Final California 2026 Integrated Report (303(d) List/305(b) Report)

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157946	Region 1
Smith River HU, Rowdy Creek

Pollutant:	1, 1-dichloroethane
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157946, 1, 1-dichloroethane	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324587

Pollutant:

1, 1-dichloroethane

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for 1, 1-Dichloroethane incorporated by reference in the Water Quality Control Plan, North Coast Basin is 0.005 mg/L (Water Quality Control Plan, North Coast Basin).

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157995	Region 1
Smith River HU, Rowdy Creek

Pollutant:	1, 2-Dibromoethane
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157995, 1, 2-Dibromoethane	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324563

Pollutant:

1, 2-Dibromoethane

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 RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dibromoethane, 1,2-. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for ethylene dibromide (EDB) incorporated by reference in the Water Quality Control Plan, North Coast Basin is 0.05 ug/L (Water Quality Control Plan, North Coast Basin).

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157947	Region 1
Smith River HU, Rowdy Creek

Pollutant:	1, 3 -dichlorobenzene
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157947, 1, 3 -dichlorobenzene	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324576

Pollutant:

1, 3 -dichlorobenzene

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 3-Dichlorobenzene criterion for the protection of human health from the consumption of water and organisms is 400 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157947, 1, 3 -dichlorobenzene	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324577

Pollutant:

1, 3 -dichlorobenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 3-Dichlorobenzene criterion for the protection of human health from consumption of organisms only is 2,600 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157948	Region 1
Smith River HU, Rowdy Creek

Pollutant:	1, 4 -dichlorobenzene
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157948, 1, 4 -dichlorobenzene	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324581

Pollutant:

1, 4 -dichlorobenzene

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for 1, 4-Dichlorobenzene incorporated by reference in the Water Quality Control Plan, North Coast Basin is 0.005 mg/L (Water Quality Control Plan, North Coast Basin).

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157948, 1, 4 -dichlorobenzene	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324578

Pollutant:

1, 4 -dichlorobenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 4-Dichlorobenzene criterion for the protection of human health from consumption of organisms only is 2,600 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157935	Region 1
Smith River HU, Rowdy Creek

Pollutant:	1,1,1,2-Tetrachloroethane
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157935, 1,1,1,2-Tetrachloroethane	Region 1
Smith River HU, Rowdy Creek

LOE ID:

327030

Pollutant:

1,1,1,2-Tetrachloroethane

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA Health Advisory for Tetrachloroethane, 1,1,1,2- as a drinking water level with a one in a million cancer risk is 0.001 mg/L.

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157939	Region 1
Smith River HU, Rowdy Creek

Pollutant:	1,1,1-Trichloroethane
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157939, 1,1,1-Trichloroethane	Region 1
Smith River HU, Rowdy Creek

LOE ID:

327163

Pollutant:

1,1,1-Trichloroethane

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for 1, 1, 1-Trichloroethane incorporated by reference in the Water Quality Control Plan, North Coast Basin is 0.2 mg/L (Water Quality Control Plan, North Coast Basin).

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157956	Region 1
Smith River HU, Rowdy Creek

Pollutant:	1,1,2,2-Tetrachloroethane
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157956, 1,1,2,2-Tetrachloroethane	Region 1
Smith River HU, Rowdy Creek

LOE ID:

327033

Pollutant:

1,1,2,2-Tetrachloroethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 1, 2, 2-Tetrachloroethane criterion for the protection of human health from consumption of organisms only is 11 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157956, 1,1,2,2-Tetrachloroethane	Region 1
Smith River HU, Rowdy Creek

LOE ID:

327036

Pollutant:

1,1,2,2-Tetrachloroethane

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 RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Tetrachloroethane, 1,1,2,2-. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 1, 2, 2-Tetrachloroethane criterion for the protection of human health from the consumption of water and organisms is 0.17 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157988	Region 1
Smith River HU, Rowdy Creek

Pollutant:	1,1,2-Trichloroethane
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157988, 1,1,2-Trichloroethane	Region 1
Smith River HU, Rowdy Creek

LOE ID:

327167

Pollutant:

1,1,2-Trichloroethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 1, 2-Trichloroethane criterion for the protection of human health from consumption of organisms only is 42 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157988, 1,1,2-Trichloroethane	Region 1
Smith River HU, Rowdy Creek

LOE ID:

327169

Pollutant:

1,1,2-Trichloroethane

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 1, 2-Trichloroethane criterion for the protection of human health from the consumption of water and organisms is 0.60 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157988, 1,1,2-Trichloroethane	Region 1
Smith River HU, Rowdy Creek

LOE ID:

327168

Pollutant:

1,1,2-Trichloroethane

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Waters shall not contain toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Basin Plan, 2018)

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA National Recommended Water Quality Criteria (Gold Book) for freshwater aquatic life protection, chronic Lowest Observed Effect Level is 9,400 ug/L.

Guideline Reference:

Quality Criteria for Water 1986. United States Environmental Protection Agency. Office of Water. Regulations and Standards. Washington D.C. EPA 440/5-86-001.

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157855	Region 1
Smith River HU, Rowdy Creek

Pollutant:	1,1-Dichloroethylene (DCE)/ Vinylidene 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:	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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157855, 1,1-Dichloroethylene (DCE)/ Vinylidene Chloride	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324601

Pollutant:

1,1-Dichloroethylene (DCE)/ Vinylidene Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 1-Dichloroethylene criterion for the protection of human health from consumption of organisms only is 3.2 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157855, 1,1-Dichloroethylene (DCE)/ Vinylidene Chloride	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324597

Pollutant:

1,1-Dichloroethylene (DCE)/ Vinylidene 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:

Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dichloroethylene, 1,1-. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 1-Dichloroethylene criterion for the protection of human health from the consumption of water and organisms is 0.057 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157971	Region 1
Smith River HU, Rowdy Creek

Pollutant:	1,2,3-Trichloropropane
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157971, 1,2,3-Trichloropropane	Region 1
Smith River HU, Rowdy Creek

LOE ID:

327184

Pollutant:

1,2,3-Trichloropropane

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 RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Trichloropropane, 1,2,3-. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15, Division 4, Article 4, Section 64435 (Tables 2 and 3), and Section 64444.5 (Table 5), and listed in Table 3-2 of this Plan (Water Quality Control Plan, North Coast Basin).

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

California Maximum Contaminant Levels (MCLs) apply to ambient waters under the Basin Plan's 'Chemical Constituents' objective. The California Maximum Contaminant Level for trichloropropane, 1,2,3- is 0.000005 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: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157857	Region 1
Smith River HU, Rowdy Creek

Pollutant:	1,2,4-Trichlorobenzene
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157857, 1,2,4-Trichlorobenzene	Region 1
Smith River HU, Rowdy Creek

LOE ID:

327159

Pollutant:

1,2,4-Trichlorobenzene

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Basin: Waters designated for MUN shall not contain concentrations of chemical constituents in excess of the MCL specified in Title 22 of the California Code of Regulations. The maximum contaminant level listed in Table 64444-A for 1, 2, 4-Trichlorobenzene is 0.005 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157857, 1,2,4-Trichlorobenzene	Region 1
Smith River HU, Rowdy Creek

LOE ID:

327162

Pollutant:

1,2,4-Trichlorobenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Trichlorobenzene, 1,2,4-. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Waters shall not contain toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Basin Plan, 2018)

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA recommended criterion for 1,2,4-trichlorobenzene for the protection of human health from the consumption of organisms only is 0.076 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157863	Region 1
Smith River HU, Rowdy Creek

Pollutant:	1,2,4-Trimethylbenzene
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157863, 1,2,4-Trimethylbenzene	Region 1
Smith River HU, Rowdy Creek

LOE ID:

327194

Pollutant:

1,2,4-Trimethylbenzene

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Drinking water notification levels are published by the Division of Drinking Water and are for chemicals for which there is no drinking water MCL. If a notification level is exceeded, local government notification is required and customer notification is recommended. The criteria for 1,2,4-Trimethylbenzene is 0.33 mg/L.

Guideline Reference:

Drinking Water Notification and Response Levels: An Overview

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157871	Region 1
Smith River HU, Rowdy Creek

Pollutant:	1,2-Dibromo-3-chloropropane (DBCP)
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157871, 1,2-Dibromo-3-chloropropane (DBCP)	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324556

Pollutant:

1,2-Dibromo-3-chloropropane (DBCP)

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 RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dibromo-3-Chloropropane, 1,2-. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for 1, 2-Dibromo-3-Chloropropane(DBCP) incorporated by reference in the Water Quality Control Plan, North Coast Basin is 0.0002 mg/L (Water Quality Control Plan, North Coast Basin).

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157874	Region 1
Smith River HU, Rowdy Creek

Pollutant:	1,2-Dichloroethane
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157874, 1,2-Dichloroethane	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324595

Pollutant:

1,2-Dichloroethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 2-Dichloroethane criterion for the protection of human health from consumption of organisms only is 99 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157874, 1,2-Dichloroethane	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324590

Pollutant:

1,2-Dichloroethane

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 RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dichloroethane, 1,2-. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 2-dichloroethane criterion for the protection of human health from the consumption of water and organisms is 0.38 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157928	Region 1
Smith River HU, Rowdy Creek

Pollutant:	1,2-Dichloroethylene,-trans
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157928, 1,2-Dichloroethylene,-trans	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324607

Pollutant:

1,2-Dichloroethylene,-trans

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 2-trans-dichlorethylene criterion for the protection of human health from consumption of organisms only is 140,000 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157928, 1,2-Dichloroethylene,-trans	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324610

Pollutant:

1,2-Dichloroethylene,-trans

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

California Maximum Contaminant Levels (MCLs) apply to ambient waters under the Basin Plan's 'Chemical Constituents' objective. The CA Primary MCL for trans 1,2-Dichloroethylene is 10 ug/L

Guideline Reference:

California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157877	Region 1
Smith River HU, Rowdy Creek

Pollutant:	1,2-Dichloropropane
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157877, 1,2-Dichloropropane	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324612

Pollutant:

1,2-Dichloropropane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 2-Dichloropropane criterion for the protection of human health from consumption of organisms only is 39 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157877, 1,2-Dichloropropane	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324611

Pollutant:

1,2-Dichloropropane

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 2-Dichloropropane criterion for the protection of human health from the consumption of water and organisms is 0.52 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157963	Region 1
Smith River HU, Rowdy Creek

Pollutant:	1,3,5-Trimethylbenzene
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157963, 1,3,5-Trimethylbenzene	Region 1
Smith River HU, Rowdy Creek

LOE ID:

327198

Pollutant:

1,3,5-Trimethylbenzene

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Drinking Water Notification and Response Levels: An Overview

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157972	Region 1
Smith River HU, Rowdy Creek

Pollutant:	1,3-Dichloropropane
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157972, 1,3-Dichloropropane	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324618

Pollutant:

1,3-Dichloropropane

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for 1, 3-Dichloropropane incorporated by reference in the Water Quality Control Plan, North Coast Basin is 0.5 ug/L (Water Quality Control Plan, North Coast Basin).

