Draft California 2024 Integrated Report (303(d) List/305(b) Report)

Supporting Information

Regional Board 2 - San Francisco Bay Region

Water Body Name:	Tunitas Creek (San Mateo)
Water Body ID:	CAR2022300020210325063165
Water Body Type:	River & Stream


DECISION ID	143896	Region 2
Tunitas Creek (San Mateo)

Pollutant:	Alkalinity as CaCO3
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:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.

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 the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 143896, Alkalinity as CaCO3	Region 2
Tunitas Creek (San Mateo)

LOE ID:

277331

Pollutant:

Alkalinity as CaCO3

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 SWAMP RWB2 Monitoring data for Tunitas Creek (San Mateo) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Alkalinity as CaCO3.

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The USEPA recommended alkalinity criterion continuous concentration (CCC) for the protection of aquatic life in freshwater is a minimum value of 20,000 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN600 (Tunitas Creek - 1.0mi upstream of confluence with East Fork; 202R00376).

Temporal Representation:

The samples were collected between the dates of 2014-05-12 and 2014-05-12

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 143896, Alkalinity as CaCO3	Region 2
Tunitas Creek (San Mateo)

LOE ID:

277317

Pollutant:

Alkalinity as CaCO3

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The USEPA recommended alkalinity criterion continuous concentration (CCC) for the protection of aquatic life in freshwater is a minimum value of 20,000 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN600 (Tunitas Creek - 1.0mi upstream of confluence with East Fork; 202R00376).

Temporal Representation:

The samples were collected between the dates of 2014-05-12 and 2014-05-12

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 143896, Alkalinity as CaCO3	Region 2
Tunitas Creek (San Mateo)

LOE ID:

277233

Pollutant:

Alkalinity as CaCO3

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The USEPA recommended alkalinity criterion continuous concentration (CCC) for the protection of aquatic life in freshwater is a minimum value of 20,000 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN600 (Tunitas Creek - 1.0mi upstream of confluence with East Fork; 202R00376).

Temporal Representation:

The samples were collected between the dates of 2014-05-12 and 2014-05-12

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 143896, Alkalinity as CaCO3	Region 2
Tunitas Creek (San Mateo)

LOE ID:

276602

Pollutant:

Alkalinity as CaCO3

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:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The USEPA recommended alkalinity criterion continuous concentration (CCC) for the protection of aquatic life in freshwater is a minimum value of 20,000 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN600 (Tunitas Creek - 1.0mi upstream of confluence with East Fork; 202R00376).

Temporal Representation:

The samples were collected between the dates of 2014-05-12 and 2014-05-12

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.


DECISION ID	151034	Region 2
Tunitas Creek (San Mateo)

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:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

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 the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 151034, Ammonia	Region 2
Tunitas Creek (San Mateo)

LOE ID:

278424

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 BASMAA RMC Monitoring in WY2016 data for Tunitas Creek (San Mateo) 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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The USEPA Health Advisory for lifetime exposure to ammonia as a drinking water level is a concentration of 30 mg/L. 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 up to ten days of exposure.

Guideline Reference:

2018 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site: 202R00488 (Tunitas Creek Road and Lobitos Cut-off Rd).

Temporal Representation:

The samples were collected between the dates of 2016-05-10 and 2016-05-10

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 151034, Ammonia	Region 2
Tunitas Creek (San Mateo)

LOE ID:

278634

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.

Objective/Criterion Reference:

Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202R00488 (Tunitas Creek Road and Lobitos Cut-off Rd).

Temporal Representation:

The samples were collected between the dates of 2016-05-10 and 2016-05-10

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 151034, Ammonia	Region 2
Tunitas Creek (San Mateo)

LOE ID:

279029

Pollutant:

Ammonia (Unionized)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.20 Un-Ionized Ammonia: The discharge of wastes shall not cause receiving waters to contain concentrations of un-ionized ammonia in excess 0.025 mg/l (as N), expressed as an annual median.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN600 (Tunitas Creek - 1.0mi upstream of confluence with East Fork; 202R00376).

Temporal Representation:

The samples were collected between the dates of 2014-05-12 and 2014-05-12

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 151034, Ammonia	Region 2
Tunitas Creek (San Mateo)

LOE ID:

278887

Pollutant:

Ammonia (Unionized)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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 BASMAA RMC Monitoring in WY2019 data for Tunitas Creek (San Mateo) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N, Unionized.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN030 (Tunitas Creek at Tunitas Creek Rd & Lobitos Creek Cutoff).

Temporal Representation:

The samples were collected between the dates of 2019-07-31 and 2019-07-31

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 151034, Ammonia	Region 2
Tunitas Creek (San Mateo)

LOE ID:

280156

Pollutant:

Ammonia (Unionized)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN030 (Tunitas Creek at Tunitas Creek Rd & Lobitos Creek Cutoff).

Temporal Representation:

The samples were collected between the dates of 2019-07-31 and 2019-07-31

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 151034, Ammonia	Region 2
Tunitas Creek (San Mateo)

LOE ID:

279644

Pollutant:

Ammonia (Unionized)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202R00488 (Tunitas Creek Road and Lobitos Cut-off Rd).

Temporal Representation:

The samples were collected between the dates of 2016-05-10 and 2016-05-10

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 151034, Ammonia	Region 2
Tunitas Creek (San Mateo)

LOE ID:

278984

Pollutant:

Ammonia (Unionized)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN040 (Tunitas Creek along Rings Gulch).

Temporal Representation:

The samples were collected between the dates of 2019-07-31 and 2019-07-31

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 151034, Ammonia	Region 2
Tunitas Creek (San Mateo)

LOE ID:

280157

Pollutant:

Ammonia (Unionized)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN600 (Tunitas Creek - 1.0mi upstream of confluence with East Fork; 202R00376).

