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

Supporting Information

Regional Board 3 - Central Coast Region

Water Body Name:	CCC Creek (Santa Cruz County)
Water Body ID:	CAR3051003020200327058585
Water Body Type:	River & Stream


DECISION ID	129393	Region 3
CCC Creek (Santa Cruz County)

Pollutant:	Ammonia
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 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. Four lines of evidence (LOEs) are available in the administrative record to assess this pollutant. Sample and exceedance counts for the lines of evidence with the fraction identified as "dissolved" are grouped together with those having the fraction “total”, based on the analytical method used. The following is a summary of the sample and exceedances for each beneficial use: Based on LOEs summarizing total ammonia data (‘nitrogen, ammonia’ and ‘nitrogen as ammonia’) zero of the five samples exceed the EPA's Lifetime Health advisory level set to protect municipal and domestic supply uses. 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 sample size is insufficient to determine an applicable beneficial use support rating with the power and confidence of the Listing Policy. In accordance with Table 3.1 of the Listing Policy, a minimum of 16 samples is needed to determine if a beneficial use is fully supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported. 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 samples exceed the water quality objectives and this does 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:

Line of Evidence (LOE) for Decision ID 129393, Ammonia	Region 3
CCC Creek (Santa Cruz County)

LOE ID:

183927

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed City of Watsonville Pinto Lake Monitoring data for CCC Creek (Santa Cruz County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N.

Data Reference:

Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

EPA's Lifetime Health advisory level for total ammonia is 30.0 mg/L as stated on page 8 of the 2012 edition of the drinking water standards and health advisories. This Advisory Level is defined as 'the concentration of a chemical in drinking water that is not expected to cause any adverse noncarcinogenic effects for a lifetime of exposure.'

Guideline Reference:

2018 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site (PLCCCOutlet)

Temporal Representation:

The samples were collected between the dates of 2017-01-03 and 2017-01-03

Environmental Conditions:

QAPP Information:

City of Watsonville. 2015. Pinto Lake Restoration Project Quality Assurance Program Plan.

QAPP Information Reference(s):

Pinto Lake Restoration Project Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 129393, Ammonia	Region 3
CCC Creek (Santa Cruz County)

LOE ID:

184066

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed City of Watsonville Pinto Lake Monitoring data for CCC Creek (Santa Cruz County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Ammonia as N.

Data Reference:

Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

2018 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site (PLCCCOutlet)

Temporal Representation:

The samples were collected between the dates of 2016-12-08 and 2016-12-15

Environmental Conditions:

QAPP Information:

City of Watsonville. 2015. Pinto Lake Restoration Project Quality Assurance Program Plan.

QAPP Information Reference(s):

Pinto Lake Restoration Project Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 129393, Ammonia	Region 3
CCC Creek (Santa Cruz County)

LOE ID:

183910

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

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:

Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

2018 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site (PLCCC)

Temporal Representation:

The samples were collected between the dates of 2016-01-05 and 2016-01-05

Environmental Conditions:

QAPP Information:

City of Watsonville. 2015. Pinto Lake Restoration Project Quality Assurance Program Plan.

QAPP Information Reference(s):

Pinto Lake Restoration Project Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 129393, Ammonia	Region 3
CCC Creek (Santa Cruz County)

LOE ID:

183772

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

2018 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site (PLCCC)

Temporal Representation:

The samples were collected between the dates of 2016-01-19 and 2016-01-19

Environmental Conditions:

QAPP Information:

City of Watsonville. 2015. Pinto Lake Restoration Project Quality Assurance Program Plan.

QAPP Information Reference(s):

Pinto Lake Restoration Project Quality Assurance Program Plan


DECISION ID	125780	Region 3
CCC Creek (Santa Cruz County)

Pollutant:	Nitrate
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 CWA section 303(d) List under sections 3.1 and 3.11 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.11, additional lines of evidence are necessary to support a listing decision. Six lines of evidence are available in the administrative record to assess this pollutant. Zero of the five samples exceed the water quality objective for the Municipal and Domestic Supply beneficial use. This sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. Although five of the five samples exceed the evaluation guideline used to interpret the narrative water quality objective for biostimulatory substances (Central Coast Region Technical Report, 2010), there is no supporting data, such as dissolved oxygen or chlorophyll a measurements, to support the conclusion that nitrate contributes to or causes a bio stimulatory effect in this waterbody segment. Therefore, the weight of evidence approach cannot be applied in accordance with section 3.11 of the Listing Policy and the use rating is set to insufficient information. Based on the readily 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. 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 samples exceed the water quality objective for Municipal and Domestic supply and this does 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:

Line of Evidence (LOE) for Decision ID 125780, Nitrate	Region 3
CCC Creek (Santa Cruz County)

LOE ID:

172583

Pollutant:

Nitrogen, Nitrate

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:

Water Board staff assessed City of Watsonville Pinto Lake Monitoring data for CCC Creek (Santa Cruz County) to determine beneficial use support and results are as follows: 3 of 3 samples exceeded the water quality threshold for Nitrate as N.