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157885	Region 1
Smith River HU, Rowdy Creek

Pollutant:	1,3-Dichloropropene
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157885, 1,3-Dichloropropene	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324624

Pollutant:

1,3-Dichloropropene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 3-dichloropropylene criterion for the protection of human health from the consumption of organisms only is 1,700 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157885, 1,3-Dichloropropene	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324620

Pollutant:

1,3-Dichloropropene

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for 1, 3-Dichloropropene incorporated by reference in the Water Quality Control Plan, North Coast Basin is 0.5 ug/L (Water Quality Control Plan, North Coast Basin).

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157891	Region 1
Smith River HU, Rowdy Creek

Pollutant:	2,2'-Dichlorodiethyl ether
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157891, 2,2'-Dichlorodiethyl ether	Region 1
Smith River HU, Rowdy Creek

LOE ID:

323809

Pollutant:

2,2'-Dichlorodiethyl ether

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 RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bis(2-chloroethyl)ether. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The bis(2-chloroethyl)ether criterion for the protection of human health from the consumption of water and organisms is 0.031 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157891, 2,2'-Dichlorodiethyl ether	Region 1
Smith River HU, Rowdy Creek

LOE ID:

323805

Pollutant:

2,2'-Dichlorodiethyl ether

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bis(2-chloroethyl)ether. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The bis(2-chloroethyl)ether criterion for the protection of human health from consumption of organisms only is 1.4 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157969	Region 1
Smith River HU, Rowdy Creek

Pollutant:	2-Chlorotoluene
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157969, 2-Chlorotoluene	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324138

Pollutant:

2-Chlorotoluene

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

USEPA's Drinking Water Health advisory for life-time exposure to o-chlorotoluene is a concentration of 100 ug/L

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157970	Region 1
Smith River HU, Rowdy Creek

Pollutant:	4-Chlorotoluene
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157970, 4-Chlorotoluene	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324142

Pollutant:

4-Chlorotoluene

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

USEPA's Drinking Water Health advisory for life-time exposure to p-chlorotoluene is a concentration of 100 ug/L

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157984	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Acetone
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157984, Acetone	Region 1
Smith River HU, Rowdy Creek

LOE ID:

322838

Pollutant:

Acetone

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Based on USEPA IRIS reference dose (RfD) as a drinking water level, the drinking water health advisory level for acetone is 6300 ug/L.

Guideline Reference:

Compilation of Water Quality Goals

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157954	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Acrolein
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157954, Acrolein	Region 1
Smith River HU, Rowdy Creek

LOE ID:

322844

Pollutant:

Acrolein

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The acrolein criterion for the protection of human health from consumption of organisms only is 780 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157954, Acrolein	Region 1
Smith River HU, Rowdy Creek

LOE ID:

322847

Pollutant:

Acrolein

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Waters shall not contain toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Basin Plan, 2018)

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA recommended acrolein criterion for the protection of aquatic life in freshwater is 3 ug/L ( 4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157954, Acrolein	Region 1
Smith River HU, Rowdy Creek

LOE ID:

322840

Pollutant:

Acrolein

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Acrolein criterion for the protection of human health from the consumption of water and organisms is 320 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157958	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Acrylonitrile
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157958, Acrylonitrile	Region 1
Smith River HU, Rowdy Creek

LOE ID:

322852

Pollutant:

Acrylonitrile

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 RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Acrylonitrile. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Acrylonitrile criterion for the protection of human health from the consumption of water and organisms is 0.059 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157958, Acrylonitrile	Region 1
Smith River HU, Rowdy Creek

LOE ID:

322853

Pollutant:

Acrylonitrile

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Acrylonitrile. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Acrylonitrile criterion for the protection of human health from consumption of organisms only is 0.66 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157973	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Aldicarb
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	LOE 115104 has been replaced by LOE 348965, LOE 110932 has been replaced by LOE 348947, LOE 104260 has been replaced by LOE 348981, LOE 113815 has been replaced by LOE 348955, LOE 113821 has been replaced by LOE 348983, and LOE 115109 has been replaced by LOE 348967 due to a reassessment of data using the USEPA Aquatic Life Benchmark threshold. 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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157973, Aldicarb	Region 1
Smith River HU, Rowdy Creek

LOE ID:

322857

Pollutant:

Aldicarb

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA Health Advisory for lifetime exposure to aldicarb as a drinking water level is a concentration of 0.007 mg/L.

Guideline Reference:

2018 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157973, Aldicarb	Region 1
Smith River HU, Rowdy Creek

LOE ID:

322862

Pollutant:

Aldicarb

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 SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldicarb. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for aldicarb is the USEPA Aquatic Life Benchmark of 0.46 ug/L for a fish (chronic).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

Line of Evidence (LOE) for Decision ID 157973, Aldicarb	Region 1
Smith River HU, Rowdy Creek

LOE ID:

107369

Pollutant:

Aldicarb

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for aldicarb incorporated by reference in the Water Quality Control Plan, North Coast Basin is 3 ug/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157973, Aldicarb	Region 1
Smith River HU, Rowdy Creek

LOE ID:

113816

Pollutant:

Aldicarb

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 RWB1 Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Aldicarb.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for aldicarb incorporated by reference in the Water Quality Control Plan, North Coast Basin is 3 ug/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0129)

Temporal Representation:

The samples were collected between the dates of 2013-08-07 and 2013-08-07

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157973, Aldicarb	Region 1
Smith River HU, Rowdy Creek

LOE ID:

104216

Pollutant:

Aldicarb

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for aldicarb incorporated by reference in the Water Quality Control Plan, North Coast Basin is 3 ug/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2015-03-23 and 2015-03-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157973, Aldicarb	Region 1
Smith River HU, Rowdy Creek

LOE ID:

115107

Pollutant:

Aldicarb

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for aldicarb incorporated by reference in the Water Quality Control Plan, North Coast Basin is 3 ug/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157973, Aldicarb	Region 1
Smith River HU, Rowdy Creek

LOE ID:

113823

Pollutant:

Aldicarb

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 RWB1 Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Aldicarb.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for aldicarb incorporated by reference in the Water Quality Control Plan, North Coast Basin is 3 ug/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2013-10-01 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157973, Aldicarb	Region 1
Smith River HU, Rowdy Creek

LOE ID:

102707

Pollutant:

Aldicarb

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for aldicarb incorporated by reference in the Water Quality Control Plan, North Coast Basin is 3 ug/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2015-03-23 and 2015-03-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157973, Aldicarb	Region 1
Smith River HU, Rowdy Creek

LOE ID:

348955

Pollutant:

Aldicarb

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for aldicarb is the USEPA Aquatic Life Benchmark of 0.46 ug/L for a fish (chronic).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW0129 (Rowdy Creek above Smith River).

Temporal Representation:

The samples were collected between the dates of 2013-08-07 and 2013-08-07

Environmental Conditions:

QAPP Information:

Generic SWAMP QAPrP

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

Line of Evidence (LOE) for Decision ID 157973, Aldicarb	Region 1
Smith River HU, Rowdy Creek

LOE ID:

348967

Pollutant:

Aldicarb

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 SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Aldicarb.

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for aldicarb is the USEPA Aquatic Life Benchmark of 0.46 ug/L for a fish (chronic).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW0319 (Rowdy Creek at Alexander Access).

Temporal Representation:

The samples were collected between the dates of 2015-03-11 and 2015-03-23

Environmental Conditions:

QAPP Information:

Generic SWAMP QAPrP

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

Line of Evidence (LOE) for Decision ID 157973, Aldicarb	Region 1
Smith River HU, Rowdy Creek

LOE ID:

348947

Pollutant:

Aldicarb

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for aldicarb is the USEPA Aquatic Life Benchmark of 0.46 ug/L for a fish (chronic).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Generic SWAMP QAPrP

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

Line of Evidence (LOE) for Decision ID 157973, Aldicarb	Region 1
Smith River HU, Rowdy Creek

LOE ID:

348981

Pollutant:

Aldicarb

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for aldicarb is the USEPA Aquatic Life Benchmark of 0.46 ug/L for a fish (chronic).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2015-03-12 and 2015-03-23

Environmental Conditions:

QAPP Information:

Generic SWAMP QAPrP

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

Line of Evidence (LOE) for Decision ID 157973, Aldicarb	Region 1
Smith River HU, Rowdy Creek

LOE ID:

348983

Pollutant:

Aldicarb

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for aldicarb is the USEPA Aquatic Life Benchmark of 0.46 ug/L for a fish (chronic).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2013-10-01 and 2013-11-05

Environmental Conditions:

QAPP Information:

Generic SWAMP QAPrP

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

Line of Evidence (LOE) for Decision ID 157973, Aldicarb	Region 1
Smith River HU, Rowdy Creek

LOE ID:

348976

Pollutant:

Aldicarb

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for aldicarb is the USEPA Aquatic Life Benchmark of 0.46 ug/L for a fish (chronic).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW0319 (Rowdy Creek at Alexander Access).

Temporal Representation:

The samples were collected between the dates of 2013-11-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Generic SWAMP QAPrP

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

Line of Evidence (LOE) for Decision ID 157973, Aldicarb	Region 1
Smith River HU, Rowdy Creek

LOE ID:

348965

Pollutant:

Aldicarb

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for aldicarb is the USEPA Aquatic Life Benchmark of 0.46 ug/L for a fish (chronic).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW0319 (Rowdy Creek at Alexander Access).

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Generic SWAMP QAPrP

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .


DECISION ID	157975	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Aldrin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID:

108660

Pollutant:

Aldrin

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 RWB1 Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. The established numeric criteria for aldrin to protect of human health from the consumption of water and organisms is 0.00013 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 1 station(s) (Station Code(s) 103RW0319).

Temporal Representation:

Date for this waterbody was collected over the date range 2013-11-05 to 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID:

115073

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. The established numeric criteria for aldrin criteria for the protection of human health from consumption of organisms only is 0.00014 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 1 station(s) (Station Code(s) 103RW0319).