Temporal Representation:

The samples were collected between the dates of 2014-05-12 and 2014-05-12

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 151034, Ammonia	Region 2
Tunitas Creek (San Mateo)

LOE ID:

279147

Pollutant:

Ammonia (Unionized)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202R00488 (Tunitas Creek Road and Lobitos Cut-off Rd).

Temporal Representation:

The samples were collected between the dates of 2016-05-10 and 2016-05-10

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 151034, Ammonia	Region 2
Tunitas Creek (San Mateo)

LOE ID:

279594

Pollutant:

Ammonia (Unionized)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN040 (Tunitas Creek along Rings Gulch).

Temporal Representation:

The samples were collected between the dates of 2019-07-31 and 2019-07-31

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 151034, Ammonia	Region 2
Tunitas Creek (San Mateo)

LOE ID:

278405

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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 BASMAA RMC Monitoring in WY2019 data for Tunitas Creek (San Mateo) 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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN040 (Tunitas Creek along Rings Gulch).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-07-31

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 151034, Ammonia	Region 2
Tunitas Creek (San Mateo)

LOE ID:

278498

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:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

2018 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN600 (Tunitas Creek - 1.0mi upstream of confluence with East Fork; 202R00376).

Temporal Representation:

The samples were collected between the dates of 2014-05-12 and 2014-05-12

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 151034, Ammonia	Region 2
Tunitas Creek (San Mateo)

LOE ID:

278622

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN040 (Tunitas Creek along Rings Gulch).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-07-31

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 151034, Ammonia	Region 2
Tunitas Creek (San Mateo)

LOE ID:

278407

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN600 (Tunitas Creek - 1.0mi upstream of confluence with East Fork; 202R00376).

Temporal Representation:

The samples were collected between the dates of 2014-05-12 and 2014-05-12

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 151034, Ammonia	Region 2
Tunitas Creek (San Mateo)

LOE ID:

277980

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN600 (Tunitas Creek - 1.0mi upstream of confluence with East Fork; 202R00376).

Temporal Representation:

The samples were collected between the dates of 2014-05-12 and 2014-05-12

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 151034, Ammonia	Region 2
Tunitas Creek (San Mateo)

LOE ID:

277979

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN030 (Tunitas Creek at Tunitas Creek Rd & Lobitos Creek Cutoff).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-07-31

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 151034, Ammonia	Region 2
Tunitas Creek (San Mateo)

LOE ID:

278178

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202R00488 (Tunitas Creek Road and Lobitos Cut-off Rd).

Temporal Representation:

The samples were collected between the dates of 2016-05-10 and 2016-05-10

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 151034, Ammonia	Region 2
Tunitas Creek (San Mateo)

LOE ID:

278693

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

2018 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN030 (Tunitas Creek at Tunitas Creek Rd & Lobitos Creek Cutoff).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-07-31

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 151034, Ammonia	Region 2
Tunitas Creek (San Mateo)

LOE ID:

278740

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

2018 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN040 (Tunitas Creek along Rings Gulch).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-07-31

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 151034, Ammonia	Region 2
Tunitas Creek (San Mateo)

LOE ID:

278406

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN030 (Tunitas Creek at Tunitas Creek Rd & Lobitos Creek Cutoff).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-07-31

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan


DECISION ID	151713	Region 2
Tunitas Creek (San Mateo)

Pollutant:	Benthic Community Effects
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:	Benthic Community Effects are being considered for placement on the CWA section 303(d) List under sections 3.9 of the Listing Policy. Under section 3.9, additional lines of evidence (LOEs) associating the Benthic Community Effects decision with a water or sediment concentration of pollutants other than benthic-macroinvertebrate bioassessment or habitat assessment LOEs are necessary to place a water body on the 303(d) List for Benthic Community Effects. Two line(s) of evidence evaluating benthic-macroinvertebrate bioassessment data is/are available in the administrative record to assess this indicator. One of two benthic-macroinvertebrate samples exceed the California Stream Condition Index (CSCI) impairment threshold. However, a minimum of two benthic-macroinvertebrate samples are needed to assess listing status. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing Benthic Community Effects in this waterbody segment 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. One of two benthic-macroinvertebrate bioassessment samples had CSCI scores below 0.79. The available information is insufficient to determine whether the waterbody/pollutant combination should be placed on the 303(d) List of impaired waters at this time. 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 151713, Benthic Community Effects	Region 2
Tunitas Creek (San Mateo)

LOE ID:

307051

Pollutant:

Benthic-Macroinvertebrate Bioassessments

LOE Subgroup:

Population/Community Degradation

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Benthic macroinvertebrate surveys

Data Used to Assess Water Quality:

Water Board staff assessed data for 202R00488 to determine beneficial use support and the results are as follows: 1 of 1 samples exceeded the threshold. CSCI scores were from 0.548032 to 0.548032.

Data Reference:

California Stream Condition Index (CSCI) Scores for the 2024 Integrated Report for Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce significant alterations in population or community ecology or receiving water biota. In addition, the health and life history characteristics of aquatic organisms in waters affected by controllable water quality factors shall not differ significantly from those for the same waters in areas unaffected by controllable water quality factors.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rehn, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.Â

Guideline Reference:

Bioassessment in complex environments: designing an index for consistent meaning in different settings

Spatial Representation:

Samples were collected from station 202R00488.

Temporal Representation:

Samples were collected from 5/10/2016 to 5/10/2016.