Data Reference:

Water data for the 2020/2022 integrated report in Region 3.

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 (Water Quality Control Plan, Central Coast Basin).

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:

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:

The samples were collected at 1 monitoring site (PLCCCOutlet)

Temporal Representation:

The samples were collected between the dates of 2016-12-08 and 2017-01-03

Environmental Conditions:

QAPP Information:

City of Watsonville. 2015. Pinto Lake Restoration Project Quality Assurance Program Plan.

QAPP Information Reference(s):

Pinto Lake Restoration Project Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 125780, Nitrate	Region 3
CCC Creek (Santa Cruz County)

LOE ID:

173359

Pollutant:

Nitrogen, Nitrate

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:

Water Board staff assessed City of Watsonville Pinto Lake Monitoring data for CCC Creek (Santa Cruz County) to determine beneficial use support and results are as follows: 2 of 2 samples exceeded the water quality threshold for Nitrate as N.

Data Reference:

Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (PLCCC)

Temporal Representation:

The samples were collected between the dates of 2016-01-05 and 2016-01-19

Environmental Conditions:

QAPP Information:

City of Watsonville. 2015. Pinto Lake Restoration Project Quality Assurance Program Plan.

QAPP Information Reference(s):

Pinto Lake Restoration Project Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 125780, Nitrate	Region 3
CCC Creek (Santa Cruz County)

LOE ID:

172558

Pollutant:

Nitrogen, Nitrate

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:

Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (PLCCC)

Temporal Representation:

The samples were collected between the dates of 2016-01-05 and 2016-01-19

Environmental Conditions:

QAPP Information:

City of Watsonville. 2015. Pinto Lake Restoration Project Quality Assurance Program Plan.

QAPP Information Reference(s):

Pinto Lake Restoration Project Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 125780, Nitrate	Region 3
CCC Creek (Santa Cruz County)

LOE ID:

173561

Pollutant:

Nitrogen, Nitrate

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:

Data Reference:

Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (PLCCCOutlet)

Temporal Representation:

The samples were collected between the dates of 2016-12-08 and 2017-01-03

Environmental Conditions:

QAPP Information:

City of Watsonville. 2015. Pinto Lake Restoration Project Quality Assurance Program Plan.

QAPP Information Reference(s):

Pinto Lake Restoration Project Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 125780, Nitrate	Region 3
CCC Creek (Santa Cruz County)

LOE ID:

172017

Pollutant:

Nitrogen, Nitrate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed City of Watsonville Pinto Lake Monitoring data for CCC Creek (Santa Cruz County) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Nitrate as N.

Data Reference:

Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

All inland surface waters, enclosed bays, and estuaries shall not contain concentrations of inorganic chemicals in excess of the maximum contaminant levels for primary drinking water standards specified in California Code of Regulations, Title 22, Division 4, Chapter 15, Sections 64431 and 64433.2.

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

The California Maximum Contaminant Level for nitrate (as N) 10.0 mg/L (California Code of Regulations, Title 22).

Guideline Reference:

California MCLs - Title 17 and Title 22 documents for 2019 - California Regulations Related to Drinking Water

Spatial Representation:

The samples were collected at 1 monitoring site (PLCCCOutlet)

Temporal Representation:

The samples were collected between the dates of 2016-12-08 and 2017-01-03

Environmental Conditions:

QAPP Information:

City of Watsonville. 2015. Pinto Lake Restoration Project Quality Assurance Program Plan.

QAPP Information Reference(s):

Pinto Lake Restoration Project Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 125780, Nitrate	Region 3
CCC Creek (Santa Cruz County)

LOE ID:

172448

Pollutant:

Nitrogen, Nitrate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

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:

Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

The California Maximum Contaminant Level for nitrate (as N) 10.0 mg/L (California Code of Regulations, Title 22).

Guideline Reference:

California MCLs - Title 17 and Title 22 documents for 2019 - California Regulations Related to Drinking Water

Spatial Representation:

The samples were collected at 1 monitoring site (PLCCC)

Temporal Representation:

The samples were collected between the dates of 2016-01-05 and 2016-01-19

Environmental Conditions:

QAPP Information:

City of Watsonville. 2015. Pinto Lake Restoration Project Quality Assurance Program Plan.

QAPP Information Reference(s):

Pinto Lake Restoration Project Quality Assurance Program Plan