Temporal Representation:

Date for this waterbody was collected over the date range 2015-06-23 to 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID:

322877

Pollutant:

Aldrin

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 from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The aldrin criterion maximum concentration (expressed as a 1-day average) to protect aquatic life in freshwater is 1.5 ug/L. The criterion of 3 ug/L provided in the California Toxics Rule is an instantaneous maximum concentration and was divided by 2 in order to better represent a criterion maximum concentration (CMC) value as specified in footnote (g) of Table (b)(1) of the California Toxics Rule (2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID:

322872

Pollutant:

Aldrin

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 RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. The established numeric criterion for aldrin to protect of human health from the consumption of water and organisms is 0.00013 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID:

108915

Pollutant:

Aldrin

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. The established numeric criteria for aldrin to protect aquatic life in freshwater as criterion maximum concentration is 3 ug/L . This established criteria was divided by 2 in order to better represent a CMC value as specified in footnote g of Table (b)(1) of the California Toxics Rule, 2000.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2013-10-01 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID:

108684

Pollutant:

Aldrin

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. The established numeric criteria for aldrin to protect aquatic life in freshwater as criterion maximum concentration is 3 ug/L . This established criteria was divided by 2 in order to better represent a CMC value as specified in footnote g of Table (b)(1) of the California Toxics Rule, 2000.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID:

105825

Pollutant:

Aldrin

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. The established numeric criteria for aldrin to protect aquatic life in freshwater as criterion maximum concentration is 3 ug/L . This established criteria was divided by 2 in order to better represent a CMC value as specified in footnote g of Table (b)(1) of the California Toxics Rule, 2000.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2013-11-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID:

104220

Pollutant:

Aldrin

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. The established numeric criteria for aldrin to protect aquatic life in freshwater as criterion maximum concentration is 3 ug/L . This established criteria was divided by 2 in order to better represent a CMC value as specified in footnote g of Table (b)(1) of the California Toxics Rule, 2000.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID:

113824

Pollutant:

Aldrin

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. The established numeric criteria for aldrin to protect aquatic life in freshwater as criterion maximum concentration is 3 ug/L . This established criteria was divided by 2 in order to better represent a CMC value as specified in footnote g of Table (b)(1) of the California Toxics Rule, 2000.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0129)

Temporal Representation:

The samples were collected between the dates of 2013-08-07 and 2013-08-07

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID:

322867

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. The established numeric criterion for aldrin criteria for the protection of human health from consumption of organisms only is 0.00014 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID:

108659

Pollutant:

Aldrin

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 1 station(s) (Station Code(s) 103RW0129).

Temporal Representation:

Date for this waterbody was collected over the date range 2013-08-07 to 2013-08-07

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID:

104179

Pollutant:

Aldrin

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 RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 1 station(s) (Station Code(s) 103RW1599).

Temporal Representation:

Date for this waterbody was collected over the date range 2015-06-23 to 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID:

106469

Pollutant:

Aldrin

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 RWB1 Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 1 station(s) (Station Code(s) 103RW1599).

Temporal Representation:

Date for this waterbody was collected over the date range 2013-10-01 to 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID:

113789

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB1 Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. The established numeric criteria for aldrin criteria for the protection of human health from consumption of organisms only is 0.00014 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 1 station(s) (Station Code(s) 103RW1599).

Temporal Representation:

Date for this waterbody was collected over the date range 2013-10-01 to 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID:

110335

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. The established numeric criteria for aldrin criteria for the protection of human health from consumption of organisms only is 0.00014 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 1 station(s) (Station Code(s) 103RW1599).

Temporal Representation:

Date for this waterbody was collected over the date range 2015-06-23 to 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID:

113787

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. The established numeric criteria for aldrin criteria for the protection of human health from consumption of organisms only is 0.00014 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 1 station(s) (Station Code(s) 103RW0319).

Temporal Representation:

Date for this waterbody was collected over the date range 2013-11-05 to 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID:

113785

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. The established numeric criteria for aldrin criteria for the protection of human health from consumption of organisms only is 0.00014 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 1 station(s) (Station Code(s) 103RW0129).

Temporal Representation:

Date for this waterbody was collected over the date range 2013-08-07 to 2013-08-07

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID:

104176

Pollutant:

Aldrin

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 RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 1 station(s) (Station Code(s) 103RW0319).

Temporal Representation:

Date for this waterbody was collected over the date range 2015-06-23 to 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	157977	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Alkalinity as CaCO3
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157977, Alkalinity as CaCO3	Region 1
Smith River HU, Rowdy Creek

LOE ID:

102230

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2013-11-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157977, Alkalinity as CaCO3	Region 1
Smith River HU, Rowdy Creek

LOE ID:

115962

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:

Water Board staff assessed SWAMP Reference Condition Management Plan data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Alkalinity as CaCO3.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Reference Condition Management Plan .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RDCBCC)

Temporal Representation:

The samples were collected between the dates of 2011-07-21 and 2011-07-21

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157977, Alkalinity as CaCO3	Region 1
Smith River HU, Rowdy Creek

LOE ID:

104243

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157977, Alkalinity as CaCO3	Region 1
Smith River HU, Rowdy Creek

LOE ID:

102607

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157977, Alkalinity as CaCO3	Region 1
Smith River HU, Rowdy Creek

LOE ID:

102232

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2013-10-01 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157977, Alkalinity as CaCO3	Region 1
Smith River HU, Rowdy Creek

LOE ID:

102228

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0129)

Temporal Representation:

The samples were collected between the dates of 2013-08-07 and 2013-08-07

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157977, Alkalinity as CaCO3	Region 1
Smith River HU, Rowdy Creek

LOE ID:

322998

Pollutant:

Alkalinity as CaCO3

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:

Benthic, Field, Habitat, Tissue, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

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: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2020-01-25 and 2021-10-25

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Benthic, Field, Habitat, Tissue, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157977, Alkalinity as CaCO3	Region 1
Smith River HU, Rowdy Creek

LOE ID:

323092

Pollutant:

Alkalinity as CaCO3

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

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: 103RW2000 (Rowdy Creek at Highway 101).

Temporal Representation:

The samples were collected between the dates of 2020-01-25 and 2021-10-25

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

Line of Evidence (LOE) for Decision ID 157977, Alkalinity as CaCO3	Region 1
Smith River HU, Rowdy Creek

LOE ID:

104247

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2015-03-23 and 2015-03-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157977, Alkalinity as CaCO3	Region 1
Smith River HU, Rowdy Creek

LOE ID:

112293

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Reference Condition Management Plan .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RDCBCC)

Temporal Representation:

The samples were collected between the dates of 2011-07-21 and 2011-07-21

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157977, Alkalinity as CaCO3	Region 1
Smith River HU, Rowdy Creek

LOE ID:

104246

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2015-03-23 and 2015-03-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	157848	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Allethrin
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157848, Allethrin	Region 1
Smith River HU, Rowdy Creek

LOE ID:

323152

Pollutant:

Allethrin

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 from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for Allethrin is the USEPA Aquatic Life Benchmark of 1.05 ug/L for an invertebrate (acute).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157945	Region 1
Smith River HU, Rowdy Creek

Pollutant:	1, 1, 2-trichloro-1, 2, 2-trifluoroethane
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157945, 1, 1, 2-trichloro-1, 2, 2-trifluoroethane	Region 1
Smith River HU, Rowdy Creek

LOE ID:

327156

Pollutant:

1, 1, 2-trichloro-1, 2, 2-trifluoroethane

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157946	Region 1
Smith River HU, Rowdy Creek

Pollutant:	1, 1-dichloroethane
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157946, 1, 1-dichloroethane	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324587

Pollutant:

1, 1-dichloroethane

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .


DECISION ID	102624	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Aluminum
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3 of the Listing Policy. Under section 3 a single line of evidence are necessary to assess listing status. Five lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of the samples exceeded the objective and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

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

Listing Extent:

Line of Evidence (LOE) for Decision ID 102624, Aluminum	Region 1
Smith River HU, Rowdy Creek

LOE ID:

104251

Pollutant:

Aluminum

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical co


DECISION ID	157995	Region 1
Smith River HU, Rowdy Creek

Pollutant:	1, 2-Dibromoethane
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157995, 1, 2-Dibromoethane	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324563

Pollutant:

1, 2-Dibromoethane

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 from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Water Quality Control Plan (Basin Plan) for the North Coast Region

nstituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The secondary maximum contaminant level listed in Table 64449-A for Aluminum is 0.2 mg/L.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 102624, Aluminum	Region 1
Smith River HU, Rowdy Creek

LOE ID:

104252

Pollutant:

Aluminum

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The secondary maximum contaminant level listed in Table 64449-A for Aluminum is 0.2 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 102624, Aluminum	Region 1
Smith River HU, Rowdy Creek

LOE ID:

115143

Pollutant:

Aluminum

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 102624, Aluminum	Region 1
Smith River HU, Rowdy Creek

LOE ID:

104249

Pollutant:

Aluminum

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 102624, Aluminum	Region 1
Smith River HU, Rowdy Creek

LOE ID:

103515

Pollutant:

Aluminum

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Reference Condition Management Plan .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RDCBCC)

Temporal Representation:

The samples were collected between the dates of 2011-07-21 and 2011-07-21

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	157947	Region 1
Smith River HU, Rowdy Creek

Pollutant:	1, 3 -dichlorobenzene
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157947, 1, 3 -dichlorobenzene	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324576

Pollutant:

1, 3 -dichlorobenzene

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 from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 3-Dichlorobenzene criterion for the protection of human health from the consumption of water and organisms is 400 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157947, 1, 3 -dichlorobenzene	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324577

Pollutant:

1, 3 -dichlorobenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 3-Dichlorobenzene criterion for the protection of human health from consumption of organisms only is 2,600 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157948	Region 1
Smith River HU, Rowdy Creek

Pollutant:	1, 4 -dichlorobenzene
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157948, 1, 4 -dichlorobenzene	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324581

Pollutant:

1, 4 -dichlorobenzene

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157948, 1, 4 -dichlorobenzene	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324578

Pollutant:

1, 4 -dichlorobenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 4-Dichlorobenzene criterion for the protection of human health from consumption of organisms only is 2,600 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .


DECISION ID	157980	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Ametryn
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157980, Ametryn	Region 1
Smith River HU, Rowdy Creek

LOE ID:

101839

Pollutant:

Ametryn

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA Health Advisory for lifetime exposure to Ametryn as a drinking water level is a concentration of 0.06 mg/L

Guideline Reference:

DECISION ID

157935

Region 1

Smith River HU, Rowdy Creek

Pollutant:	1,1,1,2-Tetrachloroethane
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157935, 1,1,1,2-Tetrachloroethane	Region 1
Smith River HU, Rowdy Creek

LOE ID:

327030

Pollutant:

1,1,1,2-Tetrachloroethane

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 from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA Health Advisory for Tetrachloroethane, 1,1,1,2- as a drinking water level with a one in a million cancer risk is 0.001 mg/L.