Environmental Conditions:

QAPP Information:

Data were collected according to BASMAA Regional Monitoring Coalition sampling protocols.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 151713, Benthic Community Effects	Region 2
Tunitas Creek (San Mateo)

LOE ID:

307044

Pollutant:

Benthic-Macroinvertebrate Bioassessments

LOE Subgroup:

Population/Community Degradation

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Benthic macroinvertebrate surveys

Data Used to Assess Water Quality:

Water Board staff assessed data for 202TUN600 to determine beneficial use support and the results are as follows: 0 of 1 samples exceeded the threshold. CSCI scores were from 0.900466495 to 0.900466495.

Data Reference:

California Stream Condition Index (CSCI) Scores for the 2024 Integrated Report for Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Bioassessment in complex environments: designing an index for consistent meaning in different settings

Spatial Representation:

Samples were collected from station 202TUN600.

Temporal Representation:

Samples were collected from 5/12/2014 to 5/12/2014.

Environmental Conditions:

QAPP Information:

Data were collected using Surface Water Ambient Monitoring Program protocols

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.


DECISION ID	143889	Region 2
Tunitas Creek (San Mateo)

Pollutant:	Chloride
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:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.

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 143889, Chloride	Region 2
Tunitas Creek (San Mateo)

LOE ID:

281787

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The chloride criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 230000 ug/L (230 mg/L)(USEPA National Recommended Water Quality Criteria, 2006).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN030 (Tunitas Creek at Tunitas Creek Rd & Lobitos Creek Cutoff).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-05-14

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 143889, Chloride	Region 2
Tunitas Creek (San Mateo)

LOE ID:

281633

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.22 Constituents of Concern for Municipal and Agricultural Water Supplies states: At a minimum, surface waters designated for use as agricultural supply (AGR) shall not contain concentrations of constituents in excess of the levels specified in Table 3-6. The limit for chloride is 355.0 mg/l.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN030 (Tunitas Creek at Tunitas Creek Rd & Lobitos Creek Cutoff).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-05-14

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 143889, Chloride	Region 2
Tunitas Creek (San Mateo)

LOE ID:

281299

Pollutant:

Chloride

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The California Secondary Maximum Contaminant Level (SMCL) recommended level for chloride is 250 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: 202TUN030 (Tunitas Creek at Tunitas Creek Rd & Lobitos Creek Cutoff).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-05-14

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 143889, Chloride	Region 2
Tunitas Creek (San Mateo)

LOE ID:

281573

Pollutant:

Chloride

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:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN600 (Tunitas Creek - 1.0mi upstream of confluence with East Fork; 202R00376).

Temporal Representation:

The samples were collected between the dates of 2014-05-12 and 2014-05-12

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 143889, Chloride	Region 2
Tunitas Creek (San Mateo)

LOE ID:

280973

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN030 (Tunitas Creek at Tunitas Creek Rd & Lobitos Creek Cutoff).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-05-14

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 143889, Chloride	Region 2
Tunitas Creek (San Mateo)

LOE ID:

281280

Pollutant:

Chloride

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The California Secondary Maximum Contaminant Level (SMCL) recommended level for chloride is 250 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: 202R00488 (Tunitas Creek Road and Lobitos Cut-off Rd).

Temporal Representation:

The samples were collected between the dates of 2016-05-10 and 2016-05-10

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 143889, Chloride	Region 2
Tunitas Creek (San Mateo)

LOE ID:

281697

Pollutant:

Chloride

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:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The California Secondary Maximum Contaminant Level (SMCL) recommended level for chloride is 250 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: 202TUN600 (Tunitas Creek - 1.0mi upstream of confluence with East Fork; 202R00376).

Temporal Representation:

The samples were collected between the dates of 2014-05-12 and 2014-05-12

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 143889, Chloride	Region 2
Tunitas Creek (San Mateo)

LOE ID:

281639

Pollutant:

Chloride

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:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN600 (Tunitas Creek - 1.0mi upstream of confluence with East Fork; 202R00376).

Temporal Representation:

The samples were collected between the dates of 2014-05-12 and 2014-05-12

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 143889, Chloride	Region 2
Tunitas Creek (San Mateo)

LOE ID:

281675

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202R00488 (Tunitas Creek Road and Lobitos Cut-off Rd).

Temporal Representation:

The samples were collected between the dates of 2016-05-10 and 2016-05-10

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 143889, Chloride	Region 2
Tunitas Creek (San Mateo)

LOE ID:

281298

Pollutant:

Chloride

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The California Secondary Maximum Contaminant Level (SMCL) recommended level for chloride is 250 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: 202TUN040 (Tunitas Creek along Rings Gulch).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-05-14

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 143889, Chloride	Region 2
Tunitas Creek (San Mateo)

LOE ID:

281447

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN040 (Tunitas Creek along Rings Gulch).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-05-14

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 143889, Chloride	Region 2
Tunitas Creek (San Mateo)

LOE ID:

281574

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202R00488 (Tunitas Creek Road and Lobitos Cut-off Rd).

Temporal Representation:

The samples were collected between the dates of 2016-05-10 and 2016-05-10

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 143889, Chloride	Region 2
Tunitas Creek (San Mateo)

LOE ID:

281753

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN600 (Tunitas Creek - 1.0mi upstream of confluence with East Fork; 202R00376).

Temporal Representation:

The samples were collected between the dates of 2014-05-12 and 2014-05-12

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 143889, Chloride	Region 2
Tunitas Creek (San Mateo)

LOE ID:

281635

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN040 (Tunitas Creek along Rings Gulch).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-05-14

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 143889, Chloride	Region 2
Tunitas Creek (San Mateo)

LOE ID:

280977

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202R00488 (Tunitas Creek Road and Lobitos Cut-off Rd).

