with an EPA approved QAPP

QAPP Information Reference(s):

Quality Assurance Project Plan for Morro Bay National Estuary Program¿s Volunteer Monitoring Program. Jan. 12, 2010, Version 5, Draft 2


DECISION ID	80807	Region 3
Chumash Creek

Pollutant:	Escherichia coli (E. coli)
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:	2027
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.2 and 3.3 of the Listing Policy. Under these sections a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Thirteen of the 37 samples exceed the USEPA Ambient Water Quality Criteria for Bacteria (1986). Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the 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. Thirteen of the 37 samples exceed the USEPA Ambient Water Quality Criteria for Bacteria and this exceeds the allowable frequency listed in Table 3.2 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 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 80807, Escherichia coli (E. coli)	Region 3
Chumash Creek

LOE ID:

48017

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:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Region 3 - Central Coast Region staff assessed R3 public submissions data for Chumash Creek to determine beneficial use support and results are as follows: 13 of 37 samples exceed the criterion for Escherichia coli.

Data Reference:

Data from Morro Bay National Estuary Program's Volunteer Monitoring Program, May 2002-Apr. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

USEPA Ambient Water Quality Criteria for Bacteria -1986.

Objective/Criterion Reference:

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

Evaluation Guideline:

Single sample maximum allowable density for E. coli in freshwater is 235 MPN/100mL (as stated in Table 4, page 15 of the USEPA Ambient Water Quality Criteria for Bacteria -1986).

Guideline Reference:

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

Spatial Representation:

Data for this line of evidence for Chumash Creek was collected at 1 monitoring site [ 310CHU - Chumash Creek, named tributary to Pennington.]

Temporal Representation:

Data was collected over the time period 2/4/2003 2:45:00 PM-6/7/2006 12:00:00 PM.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

All data was collected in compliance with an EPA approved QAPP

QAPP Information Reference(s):

Quality Assurance Project Plan for Morro Bay National Estuary Program¿s Volunteer Monitoring Program. Jan. 12, 2010, Version 5, Draft 2


DECISION ID	80806	Region 3
Chumash Creek

Pollutant:	Oxygen, Dissolved
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:	2027
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. Five lines of evidence are available in the administrative record to assess this pollutant. Forty-two of the 252 samples exceed the water quality objective for cold freshwater habitat. The most recent data is also evaluated using the warm freshwater habitat objective and 2 of 7 samples exceed the evaluation guideline. The Basin Plan general water quality objective for oxygen saturation states that the median value shall not fall below 85% saturation. However, the oxygen saturation objective is only applied ¿for waters not mentioned by a specific beneficial use¿¿ and this water body is designated for both Cold and Warm Freshwater Habitats. Therefore, the saturation data is used only as supporting information and the use support rating for this pollutant is set at insufficient information. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the 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 of the 252 samples exceed the water quality objective for cold freshwater habitat and this exceeds the allowable frequency listed in Table 3.2 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 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 80806, Oxygen, Dissolved	Region 3
Chumash Creek

LOE ID:

47745

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Region 3 - Central Coast Region staff assessed R3 public submissions data for Chumash Creek to determine beneficial use support and results are as follows: 2 of 7 samples exceed the criterion for Oxygen, Dissolved.

Data Reference:

Data from Morro Bay National Estuary Program's Volunteer Monitoring Program, May 2002-Apr. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved oxygen concentration shall not be reduced below 5.0 mg/l at any time (Basin Plan).

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chumash Creek was collected at 1 monitoring site [ 310CHU - Chumash Creek, named tributary to Pennington.]

Temporal Representation:

Data was collected over the time period 2/12/2003 3:25:00 PM-4/1/2005 2:15:00 PM.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

All data was collected in compliance with an EPA approved QAPP

QAPP Information Reference(s):

Quality Assurance Project Plan for Morro Bay National Estuary Program¿s Volunteer Monitoring Program. Jan. 12, 2010, Version 5, Draft 2

Line of Evidence (LOE) for Decision ID 80806, Oxygen, Dissolved	Region 3
Chumash Creek

LOE ID:

1898

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Adverse Biological Responses

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

245

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Chumash Creek was placed on the 2002 303(d) list as impaired from dissolved oxygen because levels fell below the COLD freshwater habitat water quality objective of 7 mg/l. Forty samples of a total of 245 samples taken between 1993 and 2003 fall below this value (CCRWQCB, 2004k).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

COLD freshwater habitat water quality objective for D.O. = 7 mg/l (minimum).

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Measurements were taken at 310CHU on Chumash Creek, Calwater watershed no. 31022012.

Temporal Representation:

Two hundred forty five samples were collected over a ten year period of 6/8/1993-7/16/2003. Samples were collected on a monthly or bi-monthly basis.

Environmental Conditions:

QAPP Information:

Water column data collected by RWQCB staff in 1993-2001 were taken according to the National Monitoring Program Quality Assurance Program Plan. Samples taken in 2003 by the Morro Bay Volunteer Monitoring Program were taken according to protocols for dissolved oxygen sampling in the Morro Bay National Estuary Program's Quality Assurance Program Plan.

The Morro Bay Volunteer Monitoring Program staff have routine correspondence with volunteers regarding data review, meter operation, and safety. Volunteer monitors collect dissolved oxygen data according to the Morro Bay National Estuary Program's Quality Assurance Program Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 80806, Oxygen, Dissolved	Region 3
Chumash Creek

LOE ID:

47744

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data from Morro Bay National Estuary Program's Volunteer Monitoring Program, May 2002-Apr. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Basin Plan).

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chumash Creek was collected at 1 monitoring site [ 310CHU - Chumash Creek, named tributary to Pennington.]

Temporal Representation:

Data was collected over the time period 2/12/2003 3:25:00 PM-4/1/2005 2:15:00 PM.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

All data was collected in compliance with an EPA approved QAPP

QAPP Information Reference(s):

Quality Assurance Project Plan for Morro Bay National Estuary Program¿s Volunteer Monitoring Program. Jan. 12, 2010, Version 5, Draft 2