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

cords/state_board/2012/ref4281.pdf" >2012 Edition of the Drinking Water Standards and Health Advisories Spatial Representation: The samples were collected at 1 monitoring site(s) (103RW0319) Temporal Representation: The samples were collected between the dates of 2013-11-05 and 2013-11-05 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157980, Ametryn	Region 1
Smith River HU, Rowdy Creek

LOE ID: 101837 Pollutant: Ametryn LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Municipal & Domestic Supply Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Ametryn. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (North Coast Regional Water Quality Control Board). Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: The USEPA Health Advisory for lifetime exposure to Ametryn as a drinking water level is a concentration of 0.06 mg/L Guideline Reference: 2012 Edition of the Drinking Water Standards and Health Advisories Spatial Representation: The samples were collected at 1 monitoring site(s) (103RW0129) Temporal Representation: The samples were collected between the dates of 2013-08-07 and 2013-08-07 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157980, Ametryn	Region 1
Smith River HU, Rowdy Creek

LOE ID: 323265 Pollutant: Ametryn LOE Subgroup: Pollutant-Water Matrix:

DECISION ID

157939

Region 1

Smith River HU, Rowdy Creek

Pollutant:	1,1,1-Trichloroethane
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157939, 1,1,1-Trichloroethane	Region 1
Smith River HU, Rowdy Creek

LOE ID:

327163

Pollutant:

1,1,1-Trichloroethane

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

t" valign="top" width="67%">Water Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ametryn. Data Reference: Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1 SWAMP Data: SWAMP Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan). Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: The evaluation guideline for ametryn is the USEPA Aquatic Life Benchmark of 3.67 ug/L for nonvascular plants. Guideline Reference: OPP Aquatic Life Benchmarks Spatial Representation: The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive). Temporal Representation: The samples were collected between the dates of 2017-06-08 and 2017-06-08 Environmental Conditions: QAPP Information: QAPP for Surface Water Ambient Monitoring Program (SWAMP) QAPP Information Reference(s): SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 157980, Ametryn	Region 1
Smith River HU, Rowdy Creek

LOE ID: 323259 Pollutant: Ametryn LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Municipal & Domestic Supply Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ametryn. Data Reference: Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1 SWAMP Data: SWAMP Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (North Coast Regional Water Quality Control Board). Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: The USEPA Health Advisory for lifetime exposure to ametryn as a drinking water level is a concentration of 0.06 mg/L Guideline Reference:

DECISION ID

157956

Region 1

Smith River HU, Rowdy Creek

Pollutant:	1,1,2,2-Tetrachloroethane
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157956, 1,1,2,2-Tetrachloroethane	Region 1
Smith River HU, Rowdy Creek

LOE ID:

327033

Pollutant:

1,1,2,2-Tetrachloroethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 1, 2, 2-Tetrachloroethane criterion for the protection of human health from consumption of organisms only is 11 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157956, 1,1,2,2-Tetrachloroethane	Region 1
Smith River HU, Rowdy Creek

LOE ID:

327036

Pollutant:

1,1,2,2-Tetrachloroethane

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 RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Tetrachloroethane, 1,1,2,2-. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 1, 2, 2-Tetrachloroethane criterion for the protection of human health from the consumption of water and organisms is 0.17 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

ords/state_board/2012/ref4281.pdf" >2012 Edition of the Drinking Water Standards and Health Advisories Spatial Representation: The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive). Temporal Representation: The samples were collected between the dates of 2017-06-08 and 2017-06-08 Environmental Conditions: QAPP Information: QAPP for Surface Water Ambient Monitoring Program (SWAMP) QAPP Information Reference(s): SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 157980, Ametryn	Region 1
Smith River HU, Rowdy Creek

LOE ID: 112516 Pollutant: Ametryn LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Dissolved Beneficial Use: Municipal & Domestic Supply Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Ametryn. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (North Coast Regional Water Quality Control Board). Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: The USEPA Health Advisory for lifetime exposure to Ametryn as a drinking water level is a concentration of 0.06 mg/L Guideline Reference: 2012 Edition of the Drinking Water Standards and Health Advisories Spatial Representation: The samples were collected at 1 monitoring site(s) (103RW0319) Temporal Representation: The samples were collected between the dates of 2015-06-23 and 2015-06-23 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157980, Ametryn	Region 1
Smith River HU, Rowdy Creek

LOE ID: 104255 Pollutant: Ametryn LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Dissolved Beneficial Use: Municipal & Domestic Supply Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Ametryn. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (North Coast Regional Water Quality Control Board). Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: The USEPA Health Advisory for lifetime exposure to Ametryn as a drinking water level is a concentration of 0.06 mg/L Guideline Reference: 2012 Edition of the Drinking Water Standards and Health Advisories Spatial Representation: The samples were collected at 1 monitoring site(s) (103RW1599) Temporal Representation: The samples were collected between the dates of 2015-06-23 and 2015-06-23 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157980, Ametryn	Region 1
Smith River HU, Rowdy Creek

LOE ID: 101842 Pollutant: Ametryn LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Municipal & Domestic Supply Number of Samples: 2 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Ametryn. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (North Coast Regional Water Quality Control Board). Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: The USEPA Health Advisory for lifetime exposure to Ametryn as a drinking water level is a concentration of 0.06 mg/L Guideline Reference: 2012 Edition of the Drinking Water Standards and Health Advisories Spatial Representation: The samples were collected at 1 monitoring site(s) (103RW1599) Temporal Representation: The samples were collected between the dates of 2013-10-01 and 2013-11-05 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157980, Ametryn	Region 1
Smith River HU, Rowdy Creek

LOE ID: 118951 Pollutant: Ametryn LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Municipal & Domestic Supply Number of Samples: 2 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Ametryn. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (North Coast Regional Water Quality Control Board). Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: The USEPA Health Advisory for lifetime exposure to Ametryn as a drinking water level is a concentration of 0.06 mg/L Guideline Reference: 2012 Edition of the Drinking Water Standards and Health Advisories Spatial Representation: The samples were collected at 1 monitoring site(s) (103RW0319) Temporal Representation: The samples were collected between the dates of 2015-03-11 and 2015-03-23 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157980, Ametryn	Region 1
Smith River HU, Rowdy Creek

LOE ID: 115154 Pollutant: Ametryn LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Municipal & Domestic Supply Number of Samples: 2 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Ametryn. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (North Coast Regional Water Quality Control Board). Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: The USEPA Health Advisory for lifetime exposure to Ametryn as a drinking water level is a concentration of 0.06 mg/L Guideline Reference: 2012 Edition of the Drinking Water Standards and Health Advisories Spatial Representation: The samples were collected at 1 monitoring site(s) (103RW1599) Temporal Representation: The samples were collected between the dates of 2015-03-12 and 2015-03-23 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	157988	Region 1
Smith River HU, Rowdy Creek

Pollutant:	1,1,2-Trichloroethane
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157988, 1,1,2-Trichloroethane	Region 1
Smith River HU, Rowdy Creek

LOE ID:

327167

Pollutant:

1,1,2-Trichloroethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 1, 2-Trichloroethane criterion for the protection of human health from consumption of organisms only is 42 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157988, 1,1,2-Trichloroethane	Region 1
Smith River HU, Rowdy Creek

LOE ID:

327169

Pollutant:

1,1,2-Trichloroethane

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 1, 2-Trichloroethane criterion for the protection of human health from the consumption of water and organisms is 0.60 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157988, 1,1,2-Trichloroethane	Region 1
Smith River HU, Rowdy Creek

LOE ID:

327168

Pollutant:

1,1,2-Trichloroethane

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Waters shall not contain toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Basin Plan, 2018)

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA National Recommended Water Quality Criteria (Gold Book) for freshwater aquatic life protection, chronic Lowest Observed Effect Level is 9,400 ug/L.

Guideline Reference:

Quality Criteria for Water 1986. United States Environmental Protection Agency. Office of Water. Regulations and Standards. Washington D.C. EPA 440/5-86-001.

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157855	Region 1
Smith River HU, Rowdy Creek

Pollutant:	1,1-Dichloroethylene (DCE)/ Vinylidene 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:	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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157855, 1,1-Dichloroethylene (DCE)/ Vinylidene Chloride	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324601

Pollutant:

1,1-Dichloroethylene (DCE)/ Vinylidene Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 1-Dichloroethylene criterion for the protection of human health from consumption of organisms only is 3.2 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157855, 1,1-Dichloroethylene (DCE)/ Vinylidene Chloride	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324597

Pollutant:

1,1-Dichloroethylene (DCE)/ Vinylidene 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:

Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dichloroethylene, 1,1-. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 1-Dichloroethylene criterion for the protection of human health from the consumption of water and organisms is 0.057 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157971	Region 1
Smith River HU, Rowdy Creek

Pollutant:	1,2,3-Trichloropropane
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157971, 1,2,3-Trichloropropane	Region 1
Smith River HU, Rowdy Creek

LOE ID:

327184

Pollutant:

1,2,3-Trichloropropane

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 RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Trichloropropane, 1,2,3-. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

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: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .


DECISION ID	104124	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Aminomethyl Phosphonic Acid (AMPA)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line(s) of evidence are necessary to assess listing status. Five line(s) of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None samples exceeded the objective and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

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

Listing Extent:

Line of Evidence (LOE) for Decision ID 104124, Aminomethyl Phosphonic Acid (AMPA)	Region 1
Smith River HU, Rowdy Creek

LOE ID:

107300

Pollutant:

Aminomethyl Phosphonic Acid (AMPA)

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 SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for AMPA.

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which


DECISION ID	157857	Region 1
Smith River HU, Rowdy Creek

Pollutant:	1,2,4-Trichlorobenzene
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157857, 1,2,4-Trichlorobenzene	Region 1
Smith River HU, Rowdy Creek

LOE ID:

327159

Pollutant:

1,2,4-Trichlorobenzene

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 from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157857, 1,2,4-Trichlorobenzene	Region 1
Smith River HU, Rowdy Creek

LOE ID:

327162

Pollutant:

1,2,4-Trichlorobenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Trichlorobenzene, 1,2,4-. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Waters shall not contain toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Basin Plan, 2018)

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA recommended criterion for 1,2,4-trichlorobenzene for the protection of human health from the consumption of organisms only is 0.076 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Water Quality Control Plan (Basin Plan) for the North Coast Region

produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan).

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for AMPA is the USEPA Aquatic Life Benchmark of 249500 ug/L for a fish (acute).

Guideline Reference:

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2015-03-11 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104124, Aminomethyl Phosphonic Acid (AMPA)	Region 1
Smith River HU, Rowdy Creek

LOE ID:

113308

Pollutant:

Aminomethyl Phosphonic Acid (AMPA)

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for AMPA is the USEPA Aquatic Life Benchmark of 249500 ug/L for a fish (acute).