Temporal Representation:

The samples were collected between the dates of 2016-05-10 and 2016-05-10

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 143889, Chloride	Region 2
Tunitas Creek (San Mateo)

LOE ID:

281815

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN040 (Tunitas Creek along Rings Gulch).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-05-14

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan


DECISION ID	143890	Region 2
Tunitas Creek (San Mateo)

Pollutant:	Chlorine
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:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available. Although there was a sufficient number of samples to assess total chlorine, this water body was given a use rating of Insufficient Information and a Do Not List decision. First, data were collected with field instruments that do not have the sensitivity to detect low levels of total chlorine to assess the freshwater water quality objectives of 11 ug/L and 19 ug/L. Secondly, most of the data were collected only once for a given site, and the data were not collected with the purpose of assessing chlorine levels in the water body. A more appropriate sampling to determine water quality impacts of chlorine might be conducted for future Integrated Report assessments.

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 the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 143890, Chlorine	Region 2
Tunitas Creek (San Mateo)

LOE ID:

282299

Pollutant:

Chlorine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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 BASMAA RMC Monitoring in WY2019 data for Tunitas Creek (San Mateo) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chlorine, Total Residual.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN030 (Tunitas Creek at Tunitas Creek Rd & Lobitos Creek Cutoff).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-05-14

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 143890, Chlorine	Region 2
Tunitas Creek (San Mateo)

LOE ID:

282066

Pollutant:

Chlorine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN040 (Tunitas Creek along Rings Gulch).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-05-14

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 143890, Chlorine	Region 2
Tunitas Creek (San Mateo)

LOE ID:

282302

Pollutant:

Chlorine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN030 (Tunitas Creek at Tunitas Creek Rd & Lobitos Creek Cutoff).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-05-14

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 143890, Chlorine	Region 2
Tunitas Creek (San Mateo)

LOE ID:

282364

Pollutant:

Chlorine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN040 (Tunitas Creek along Rings Gulch).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-05-14

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan


DECISION ID	148719	Region 2
Tunitas Creek (San Mateo)

Pollutant:	Indicator Bacteria
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:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

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 the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 148719, Indicator Bacteria	Region 2
Tunitas Creek (San Mateo)

LOE ID:

299622

Pollutant:

Enterococcus

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

STV

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed ASBS Regional Reference Site Monitoring data for Tunitas Creek (San Mateo) to determine beneficial use support and the results are as follows: 2 of the 4 samples exceeded the Statistical Threshold Value (STV) water quality threshold for Enterococcus. The STV is based on a 10% exceedance rate that is calculated monthly.

Data Reference:

Habitat, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The bacteria water quality objective to protect the REC-1 beneficial use where the salinity is 1 ppth or higher 95 percent or more of the time applies a Statistical Threshold Value to enterococcus of 110 cfu/100 mL, not to be exceeded by more than 10 percent of samples collected within in a calendar month. (ISWEBE 2018)

Objective/Criterion Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s), station(s): 206SAN010-REF (Tunitas Creek - Reference Site Receiving Water).

Temporal Representation:

The samples were collected between the days of 2013-10-15 and 2016-01-05 .

Environmental Conditions:

QAPP Information:

Southern California Coastal Water Research Project. 2008. Assessing Natural Water Quality In Areas Of Special Biological Significance.

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 148719, Indicator Bacteria	Region 2
Tunitas Creek (San Mateo)

LOE ID:

299642

Pollutant:

Fecal Coliform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

90th percentile

Beneficial Use:

Non-Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed ASBS Regional Reference Site Monitoring data for Tunitas Creek (San Mateo) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the water quality threshold for Coliform, Fecal. The water quality threshold is based on a 30-day 90% percentile.

Data Reference:

Habitat, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.1 Bacteria: Table 3-1 provides a summary of the bacterial water quality objectives and identifies the sources of those objectives. The fecal coliform objective for non-contact recreation is a 30-day 90th percentile less than 4000 MPN/100 ML.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s), station(s): 206SAN010-REF (Tunitas Creek - Reference Site Receiving Water).

Temporal Representation:

The samples were collected between the days of 2013-10-15 and 2016-01-05 .

Environmental Conditions:

QAPP Information:

Southern California Coastal Water Research Project. 2008. Assessing Natural Water Quality In Areas Of Special Biological Significance.

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.


DECISION ID	148773	Region 2
Tunitas Creek (San Mateo)

Pollutant:	Nitrogen, Nitrite
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:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

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 the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 148773, Nitrogen, Nitrite	Region 2
Tunitas Creek (San Mateo)

LOE ID:

284989

Pollutant:

Nitrogen, Nitrite

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The California Maximum Contaminant Level for nitrite (as N) is 1.0 mg/L (Title 22 of the California Code of Regulations).

Guideline Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN040 (Tunitas Creek along Rings Gulch).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-07-31

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 148773, Nitrogen, Nitrite	Region 2
Tunitas Creek (San Mateo)

LOE ID:

285079

Pollutant:

Nitrogen, Nitrite

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The California Maximum Contaminant Level for nitrite (as N) is 1.0 mg/L (Title 22 of the California Code of Regulations).

Guideline Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN030 (Tunitas Creek at Tunitas Creek Rd & Lobitos Creek Cutoff).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-07-31

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 148773, Nitrogen, Nitrite	Region 2
Tunitas Creek (San Mateo)

LOE ID:

284841

Pollutant:

Nitrogen, Nitrite

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:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The California Maximum Contaminant Level for nitrite (as N) is 1.0 mg/L (Title 22 of the California Code of Regulations).

Guideline Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN600 (Tunitas Creek - 1.0mi upstream of confluence with East Fork; 202R00376).

Temporal Representation:

The samples were collected between the dates of 2014-05-12 and 2014-05-12

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 148773, Nitrogen, Nitrite	Region 2
Tunitas Creek (San Mateo)

LOE ID:

285013

Pollutant:

Nitrogen, Nitrite

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The California Maximum Contaminant Level for nitrite (as N) is 1.0 mg/L (Title 22 of the California Code of Regulations).

Guideline Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22

Spatial Representation:

The samples were collected at 1 monitoring site: 202R00488 (Tunitas Creek Road and Lobitos Cut-off Rd).

Temporal Representation:

The samples were collected between the dates of 2016-05-10 and 2016-05-10

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan


DECISION ID	143891	Region 2
Tunitas Creek (San Mateo)

Pollutant:	Oxygen, Dissolved
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:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.

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 143891, Oxygen, Dissolved	Region 2
Tunitas Creek (San Mateo)

LOE ID:

285621

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen objectives for waters designated as warm water habitat shall be of a 5.0 mg/l minimum. (Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives.)

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN030 (Tunitas Creek at Tunitas Creek Rd & Lobitos Creek Cutoff).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-07-31

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 143891, Oxygen, Dissolved	Region 2
Tunitas Creek (San Mateo)

LOE ID:

286126

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen objectives for waters designated as warm water habitat shall be of a 5.0 mg/l minimum. (Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives.)

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN040 (Tunitas Creek along Rings Gulch).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-07-31

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 143891, Oxygen, Dissolved	Region 2
Tunitas Creek (San Mateo)

LOE ID:

285304

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen objectives for waters designated as cold water habitat shall be of a 7.0 mg/l minimum. (Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives.)

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN030 (Tunitas Creek at Tunitas Creek Rd & Lobitos Creek Cutoff).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-07-31

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 143891, Oxygen, Dissolved	Region 2
Tunitas Creek (San Mateo)

LOE ID:

285302

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen objectives for waters designated as cold water habitat shall be of a 7.0 mg/l minimum. (Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives.)

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202R00488 (Tunitas Creek Road and Lobitos Cut-off Rd).

Temporal Representation:

The samples were collected between the dates of 2016-05-10 and 2016-05-10

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 143891, Oxygen, Dissolved	Region 2
Tunitas Creek (San Mateo)

LOE ID:

285619

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen objectives for waters designated as warm water habitat shall be of a 5.0 mg/l minimum. (Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives.)

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202R00488 (Tunitas Creek Road and Lobitos Cut-off Rd).

Temporal Representation:

The samples were collected between the dates of 2016-05-10 and 2016-05-10

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 143891, Oxygen, Dissolved	Region 2
Tunitas Creek (San Mateo)

LOE ID:

285303

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen objectives for waters designated as cold water habitat shall be of a 7.0 mg/l minimum. (Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives.)

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN040 (Tunitas Creek along Rings Gulch).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-07-31

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 143891, Oxygen, Dissolved	Region 2
Tunitas Creek (San Mateo)

LOE ID:

285535

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen objectives for waters designated as cold water habitat shall be of a 7.0 mg/l minimum. (Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives.)

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN600 (Tunitas Creek - 1.0mi upstream of confluence with East Fork; 202R00376).

Temporal Representation:

The samples were collected between the dates of 2014-05-12 and 2014-05-12

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 143891, Oxygen, Dissolved	Region 2
Tunitas Creek (San Mateo)

LOE ID:

286129

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen objectives for waters designated as warm water habitat shall be of a 5.0 mg/l minimum. (Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives.)

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN600 (Tunitas Creek - 1.0mi upstream of confluence with East Fork; 202R00376).

Temporal Representation:

The samples were collected between the dates of 2014-05-12 and 2014-05-12

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.


DECISION ID	145376	Region 2
Tunitas Creek (San Mateo)

Pollutant:	Specific Conductivity
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:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.

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 145376, Specific Conductivity	Region 2
Tunitas Creek (San Mateo)

LOE ID:

288281

Pollutant:

Specific Conductivity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.22 Constituents of Concern for Municipal and Agricultural Water Supplies states: At a minimum, surface waters designated for use as municipal supply (MUN) shall not contain concentrations of constituents in excess of the levels specified in Table 3-6. The water quality objective for specific conductivity is 3000 uS/cm.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202R00488 (Tunitas Creek Road and Lobitos Cut-off Rd).

Temporal Representation:

The samples were collected between the dates of 2016-05-10 and 2016-05-10

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 145376, Specific Conductivity	Region 2
Tunitas Creek (San Mateo)

LOE ID:

287942

Pollutant:

Specific Conductivity

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 BASMAA RMC Monitoring in WY2019 data for Tunitas Creek (San Mateo) to determine beneficial use support and results are as follows: 1 of 2 samples exceeded the water quality threshold for SpecificConductivity.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The California Secondary Maximum Contaminant Level recommended level for specific conductance is 900 uS/cm (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: 202TUN030 (Tunitas Creek at Tunitas Creek Rd & Lobitos Creek Cutoff).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-07-31

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 145376, Specific Conductivity	Region 2
Tunitas Creek (San Mateo)

LOE ID:

288341

Pollutant:

Specific Conductivity

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The California Secondary Maximum Contaminant Level recommended level for specific conductance is 900 uS/cm (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: 202TUN040 (Tunitas Creek along Rings Gulch).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-07-31

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 145376, Specific Conductivity	Region 2
Tunitas Creek (San Mateo)

LOE ID:

288189

Pollutant:

Specific Conductivity

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 SWAMP RWB2 Monitoring data for Tunitas Creek (San Mateo) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for SpecificConductivity.