Guideline Reference:

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2013-11-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104124, Aminomethyl Phosphonic Acid (AMPA)

Region 1 &


DECISION ID	157863	Region 1
Smith River HU, Rowdy Creek

Pollutant:	1,2,4-Trimethylbenzene
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157863, 1,2,4-Trimethylbenzene	Region 1
Smith River HU, Rowdy Creek

LOE ID:

327194

Pollutant:

1,2,4-Trimethylbenzene

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 from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Drinking Water Notification and Response Levels: An Overview

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

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Smith River HU, Rowdy Creek

LOE ID:

114579

Pollutant:

Aminomethyl Phosphonic Acid (AMPA)

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for AMPA is the USEPA Aquatic Life Benchmark of 249500 ug/L for a fish (acute).

Guideline Reference:

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2013-10-01 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104124, Aminomethyl Phosphonic Acid (AMPA)	Region 1
Smith River HU, Rowdy Creek

LOE ID:

102261

Pollutant:

Aminomethyl Phosphonic Acid (AMPA)

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for AMPA is the USEPA Aquatic Life Benchmark of 249500 ug/L for a fish (acute).

Guideline Reference:

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0129)

Temporal Representation:

The samples were collected between the dates of 2013-08-07 and 2013-08-07

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104124, Aminomethyl Phosphonic Acid (AMPA)	Region 1
Smith River HU, Rowdy Creek

LOE ID:

114354

Pollutant:

Aminomethyl Phosphonic Acid (AMPA)

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for AMPA is the USEPA Aquatic Life Benchmark of 249500 ug/L for a fish (acute).

Guideline Reference:

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2015-03-12 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):


DECISION ID	157871	Region 1
Smith River HU, Rowdy Creek

Pollutant:	1,2-Dibromo-3-chloropropane (DBCP)
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157871, 1,2-Dibromo-3-chloropropane (DBCP)	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324556

Pollutant:

1,2-Dibromo-3-chloropropane (DBCP)

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 RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dibromo-3-Chloropropane, 1,2-. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157874	Region 1
Smith River HU, Rowdy Creek

Pollutant:	1,2-Dichloroethane
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157874, 1,2-Dichloroethane	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324595

Pollutant:

1,2-Dichloroethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 2-Dichloroethane criterion for the protection of human health from consumption of organisms only is 99 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157874, 1,2-Dichloroethane	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324590

Pollutant:

1,2-Dichloroethane

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 RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dichloroethane, 1,2-. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 2-dichloroethane criterion for the protection of human health from the consumption of water and organisms is 0.38 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .


DECISION ID	104753	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Ammonia
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Ten lines of evidence are available in the administrative record to assess this pollutant. Zero of seven samples exceed the objective for COLD and zero of 11 samples exceed the objective for MUN. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of seven samples exceed the objective for COLD and zero of 11 samples exceed the objective for MUN. This sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

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

Listing Extent:

Line of Evidence (LOE) for Decision ID 104753, Ammonia	Region 1
Smith River HU, Rowdy Creek

LOE ID:

102251

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA Health Advisory for lifetime exposure to Ammonia as a drinking water level is a concentration of 30 mg/L

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0129)

Temporal Representation:

The samples were collected between the dates of 2013-08-07 and 2013-08-07

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 104753, Ammonia	Region 1
Smith River HU, Rowdy Creek

LOE ID:

104263

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

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(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2015-03-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 104753, Ammonia	Region 1


DECISION ID	157928	Region 1
Smith River HU, Rowdy Creek

Pollutant:	1,2-Dichloroethylene,-trans
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157928, 1,2-Dichloroethylene,-trans	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324607

Pollutant:

1,2-Dichloroethylene,-trans

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

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 from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 2-trans-dichlorethylene criterion for the protection of human health from consumption of organisms only is 140,000 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157928, 1,2-Dichloroethylene,-trans	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324610

Pollutant:

1,2-Dichloroethylene,-trans

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

California Maximum Contaminant Levels (MCLs) apply to ambient waters under the Basin Plan's 'Chemical Constituents' objective. The CA Primary MCL for trans 1,2-Dichloroethylene is 10 ug/L

Guideline Reference:

California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

-color:#CCCCCC; PADDING-RIGHT: 2%; PADDING-LEFT: 0%; FONT-WEIGHT: bold; PADDING-BOTTOM: 3px; WIDTH: 100%; text-align: left; PADDING-TOP: 3px; font-smooth: always">Smith River HU, Rowdy Creek

LOE ID: 104268 Pollutant: Nitrogen, ammonia (Total Ammonia) LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 2 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Ammonia as N. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring . SWAMP Data: 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(s) (103RW1599) Temporal Representation: The samples were collected between the dates of 2015-03-23 and 2015-06-23 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 104753, Ammonia	Region 1
Smith River HU, Rowdy Creek

LOE ID: 101846 Pollutant: Nitrogen, ammonia (Total Ammonia) LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Ammonia as N. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring . SWAMP Data: 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.

DECISION ID

157877

Region 1

Smith River HU, Rowdy Creek

Pollutant:	1,2-Dichloropropane
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157877, 1,2-Dichloropropane	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324612

Pollutant:

1,2-Dichloropropane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 2-Dichloropropane criterion for the protection of human health from consumption of organisms only is 39 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157877, 1,2-Dichloropropane	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324611

Pollutant:

1,2-Dichloropropane

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 2-Dichloropropane criterion for the protection of human health from the consumption of water and organisms is 0.52 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

ign="left" valign="top" width="33%">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(s) (103RW0319) Temporal Representation: The samples were collected between the dates of 2013-11-05 and 2013-11-05 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 104753, Ammonia	Region 1
Smith River HU, Rowdy Creek

LOE ID: 108951 Pollutant: Nitrogen, ammonia (Total Ammonia) LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 2 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Ammonia as N. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring . SWAMP Data: 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(s) (103RW1599) Temporal Representation: The samples were collected between the dates of 2013-10-01 and 2013-11-05 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 104753, Ammonia	Region 1
Smith River HU, Rowdy Creek

LOE ID: 111138 Pollutant: Nitrogen, ammonia (Total Ammonia)

DECISION ID

157963

Region 1

Smith River HU, Rowdy Creek

Pollutant:	1,3,5-Trimethylbenzene
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157963, 1,3,5-Trimethylbenzene	Region 1
Smith River HU, Rowdy Creek

LOE ID:

327198

Pollutant:

1,3,5-Trimethylbenzene

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Drinking Water Notification and Response Levels: An Overview

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157972	Region 1
Smith River HU, Rowdy Creek

Pollutant:	1,3-Dichloropropane
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157972, 1,3-Dichloropropane	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324618

Pollutant:

1,3-Dichloropropane

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

r> LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Municipal & Domestic Supply Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed DFW_ABL_Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Ammonia as N. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for DFW_ABL_Monitoring. SWAMP Data: Non-SWAMP Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (North Coast Regional Water Quality Control Board). Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: The USEPA Health Advisory for lifetime exposure to Ammonia as a drinking water level is a concentration of 30 mg/L Guideline Reference: 2012 Edition of the Drinking Water Standards and Health Advisories Spatial Representation: The samples were collected at 1 monitoring site(s) (103FC1106) Temporal Representation: The samples were collected between the dates of 2014-07-15 and 2014-07-15 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 104753, Ammonia	Region 1
Smith River HU, Rowdy Creek

LOE ID: 102260 Pollutant: Nitrogen, ammonia (Total Ammonia) LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Municipal & Domestic Supply Number of Samples: 2 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Ammonia as N. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (North Coast Regional Water Quality Control Board). Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: The USEPA Health Advisory for lifetime exposure to Ammonia as a drinking water level is a concentration of 30 mg/L Guideline Reference: 2012 Edition of the Drinking Water Standards and Health Advisories Spatial Representation: The samples were collected at 1 monitoring site(s) (103RW1599) Temporal Representation: The samples were collected between the dates of 2013-10-01 and 2013-11-05 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 104753, Ammonia	Region 1
Smith River HU, Rowdy Creek

LOE ID: 104270 Pollutant: Nitrogen, ammonia (Total Ammonia) LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Municipal & Domestic Supply Number of Samples: 3 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Ammonia as N. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (North Coast Regional Water Quality Control Board). Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: The USEPA Health Advisory for lifetime exposure to Ammonia as a drinking water level is a concentration of 30 mg/L Guideline Reference: 2012 Edition of the Drinking Water Standards and Health Advisories Spatial Representation: The samples were collected at 1 monitoring site(s) (103RW1599) Temporal Representation: The samples were collected between the dates of 2015-03-12 and 2015-06-23 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 104753, Ammonia	Region 1
Smith River HU, Rowdy Creek

LOE ID: 118960 Pollutant: Nitrogen, ammonia (Total Ammonia) LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Municipal & Domestic Supply Number of Samples: 3 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Ammonia as N. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (North Coast Regional Water Quality Control Board). Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: The USEPA Health Advisory for lifetime exposure to Ammonia as a drinking water level is a concentration of 30 mg/L Guideline Reference: 2012 Edition of the Drinking Water Standards and Health Advisories Spatial Representation: The samples were collected at 1 monitoring site(s) (103RW0319) Temporal Representation: The samples were collected between the dates of 2015-03-11 and 2015-06-23 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 104753, Ammonia	Region 1
Smith River HU, Rowdy Creek

LOE ID: 101848 Pollutant: Nitrogen, ammonia (Total Ammonia) LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Municipal & Domestic Supply Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Ammonia as N. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (North Coast Regional Water Quality Control Board). Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: The USEPA Health Advisory for lifetime exposure to Ammonia as a drinking water level is a concentration of 30 mg/L Guideline Reference: 2012 Edition of the Drinking Water Standards and Health Advisories Spatial Representation: The samples were collected at 1 monitoring site(s) (103RW0319) Temporal Representation: The samples were collected between the dates of 2013-11-05 and 2013-11-05 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	157885	Region 1
Smith River HU, Rowdy Creek

Pollutant:	1,3-Dichloropropene
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157885, 1,3-Dichloropropene	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324624

Pollutant:

1,3-Dichloropropene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The 1, 3-dichloropropylene criterion for the protection of human health from the consumption of organisms only is 1,700 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157885, 1,3-Dichloropropene	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324620

Pollutant:

1,3-Dichloropropene

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157891	Region 1
Smith River HU, Rowdy Creek

Pollutant:	2,2'-Dichlorodiethyl ether
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157891, 2,2'-Dichlorodiethyl ether	Region 1
Smith River HU, Rowdy Creek

LOE ID:

323809

Pollutant:

2,2'-Dichlorodiethyl ether

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 RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bis(2-chloroethyl)ether. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The bis(2-chloroethyl)ether criterion for the protection of human health from the consumption of water and organisms is 0.031 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157891, 2,2'-Dichlorodiethyl ether	Region 1
Smith River HU, Rowdy Creek

LOE ID:

323805

Pollutant:

2,2'-Dichlorodiethyl ether

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bis(2-chloroethyl)ether. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The bis(2-chloroethyl)ether criterion for the protection of human health from consumption of organisms only is 1.4 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .