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The California Secondary Maximum Contaminant Level recommended level for specific conductance is 900 uS/cm (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: 202TUN600 (Tunitas Creek - 1.0mi upstream of confluence with East Fork; 202R00376).

Temporal Representation:

The samples were collected between the dates of 2014-05-12 and 2014-05-12

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 145376, Specific Conductivity	Region 2
Tunitas Creek (San Mateo)

LOE ID:

287847

Pollutant:

Specific Conductivity

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The California Secondary Maximum Contaminant Level recommended level for specific conductance is 900 uS/cm (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: 202R00488 (Tunitas Creek Road and Lobitos Cut-off Rd).

Temporal Representation:

The samples were collected between the dates of 2016-05-10 and 2016-05-10

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 145376, Specific Conductivity	Region 2
Tunitas Creek (San Mateo)

LOE ID:

287849

Pollutant:

Specific Conductivity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.22 Constituents of Concern for Municipal and Agricultural Water Supplies states: At a minimum, surface waters designated for use as municipal supply (MUN) shall not contain concentrations of constituents in excess of the levels specified in Table 3-6. The water quality objective for specific conductivity is 3000 uS/cm.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN600 (Tunitas Creek - 1.0mi upstream of confluence with East Fork; 202R00376).

Temporal Representation:

The samples were collected between the dates of 2014-05-12 and 2014-05-12

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 145376, Specific Conductivity	Region 2
Tunitas Creek (San Mateo)

LOE ID:

287939

Pollutant:

Specific Conductivity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.22 Constituents of Concern for Municipal and Agricultural Water Supplies states: At a minimum, surface waters designated for use as municipal supply (MUN) shall not contain concentrations of constituents in excess of the levels specified in Table 3-6. The water quality objective for specific conductivity is 3000 uS/cm.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN040 (Tunitas Creek along Rings Gulch).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-07-31

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 145376, Specific Conductivity	Region 2
Tunitas Creek (San Mateo)

LOE ID:

288429

Pollutant:

Specific Conductivity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.22 Constituents of Concern for Municipal and Agricultural Water Supplies states: At a minimum, surface waters designated for use as municipal supply (MUN) shall not contain concentrations of constituents in excess of the levels specified in Table 3-6. The water quality objective for specific conductivity is 3000 uS/cm.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN030 (Tunitas Creek at Tunitas Creek Rd & Lobitos Creek Cutoff).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-07-31

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan


DECISION ID	143893	Region 2
Tunitas Creek (San Mateo)

Pollutant:	Sulfates
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:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.

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 the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 143893, Sulfates	Region 2
Tunitas Creek (San Mateo)

LOE ID:

288252

Pollutant:

Sulfates

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:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The California Secondary Maximum Contaminant Level recommended level for sulfate is 250 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: 202TUN600 (Tunitas Creek - 1.0mi upstream of confluence with East Fork; 202R00376).

Temporal Representation:

The samples were collected between the dates of 2014-05-12 and 2014-05-12

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.


DECISION ID	143894	Region 2
Tunitas Creek (San Mateo)

Pollutant:	Temperature, water
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:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.

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 143894, Temperature, water	Region 2
Tunitas Creek (San Mateo)

LOE ID:

298822

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Fish Migration

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Temperature objectives for surface waters are specified in the San Francisco Bay Regional Water Quality Control Plan. The following temperature objectives apply to surface waters: The natural receiving water temperature of inland surface 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. The temperature of any cold or warm freshwater habitat shall not be increased by more than 5 degrees F (2.8 degrees C) above natural receiving water temperature.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Scientific literature reviewed by the Washington Department of Ecology and U.S. EPA indicates that stream temperatures higher than 21C are associated with avoidance behavior and migration blockages in steelhead trout.

Guideline Reference:

EPA Region 10 Guidance for Pacific Northwest State and Tribal Temperature Water Quality Standards. EPA 910-B-03-002. Region 10 Office of Water, Seattle, WA

Guideline Reference:

U.S. Environmental Protection Agency (USEPA). 2001. Issue Paper 1: Salmonid Behavior and Water Temperature Prepared as Part of EPA Region 10 Temperature Water Quality Criteria Guidance Development Project. Region 10, Seattle, WA. EPA-910-D-01-001 May 2001.

Guideline Reference:

Washington State Department of Ecology (WDOE). 2002. Evaluating Standards for Protecting Aquatic Life in Washington’s Surface Water Quality Standards: Temperature Criteria. Draft Discussion Paper and Literature Summary. Publication Number 00-10-070.

Guideline Reference:

Beschta RL, Bilby RE, Brown GW, Holtby LB, Hofstra TD. 1987. Stream temperature and aquatic habitat: Fisheries and forestry interactions. In: Salo EO, Cundy TW, eds. Streamside management: forestry and fishery interactions. College of Forest Resources, University of Washington, Seattle. Contribution No. 57. Proceedings of a Symposium held at University of Washington, February 12-14, 1986, pp. 191-231.

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN040 (Tunitas Creek along Rings Gulch).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-07-31

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 143894, Temperature, water	Region 2
Tunitas Creek (San Mateo)

LOE ID:

299031

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Fish Migration

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

EPA Region 10 Guidance for Pacific Northwest State and Tribal Temperature Water Quality Standards. EPA 910-B-03-002. Region 10 Office of Water, Seattle, WA

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202R00488 (Tunitas Creek Road and Lobitos Cut-off Rd).