DECISION ID	104134	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Anthracene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line(s) of evidence are necessary to assess listing status. Two line(s) of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None samples exceeded the objective and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

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

Listing Extent:

Line of Evidence (LOE) for Decision ID 104134, Anthracene	Region 1
Smith River HU, Rowdy Creek

LOE ID:

121867

Pollutant:

Anthracene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

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 SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Anthracene .

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for Anthrazene from MacDonald et al., 2000a which states that the probable effect concentration for Anthrazene is 845 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 103RW1599.

Temporal Representation:

Data for this waterbody were collected over the date range 2015-06-23 to 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 104134, Anthracene	Region 1
Smith River HU, Rowdy Creek

LOE ID:

121826

Pollutant:

Anthracene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for Anthrazene from MacDonald et al., 2000a which states that the probable effect concentration for Anthrazene is 845 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 103RW0319.

Temporal Representation:

Data for this waterbody were collected over the date range 2015-06-23 to 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	157969	Region 1
Smith River HU, Rowdy Creek

Pollutant:	2-Chlorotoluene
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157969, 2-Chlorotoluene	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324138

Pollutant:

2-Chlorotoluene

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 from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

USEPA's Drinking Water Health advisory for life-time exposure to o-chlorotoluene is a concentration of 100 ug/L

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157970	Region 1
Smith River HU, Rowdy Creek

Pollutant:	4-Chlorotoluene
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157970, 4-Chlorotoluene	Region 1
Smith River HU, Rowdy Creek

LOE ID:

324142

Pollutant:

4-Chlorotoluene

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

USEPA's Drinking Water Health advisory for life-time exposure to p-chlorotoluene is a concentration of 100 ug/L

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitat


DECISION ID	100826	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Arsenic
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line(s) of evidence are necessary to assess listing status. Twelve lines of evidence are available in the administrative record to assess this pollutant. Zero of three sediment and water samples exceed the objective for protection of COLD and none of the sediment samples exhibit toxicity. Zero of three water samples exceed the objective for the protection of MUN. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of three sediment and water samples exceed the objective for protection of COLD and none of the sediment samples exhibit toxicity. Zero of three water samples exceed the objective for the protection of MUN. This sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to SECTION 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

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

Listing Extent:

Line of Evidence (LOE) for Decision ID 100826, Arsenic	Region 1
Smith River HU, Rowdy Creek

LOE ID:

120949

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

0 of the 1 samples collected by SWAMP RWB1 Irrigated Lands Monitoring for Smith River HU, Rowdy Creek exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Survival, Hyalella azteca, for Growth (wt/surv indiv)

Data Reference:


DECISION ID	157984	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Acetone
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157984, Acetone	Region 1
Smith River HU, Rowdy Creek

Municipal & Domestic Supply

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Water Quality Control Plan (Basin Plan) for the North Coast Region

Based on USEPA IRIS reference dose (RfD) as a drinking water level, the drinking water health advisory level for acetone is 6300 ug/L.

Compilation of Water Quality Goals

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

The samples were collected between the dates of 2017-06-08 and 2017-06-08

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

ion cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Water Board(NCRWQCB 2018).

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 stations. Monitoring site(s): ( 103RW1599 )

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23.

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 100826, Arsenic	Region 1
Smith River HU, Rowdy Creek

LOE ID:

121009

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

0 of the 1 samples collected by SWAMP RWB1 Irrigated Lands Monitoring for Smith River HU, Rowdy Creek exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Growth (wt/surv indiv), Hyalella azteca, for Survival

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 stations. Monitoring site(s): ( 103RW0319 )

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23.

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP pro


DECISION ID	157954	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Acrolein
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157954, Acrolein	Region 1
Smith River HU, Rowdy Creek

Commercial or recreational collection of fish, shellfish, or organisms

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

The acrolein criterion for the protection of human health from consumption of organisms only is 780 ug/L (California Toxics Rule, 2000).

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

The samples were collected between the dates of 2017-06-08 and 2017-06-08

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

Line of Evidence (LOE) for Decision ID 157954, Acrolein	Region 1
Smith River HU, Rowdy Creek

Cold Freshwater Habitat

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Waters shall not contain toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Basin Plan, 2018)

Water Quality Control Plan (Basin Plan) for the North Coast Region

The USEPA recommended acrolein criterion for the protection of aquatic life in freshwater is 3 ug/L ( 4-day average).

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

The samples were collected between the dates of 2017-06-08 and 2017-06-08

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

Municipal & Domestic Supply

Line of Evidence (LOE) for Decision ID 157954, Acrolein	Region 1
Smith River HU, Rowdy Creek

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

The Acrolein criterion for the protection of human health from the consumption of water and organisms is 320 ug/L (California Toxics Rule, 2000).

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

The samples were collected between the dates of 2017-06-08 and 2017-06-08

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

gram

Line of Evidence (LOE) for Decision ID 100826, Arsenic	Region 1
Smith River HU, Rowdy Creek

LOE ID:

120948

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

0 of the 1 samples collected by SWAMP RWB1 Monitoring for Smith River HU, Rowdy Creek exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Growth (wt/surv indiv), Hyalella azteca, for Survival

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 stations. Monitoring site(s): ( 103RW0319 )

Temporal Representation:

The samples were collected between the dates of 2013-11-05 and 2013-11-05.

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 100826, Arsenic	Region 1
Smith River HU, Rowdy Creek

LOE ID:

110872

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The maximum contaminant level listed in Table 64431-A for arsenic is 0.010 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 100826, Arsenic	Region 1
Smith River HU, Rowdy Creek

LOE ID:

110877

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The maximum contaminant level listed in Table 64431-A for arsenic is 0.010 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	157958	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Acrylonitrile
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157958, Acrylonitrile	Region 1
Smith River HU, Rowdy Creek

LOE ID:

322852

Pollutant:

Acrylonitrile

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 RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Acrylonitrile. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Acrylonitrile criterion for the protection of human health from the consumption of water and organisms is 0.059 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157958, Acrylonitrile	Region 1
Smith River HU, Rowdy Creek

LOE ID:

322853

Pollutant:

Acrylonitrile

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Acrylonitrile. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Acrylonitrile criterion for the protection of human health from consumption of organisms only is 0.66 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

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Line of Evidence (LOE) for Decision ID 100826, Arsenic

Region 1

Smith River HU, Rowdy Creek

LOE ID: 110058 Pollutant: Arsenic LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Municipal & Domestic Supply Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP Reference Condition Management Plan data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Arsenic. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Reference Condition Management Plan . SWAMP Data: SWAMP Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The maximum contaminant level listed in Table 64431-A for arsenic is 0.010 mg/L. Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: Guideline Reference: Spatial Representation: The samples were collected at 1 monitoring site(s) (103RDCBCC) Temporal Representation: The samples were collected between the dates of 2011-07-21 and 2011-07-21 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 100826, Arsenic	Region 1
Smith River HU, Rowdy Creek

LOE ID: 110874 Pollutant: Arsenic LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Arsenic. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 150 ug/L (California Toxics Rule, 2000). Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency Evaluation Guideline: Guideline Reference: Spatial Representation: The samples were collected at 1 monitoring site(s) (103RW1599) Temporal Representation: The samples were collected between the dates of 2015-06-23 and 2015-06-23 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 100826, Arsenic	Region 1
Smith River HU, Rowdy Creek

LOE ID: 107309 Pollutant: Arsenic LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Arsenic. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 150 ug/L (California Toxics Rule, 2000). Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency Evaluation Guideline: Guideline Reference: Spatial Representation: The samples were collected at 1 monitoring site(s) (103RW0319) Temporal Representation: The samples were collected between the dates of 2015-06-23 and 2015-06-23 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 100826, Arsenic

DECISION ID	157973	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Aldicarb
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	LOE 115104 has been replaced by LOE 348965, LOE 110932 has been replaced by LOE 348947, LOE 104260 has been replaced by LOE 348981, LOE 113815 has been replaced by LOE 348955, LOE 113821 has been replaced by LOE 348983, and LOE 115109 has been replaced by LOE 348967 due to a reassessment of data using the USEPA Aquatic Life Benchmark threshold. 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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157973, Aldicarb	Region 1
Smith River HU, Rowdy Creek

LOE ID:

322857

Pollutant:

Aldicarb

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Region 1

Smith River HU, Rowdy Creek

LOE ID: 122029 Pollutant: Arsenic LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Arsenic . Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan for the North Coast Region). Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for arsenic is 33 mg/Kg dry weight (MacDonald et al. 2000a). Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31 Spatial Representation: Data were collected from 1 station(s). Station Code(s): 103RW0319. Temporal Representation: Data for this waterbody were collected over the date range 2013-11-05 to 2013-11-05 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 100826, Arsenic	Region 1
Smith River HU, Rowdy Creek

LOE ID: 110003 Pollutant: Arsenic LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP Reference Condition Management Plan data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Arsenic. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Reference Condition Management Plan . SWAMP Data: SWAMP Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 150 ug/L (California Toxics Rule, 2000). Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency Evaluation Guideline: Guideline Reference: Spatial Representation: The samples were collected at 1 monitoring site(s) (103RDCBCC) Temporal Representation: The samples were collected between the dates of 2011-07-21 and 2011-07-21 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 100826, Arsenic	Region 1
Smith River HU, Rowdy Creek

LOE ID: 122092 Pollutant: Arsenic LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Arsenic . Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan for the North Coast Region). Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for arsenic is 33 mg/Kg dry weight (MacDonald et al. 2000a). Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31 Spatial Representation: Data were collected from 1 station(s). Station Code(s): 103RW0319. Temporal Representation: Data for this waterbody were collected over the date range 2015-06-23 to 2015-06-23 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 100826, Arsenic	Region 1
Smith River HU, Rowdy Creek

LOE ID: 122094 Pollutant: Arsenic LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Arsenic . Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan for the North Coast Region). Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for arsenic is 33 mg/Kg dry weight (MacDonald et al. 2000a). Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31 Spatial Representation: Data were collected from 1 station(s). Station Code(s): 103RW1599. Temporal Representation: Data for this waterbody were collected over the date range 2015-06-23 to 2015-06-23 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program >Evaluation Guideline: The USEPA Health Advisory for lifetime exposure to aldicarb as a drinking water level is a concentration of 0.007 mg/L. Guideline Reference: 2018 Edition of the Drinking Water Standards and Health Advisories Spatial Representation: The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive). Temporal Representation: The samples were collected between the dates of 2017-06-08 and 2017-06-08 Environmental Conditions: QAPP Information: QAPP for Surface Water Ambient Monitoring Program (SWAMP) QAPP Information Reference(s): SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 157973, Aldicarb	Region 1
Smith River HU, Rowdy Creek