Temporal Representation:

The samples were collected between the dates of 2016-05-10 and 2016-05-10

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 143894, Temperature, water	Region 2
Tunitas Creek (San Mateo)

LOE ID:

299005

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Fish Migration

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

EPA Region 10 Guidance for Pacific Northwest State and Tribal Temperature Water Quality Standards. EPA 910-B-03-002. Region 10 Office of Water, Seattle, WA

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN030 (Tunitas Creek at Tunitas Creek Rd & Lobitos Creek Cutoff).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-07-31

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 143894, Temperature, water	Region 2
Tunitas Creek (San Mateo)

LOE ID:

288852

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

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:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Temperature objectives for surface waters are specified in the San Francisco Bay Regional Water Quality Control Plan. The following temperature objectives apply to surface waters: “- The natural receiving water temperature of inland surface 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. - The temperature of any cold or warm freshwater habitat shall not be increased by more than 5°F (2.8°C) above natural receiving water temperature.”

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Per Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids (Carter 2008, Moyle 1976, and USEPA 1977), the lethal temperature evaluation guideline for both the steelhead adult migration and holding and the steelhead juvenile growth and rearing life stages is 24°C.

Guideline Reference:

Temperature criteria for freshwater fish: protocol and procedures. Ecological Research Series. EPA-600/3-77-061 (NTIS PB270032). Prepared by W.A. Brungs and B.R. Jones. U.S. Environmental Protection Agency, Washington, D.C

Guideline Reference:

Inland Fishes of California

Guideline Reference:

Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids. Implications for California's North Coast TMDLs. California Regional Water Quality Control Board, North Coast Region

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN600 (Tunitas Creek - 1.0mi upstream of confluence with East Fork; 202R00376).

Temporal Representation:

The samples were collected between the dates of 2014-05-12 and 2014-05-12

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 143894, Temperature, water	Region 2
Tunitas Creek (San Mateo)

LOE ID:

289073

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Temperature objectives for surface waters are specified in the San Francisco Bay Regional Water Quality Control Plan. The following temperature objectives apply to surface waters: “- The natural receiving water temperature of inland surface 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. - The temperature of any cold or warm freshwater habitat shall not be increased by more than 5°F (2.8°C) above natural receiving water temperature.”

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Inland Fishes of California

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN030 (Tunitas Creek at Tunitas Creek Rd & Lobitos Creek Cutoff).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-07-31

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 143894, Temperature, water	Region 2
Tunitas Creek (San Mateo)

LOE ID:

288787

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Temperature objectives for surface waters are specified in the San Francisco Bay Regional Water Quality Control Plan. The following temperature objectives apply to surface waters: “- The natural receiving water temperature of inland surface 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. - The temperature of any cold or warm freshwater habitat shall not be increased by more than 5°F (2.8°C) above natural receiving water temperature.”

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Inland Fishes of California

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202R00488 (Tunitas Creek Road and Lobitos Cut-off Rd).

Temporal Representation:

The samples were collected between the dates of 2016-05-10 and 2016-05-10

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 143894, Temperature, water	Region 2
Tunitas Creek (San Mateo)

LOE ID:

298936

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Fish Migration

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

EPA Region 10 Guidance for Pacific Northwest State and Tribal Temperature Water Quality Standards. EPA 910-B-03-002. Region 10 Office of Water, Seattle, WA

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN600 (Tunitas Creek - 1.0mi upstream of confluence with East Fork; 202R00376).

Temporal Representation:

The samples were collected between the dates of 2014-05-12 and 2014-05-12

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 143894, Temperature, water	Region 2
Tunitas Creek (San Mateo)

LOE ID:

288862

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

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:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Temperature objectives for surface waters are specified in the San Francisco Bay Regional Water Quality Control Plan. The following temperature objectives apply to surface waters: “- The natural receiving water temperature of inland surface 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. - The temperature of any cold or warm freshwater habitat shall not be increased by more than 5°F (2.8°C) above natural receiving water temperature.”

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Inland Fishes of California

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN040 (Tunitas Creek along Rings Gulch).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-07-31

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan


DECISION ID	143895	Region 2
Tunitas Creek (San Mateo)

Pollutant:	Turbidity
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:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.

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 the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 143895, Turbidity	Region 2
Tunitas Creek (San Mateo)

LOE ID:

289892

Pollutant:

Turbidity

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:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The California Secondary Maximum Contaminant Level for turbidity is 5 NTU (California Code of Regulations, Title 22). Calculation of a numeric objective for other beneficial uses requires comparison with upstream or other background data which may not be available as part of the data used for water quality assessment.

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: 202TUN600 (Tunitas Creek - 1.0mi upstream of confluence with East Fork; 202R00376).

Temporal Representation:

The samples were collected between the dates of 2014-05-12 and 2014-05-12

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 143895, Turbidity	Region 2
Tunitas Creek (San Mateo)

LOE ID:

302864

Pollutant:

Turbidity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Turbidities of 40 NTU or greater can cause a reduced foraging efficiency and a shift in prey selection in piscivorous fish (largemouth bass) due to interference with their ability to find prey (Shoup, D.E. and Wahl D.H., 2009). The application of this evaluation guideline was restricted to the dry season (May to October) because runoff and resuspension of fine substrate during storm events may naturally elevate turbidity compared to baseflow conditions. The magnitude and duration of these increases will vary depending on the watershed’s geology and land use and may not represent a chronic turbidity problem. Turbidity is naturally higher in tidal river systems, so sample locations with salinity regimes (i.e., Freshwater or Marine) designated as “Marine” were excluded from this analysis.

Guideline Reference:

The Effects of Turbidity on Prey Selection by Piscivorous Largemouth Bass

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN600 (Tunitas Creek - 1.0mi upstream of confluence with East Fork; 202R00376).

Temporal Representation:

The samples were collected between the dates of 2014-05-12 and 2014-05-12

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 143895, Turbidity	Region 2
Tunitas Creek (San Mateo)

LOE ID:

289626

Pollutant:

Turbidity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

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:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Sigler et al. (1984) states that turbidities of 25 NTUs or greater caused reduction in juvenile salmonid growth due to interference with their ability to find food. The application of this evaluation guideline was restricted to the dry season (May to October) because Coho and steelhead early life stages are present during the dry season and feeding becomes infrequent during the winter months (Moyle 2002). Additionally, runoff and resuspension of fine substrate during storm events may naturally elevate turbidity compared to baseflow conditions. The magnitude and duration of these increases will vary depending on the watershed’s geology and land use and may not represent a chronic turbidity problem. Turbidity is naturally higher in tidal river systems, so sample locations with salinity regimes (i.e., Freshwater or Marine) designated as “Marine” were excluded from this analysis.

Guideline Reference:

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

Guideline Reference:

Inland Fishes of California

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN600 (Tunitas Creek - 1.0mi upstream of confluence with East Fork; 202R00376).

Temporal Representation:

The samples were collected between the dates of 2014-05-12 and 2014-05-12

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.


DECISION ID	143892	Region 2
Tunitas Creek (San Mateo)

Pollutant:	pH
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:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.

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 143892, pH	Region 2
Tunitas Creek (San Mateo)

LOE ID:

286860

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:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.9 pH states: The pH shall not be depressed below 6.5 nor raised above 8.5. This encompasses the pH range usually found in waters within the basin. Controllable water quality factors shall not cause changes greater than 0.5 units in normal ambient pH levels.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202R00488 (Tunitas Creek Road and Lobitos Cut-off Rd).

Temporal Representation:

The samples were collected between the dates of 2016-05-10 and 2016-05-10

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 143892, pH	Region 2
Tunitas Creek (San Mateo)

LOE ID:

287117

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:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.22 Constituents of Concern for Municipal and Agricultural Water Supplies states: At a minimum, surface waters designated for use as municipal supply (MUN) shall not contain concentrations of constituents in excess of the levels specified in Table 3-5. The limit for pH ranges from 6-8.5.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN030 (Tunitas Creek at Tunitas Creek Rd & Lobitos Creek Cutoff).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-07-31

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 143892, pH	Region 2
Tunitas Creek (San Mateo)

LOE ID:

287446

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:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN600 (Tunitas Creek - 1.0mi upstream of confluence with East Fork; 202R00376).

Temporal Representation:

The samples were collected between the dates of 2014-05-12 and 2014-05-12

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 143892, pH	Region 2
Tunitas Creek (San Mateo)

LOE ID:

287263

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:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN030 (Tunitas Creek at Tunitas Creek Rd & Lobitos Creek Cutoff).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-07-31

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 143892, pH	Region 2
Tunitas Creek (San Mateo)

LOE ID:

287443

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN030 (Tunitas Creek at Tunitas Creek Rd & Lobitos Creek Cutoff).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-07-31

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 143892, pH	Region 2
Tunitas Creek (San Mateo)

LOE ID:

287157

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:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.22 Constituents of Concern for Municipal and Agricultural Water Supplies states: At a minimum, surface waters designated for use as municipal supply (MUN) shall not contain concentrations of constituents in excess of the levels specified in Table 3-5. The limit for pH ranges from 6-8.5.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202R00488 (Tunitas Creek Road and Lobitos Cut-off Rd).

Temporal Representation:

The samples were collected between the dates of 2016-05-10 and 2016-05-10

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 143892, pH	Region 2
Tunitas Creek (San Mateo)

LOE ID:

287116

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:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.22 Constituents of Concern for Municipal and Agricultural Water Supplies states: At a minimum, surface waters designated for use as municipal supply (MUN) shall not contain concentrations of constituents in excess of the levels specified in Table 3-5. The limit for pH ranges from 6-8.5.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN040 (Tunitas Creek along Rings Gulch).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-07-31

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 143892, pH	Region 2
Tunitas Creek (San Mateo)

LOE ID:

286984

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN600 (Tunitas Creek - 1.0mi upstream of confluence with East Fork; 202R00376).

Temporal Representation:

The samples were collected between the dates of 2014-05-12 and 2014-05-12

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 143892, pH	Region 2
Tunitas Creek (San Mateo)

LOE ID:

286862

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:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN040 (Tunitas Creek along Rings Gulch).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-07-31

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 143892, pH	Region 2
Tunitas Creek (San Mateo)

LOE ID:

286754

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202R00488 (Tunitas Creek Road and Lobitos Cut-off Rd).

Temporal Representation:

The samples were collected between the dates of 2016-05-10 and 2016-05-10

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 143892, pH	Region 2
Tunitas Creek (San Mateo)

LOE ID:

286755

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN040 (Tunitas Creek along Rings Gulch).

Temporal Representation:

The samples were collected between the dates of 2019-05-14 and 2019-07-31

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 143892, pH	Region 2
Tunitas Creek (San Mateo)

LOE ID:

287450

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:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.22 Constituents of Concern for Municipal and Agricultural Water Supplies states: At a minimum, surface waters designated for use as municipal supply (MUN) shall not contain concentrations of constituents in excess of the levels specified in Table 3-5. The limit for pH ranges from 6-8.5.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 202TUN600 (Tunitas Creek - 1.0mi upstream of confluence with East Fork; 202R00376).

Temporal Representation:

The samples were collected between the dates of 2014-05-12 and 2014-05-12

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.