LOE ID: 322862 Pollutant: Aldicarb LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 0 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldicarb. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. Data Reference: Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1 SWAMP Data: SWAMP Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan). Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: The evaluation guideline for aldicarb is the USEPA Aquatic Life Benchmark of 0.46 ug/L for a fish (chronic). Guideline Reference: OPP Aquatic Life Benchmarks Spatial Representation: The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive). Temporal Representation: The samples were collected between the dates of 2017-06-08 and 2017-06-08 Environmental Conditions: QAPP Information: QAPP for Surface Water Ambient Monitoring Program (SWAMP) QAPP Information Reference(s): SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 157973, Aldicarb	Region 1
Smith River HU, Rowdy Creek

LOE ID: 107369 Pollutant: Aldicarb LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Dissolved Beneficial Use: Municipal & Domestic Supply Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Aldicarb. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: The California Maximum Contaminant Level for aldicarb incorporated by reference in the Water Quality Control Plan, North Coast Basin is 3 ug/L. Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: Guideline Reference: Spatial Representation: The samples were collected at 1 monitoring site(s) (103RW0319) Temporal Representation: The samples were collected between the dates of 2015-06-23 and 2015-06-23 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157973, Aldicarb	Region 1
Smith River HU, Rowdy Creek

LOE ID: 113816 Pollutant: Aldicarb LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Municipal & Domestic Supply Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Aldicarb. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: The California Maximum Contaminant Level for aldicarb incorporated by reference in the Water Quality Control Plan, North Coast Basin is 3 ug/L. Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: Guideline Reference: Spatial Representation:

DECISION ID

157854

Region 1

Smith River HU, Rowdy Creek

Pollutant:	Atrazine
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157854, Atrazine	Region 1
Smith River HU, Rowdy Creek

LOE ID:

102289

Pollutant:

Atrazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The maximum contaminant level listed in Table 64431-A for atrazine is 1 ug/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2013-11-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157854, Atrazine	Region 1
Smith River HU, Rowdy Creek

LOE ID:

102285

Pollutant:

Atrazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The maximum contaminant level listed in Table 64431-A for atrazine is 1 ug/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0129)

Temporal Representation:

The samples were collected between the dates of 2013-08-07 and 2013-08-07

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157854, Atrazine	Region 1
Smith River HU, Rowdy Creek

LOE ID:

110885

Pollutant:

Atrazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

The samples were collected at 1 monitoring site(s) (103RW0129)

Temporal Representation:

The samples were collected between the dates of 2013-08-07 and 2013-08-07

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157973, Aldicarb	Region 1
Smith River HU, Rowdy Creek

LOE ID:

104216

Pollutant:

Aldicarb

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for aldicarb incorporated by reference in the Water Quality Control Plan, North Coast Basin is 3 ug/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2015-03-23 and 2015-03-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157973, Aldicarb	Region 1
Smith River HU, Rowdy Creek

LOE ID:

115107

Pollutant:

Aldicarb

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for aldicarb incorporated by reference in the Water Quality Control Plan, North Coast Basin is 3 ug/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157973, Aldicarb	Region 1
Smith River HU, Rowdy Creek

LOE ID:

113823

Pollutant:

Aldicarb

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for aldicarb incorporated by reference in the Water Quality Control Plan, North Coast Basin is 3 ug/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2013-10-01 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

2ellspacing="0" cellpadding="0">

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for Atrazine is the USEPA Aquatic Life Benchmark of < 1 ug/L for a nonvascular plant (acute). The benchmark was derived from a \less-than\" value (for example, <1,500) and may underestimate toxicity."

Guideline Reference:

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2015-03-11 and 2015-03-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 157854, Atrazine	Region 1
Smith River HU, Rowdy Creek

LOE ID:

102287

Pollutant:

Atrazine

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2013-11-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 157854, Atrazine	Region 1
Smith River HU, Rowdy Creek

LOE ID:

114606

Pollutant:

Atrazine

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2013-10-01 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 157854, Atrazine	Region 1
Smith River HU, Rowdy Creek

LOE ID:

102284

Pollutant:

Atrazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Line of Evidence (LOE) for Decision ID 157973, Aldicarb

Region 1

Smith River HU, Rowdy Creek

LOE ID:

102707

Pollutant:

Aldicarb

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for aldicarb incorporated by reference in the Water Quality Control Plan, North Coast Basin is 3 ug/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2015-03-23 and 2015-03-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157973, Aldicarb	Region 1
Smith River HU, Rowdy Creek

LOE ID:

348955

Pollutant:

Aldicarb

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for aldicarb is the USEPA Aquatic Life Benchmark of 0.46 ug/L for a fish (chronic).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW0129 (Rowdy Creek above Smith River).

Temporal Representation:

The samples were collected between the dates of 2013-08-07 and 2013-08-07

Environmental Conditions:

QAPP Information:

Generic SWAMP QAPrP

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

Line of Evidence (LOE) for Decision ID 157973, Aldicarb	Region 1
Smith River HU, Rowdy Creek

LOE ID:

348967

Pollutant:

Aldicarb

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for aldicarb is the USEPA Aquatic Life Benchmark of 0.46 ug/L for a fish (chronic).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW0319 (Rowdy Creek at Alexander Access).

Temporal Representation:

The samples were collected between the dates of 2015-03-11 and 2015-03-23

Environmental Conditions:

QAPP Information:

Generic SWAMP QAPrP

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

Line of Evidence (LOE) for Decision ID 157973, Aldicarb

Region 1

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0129)

Temporal Representation:

The samples were collected between the dates of 2013-08-07 and 2013-08-07

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 157854, Atrazine	Region 1
Smith River HU, Rowdy Creek

LOE ID:

110889

Pollutant:

Atrazine

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2015-03-12 and 2015-03-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 157854, Atrazine	Region 1
Smith River HU, Rowdy Creek

LOE ID:

110879

Pollutant:

Atrazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The maximum contaminant level listed in Table 64431-A for atrazine is 1 ug/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157854, Atrazine	Region 1
Smith River HU, Rowdy Creek

LOE ID:

110881

Pollutant:

Atrazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Smith River HU, Rowdy Creek

LOE ID:

348947

Pollutant:

Aldicarb

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for aldicarb is the USEPA Aquatic Life Benchmark of 0.46 ug/L for a fish (chronic).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Generic SWAMP QAPrP

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

Line of Evidence (LOE) for Decision ID 157973, Aldicarb	Region 1
Smith River HU, Rowdy Creek

LOE ID:

348981

Pollutant:

Aldicarb

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for aldicarb is the USEPA Aquatic Life Benchmark of 0.46 ug/L for a fish (chronic).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2015-03-12 and 2015-03-23

Environmental Conditions:

QAPP Information:

Generic SWAMP QAPrP

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

Line of Evidence (LOE) for Decision ID 157973, Aldicarb	Region 1
Smith River HU, Rowdy Creek

LOE ID:

348983

Pollutant:

Aldicarb

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for aldicarb is the USEPA Aquatic Life Benchmark of 0.46 ug/L for a fish (chronic).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2013-10-01 and 2013-11-05

Environmental Conditions:

QAPP Information:

Generic SWAMP QAPrP

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

Line of Evidence (LOE) for Decision ID 157973, Aldicarb	Region 1
Smith River HU, Rowdy Creek

LOE ID:

348976

Pollutant:

Aldicarb

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for aldicarb is the USEPA Aquatic Life Benchmark of 0.46 ug/L for a fish (chronic).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW0319 (Rowdy Creek at Alexander Access).

Temporal Representation:

The samples were collected between the dates of 2013-11-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Generic SWAMP QAPrP

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

Line of Evidence (LOE) for Decision ID 157973, Aldicarb	Region 1
Smith River HU, Rowdy Creek

LOE ID:

348965

Pollutant:

Aldicarb

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for aldicarb is the USEPA Aquatic Life Benchmark of 0.46 ug/L for a fish (chronic).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW0319 (Rowdy Creek at Alexander Access).

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Generic SWAMP QAPrP

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

ign="left" valign="top" width="67%">Dissolved Beneficial Use: Municipal & Domestic Supply Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Atrazine. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The maximum contaminant level listed in Table 64431-A for atrazine is 1 ug/L. Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: Guideline Reference: Spatial Representation: The samples were collected at 1 monitoring site(s) (103RW1599) Temporal Representation: The samples were collected between the dates of 2015-06-23 and 2015-06-23 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157854, Atrazine	Region 1
Smith River HU, Rowdy Creek

LOE ID: 110880 Pollutant: Atrazine LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Dissolved Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Atrazine. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan). Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: The evaluation guideline for Atrazine is the USEPA Aquatic Life Benchmark of < 1 ug/L for a nonvascular plant (acute). The benchmark was derived from a \less-than\" value (for example, <1,500) and may underestimate toxicity." Guideline Reference: OPP Aquatic Life Benchmarks Spatial Representation: The samples were collected at 1 monitoring site(s) (103RW1599) Temporal Representation: The samples were collected between the dates of 2015-06-23 and 2015-06-23 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157854, Atrazine	Region 1
Smith River HU, Rowdy Creek

LOE ID: 110878 Pollutant: Atrazine LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Dissolved Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Atrazine. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan). Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: The evaluation guideline for Atrazine is the USEPA Aquatic Life Benchmark of < 1 ug/L for a nonvascular plant (acute). The benchmark was derived from a \less-than\" value (for example, <1,500) and may underestimate toxicity." Guideline Reference: OPP Aquatic Life Benchmarks Spatial Representation: The samples were collected at 1 monitoring site(s) (103RW0319) Temporal Representation: The samples were collected between the dates of 2015-06-23 and 2015-06-23 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157854, Atrazine	Region 1
Smith River HU, Rowdy Creek

LOE ID: 323731 Pollutant: Atrazine LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Atrazine. Data Reference: Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1 SWAMP Data: SWAMP Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan). Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: The evaluation guideline for Atrazine is the USEPA Aquatic Life Benchmark of < 1 ug/L for a nonvascular plant (acute). The benchmark was derived from a 'less-than' value (for example, <1,500) and may underestimate toxicity. Guideline Reference: OPP Aquatic Life Benchmarks Spatial Representation: The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive). Temporal Representation: The samples were collected between the dates of 2017-06-08 and 2017-06-08 Environmental Conditions: QAPP Information: QAPP for Surface Water Ambient Monitoring Program (SWAMP) QAPP Information Reference(s): SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 157854, Atrazine	Region 1
Smith River HU, Rowdy Creek

LOE ID: 114608 Pollutant: Atrazine LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Municipal & Domestic Supply Number of Samples: 2 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Atrazine. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The maximum contaminant level listed in Table 64431-A for atrazine is 1 ug/L. Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: Guideline Reference:

DECISION ID

157975

Region 1

Smith River HU, Rowdy Creek

Pollutant:	Aldrin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID:

108660

Pollutant:

Aldrin

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Standards 2000. Establishment of numeric crd align="left" valign="top" width="33%">Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2013-10-01 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157854, Atrazine	Region 1
Smith River HU, Rowdy Creek

LOE ID:

110891

Pollutant:

Atrazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The maximum contaminant level listed in Table 64431-A for atrazine is 1 ug/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2015-03-12 and 2015-03-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157854, Atrazine	Region 1
Smith River HU, Rowdy Creek

LOE ID:

110887

Pollutant:

Atrazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The maximum contaminant level listed in Table 64431-A for atrazine is 1 ug/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2015-03-11 and 2015-03-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157854, Atrazine	Region 1
Smith River HU, Rowdy Creek

LOE ID:

323715

Pollutant:

Atrazine

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 from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The maximum contaminant level listed in Table 64431-A for atrazine is 1 ug/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

iteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency Evaluation Guideline: Guideline Reference: Spatial Representation: Data was collected from 1 station(s) (Station Code(s) 103RW0319). Temporal Representation: Date for this waterbody was collected over the date range 2013-11-05 to 2013-11-05 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID: 115073 Pollutant: Aldrin LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms Number of Samples: 0 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. The established numeric criteria for aldrin criteria for the protection of human health from consumption of organisms only is 0.00014 ug/L (California Toxics Rule, 2000). Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency Evaluation Guideline: Guideline Reference: Spatial Representation: Data was collected from 1 station(s) (Station Code(s) 103RW0319). Temporal Representation: Date for this waterbody was collected over the date range 2015-06-23 to 2015-06-23 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID: 322877 Pollutant: Aldrin LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Aldrin. Data Reference: Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1 SWAMP Data: SWAMP Water Quality Objective/Criterion: The aldrin criterion maximum concentration (expressed as a 1-day average) to protect aquatic life in freshwater is 1.5 ug/L. The criterion of 3 ug/L provided in the California Toxics Rule is an instantaneous maximum concentration and was divided by 2 in order to better represent a criterion maximum concentration (CMC) value as specified in footnote (g) of Table (b)(1) of the California Toxics Rule (2000). Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency Evaluation Guideline: Guideline Reference: Spatial Representation: The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive). Temporal Representation: The samples were collected between the dates of 2017-06-08 and 2017-06-08 Environmental Conditions: QAPP Information: QAPP for Surface Water Ambient Monitoring Program (SWAMP) QAPP Information Reference(s): SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID: 322872 Pollutant: Aldrin LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Municipal & Domestic Supply Number of Samples: 0 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. Data Reference: Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1 SWAMP Data: SWAMP

DECISION ID

157893

Region 1

Smith River HU, Rowdy Creek

Pollutant:	Azinphos-methyl (Guthion)
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157893, Azinphos-methyl (Guthion)	Region 1
Smith River HU, Rowdy Creek

LOE ID:

323738

Pollutant:

Azinphos-methyl (Guthion)

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 SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Azinphos Methyl. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

T">Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. The established numeric criterion for aldrin to protect of human health from the consumption of water and organisms is 0.00013 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID:

108915

Pollutant:

Aldrin

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. The established numeric criteria for aldrin to protect aquatic life in freshwater as criterion maximum concentration is 3 ug/L . This established criteria was divided by 2 in order to better represent a CMC value as specified in footnote g of Table (b)(1) of the California Toxics Rule, 2000.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2013-10-01 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

Line of Evidence (LOE) for Decision ID 157893, Azinphos-methyl (Guthion)	Region 1
Smith River HU, Rowdy Creek

LOE ID:

108824

Pollutant:

Azinphos-methyl (Guthion)

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 SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Azinphos Methyl. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The National Recommended Water Quality Criteria for Azinphos Methyl (Guthion) for the protection of freshwater aquatic life is a maximum of 0.01 ug/l.

Guideline Reference:

Spatial Representation:

Data was collected from 1 station(s) (Station Code(s) 103RW0319).

Temporal Representation:

Date for this waterbody was collected over the date range 2015-03-11 to 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157893, Azinphos-methyl (Guthion)	Region 1
Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID:

108684

Pollutant:

Aldrin

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. The established numeric criteria for aldrin to protect aquatic life in freshwater as criterion maximum concentration is 3 ug/L . This established criteria was divided by 2 in order to better represent a CMC value as specified in footnote g of Table (b)(1) of the California Toxics Rule, 2000.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID:

105825

Pollutant:

Aldrin

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:

Water Quality Assessment Data for the 201olspan="2">

Smith River HU, Rowdy Creek

LOE ID:

114047

Pollutant:

Azinphos-methyl (Guthion)

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 SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Azinphos Methyl. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The National Recommended Water Quality Criteria for Azinphos Methyl (Guthion) for the protection of freshwater aquatic life is a maximum of 0.01 ug/l.

Guideline Reference:

Spatial Representation:

Data was collected from 1 station(s) (Station Code(s) 103RW1599).

Temporal Representation:

Date for this waterbody was collected over the date range 2015-03-12 to 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157893, Azinphos-methyl (Guthion)	Region 1
Smith River HU, Rowdy Creek

LOE ID:

115785

Pollutant:

Azinphos-methyl (Guthion)

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 SWAMP RWB1 Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Azinphos Methyl. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The National Recommended Water Quality Criteria for Azinphos Methyl (Guthion) for the protection of freshwater aquatic life is a maximum of 0.01 ug/l.

Guideline Reference:

Spatial Representation:

Data was collected from 1 station(s) (Station Code(s) 103RW0319).

Temporal Representation:

Date for this waterbody was collected over the date range 2013-11-05 to 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157893, Azinphos-methyl (Guthion)	Region 1
Smith River HU, Rowdy Creek

LOE ID:

115789

Pollutant:

Azinphos-methyl (Guthion)

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 SWAMP RWB1 Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Azinphos Methyl. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The National Recommended Water Quality Criteria for Azinphos Methyl (Guthion) for the protection of freshwater aquatic life is a maximum of 0.01 ug/l.

Guideline Reference:

Spatial Representation:

Data was collected from 1 station(s) (Station Code(s) 103RW1599).

Temporal Representation:

Date for this waterbody was collected over the date range 2013-10-01 to 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157893, Azinphos-methyl (Guthion)	Region 1
Smith River HU, Rowdy Creek

LOE ID:

115781

Pollutant:

Azinphos-methyl (Guthion)

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 SWAMP RWB1 Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Azinphos Methyl. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The National Recommended Water Quality Criteria for Azinphos Methyl (Guthion) for the protection of freshwater aquatic life is a maximum of 0.01 ug/l.

Guideline Reference:

Spatial Representation:

Data was collected from 1 station(s) (Station Code(s) 103RW0129).

Temporal Representation:

Date for this waterbody was collected over the date range 2013-08-07 to 2013-08-07

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

8 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. The established numeric criteria for aldrin to protect aquatic life in freshwater as criterion maximum concentration is 3 ug/L . This established criteria was divided by 2 in order to better represent a CMC value as specified in footnote g of Table (b)(1) of the California Toxics Rule, 2000. Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency Evaluation Guideline: Guideline Reference: Spatial Representation: The samples were collected at 1 monitoring site(s) (103RW0319) Temporal Representation: The samples were collected between the dates of 2013-11-05 and 2013-11-05 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID: 104220 Pollutant: Aldrin LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Aldrin. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. The established numeric criteria for aldrin to protect aquatic life in freshwater as criterion maximum concentration is 3 ug/L . This established criteria was divided by 2 in order to better represent a CMC value as specified in footnote g of Table (b)(1) of the California Toxics Rule, 2000. Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency Evaluation Guideline: Guideline Reference: Spatial Representation: The samples were collected at 1 monitoring site(s) (103RW0319) Temporal Representation: The samples were collected between the dates of 2015-06-23 and 2015-06-23 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID: 113824 Pollutant: Aldrin LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Aldrin. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. The established numeric criteria for aldrin to protect aquatic life in freshwater as criterion maximum concentration is 3 ug/L . This established criteria was divided by 2 in order to better represent a CMC value as specified in footnote g of Table (b)(1) of the California Toxics Rule, 2000. Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency Evaluation Guideline: Guideline Reference: Spatial Representation: The samples were collected at 1 monitoring site(s) (103RW0129) Temporal Representation: The samples were collected between the dates of 2013-08-07 and 2013-08-07 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID: 322867 Pollutant: Aldrin LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms Number of Samples: 0 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING

DECISION ID

101716

Region 1

Smith River HU, Rowdy Creek

Pollutant:	Azoxystrobin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line(s) of evidence are necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of the samples exceeded the objective and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

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

Listing Extent:

Line of Evidence (LOE) for Decision ID 101716, Azoxystrobin	Region 1
Smith River HU, Rowdy Creek

LOE ID:

111028

Pollutant:

Azoxystrobin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for Azoxystrobin is the USEPA Aquatic Life Benchmark of 44 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 101716, Azoxystrobin	Region 1
Smith River HU, Rowdy Creek

LOE ID:

110893

Pollutant:

Azoxystrobin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for Azoxystrobin is the USEPA Aquatic Life Benchmark of 44 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

lign="top" width="33%">Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. Data Reference: Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1 SWAMP Data: SWAMP Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. The established numeric criterion for aldrin criteria for the protection of human health from consumption of organisms only is 0.00014 ug/L (California Toxics Rule, 2000). Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency Evaluation Guideline: Guideline Reference: Spatial Representation: The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive). Temporal Representation: The samples were collected between the dates of 2017-06-08 and 2017-06-08 Environmental Conditions: QAPP Information: QAPP for Surface Water Ambient Monitoring Program (SWAMP) QAPP Information Reference(s): SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID: 108659 Pollutant: Aldrin LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Municipal & Domestic Supply Number of Samples: 0 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. The established numeric criteria for aldrin to protect of human health from the consumption of water and organisms is 0.00013 ug/L (California Toxics Rule, 2000). Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency Evaluation Guideline: Guideline Reference: <


DECISION ID	104861	Region 1
Smith River HU, Rowdy Creek

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 is being considered for placement on the CWA section 303(d) List under sections 3.9 of the Listing Policy. Under section 3.9, an additional line of evidence associating the Benthic Community Effects with a water or sediment concentration of pollutants is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this indicator. Both CSCI scores and the habitat assessment met the evaluation guideline which indicates beneficial uses are supported. 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 water 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. Both CSCI scores and the habitat assessment met the evaluation guideline which indicates beneficial uses are supported.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

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

Listing Extent:

Objective/Criterion Reference:

Line of Evidence (LOE) for Decision ID 104861, Benthic Community Effects	Region 1
Smith River HU, Rowdy Creek

LOE ID:

96279

Pollutant:

Benthic-Macroinvertebrate Bioassessments

LOE Subgroup:

Population/Community Degradation

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Aquatic Life Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Benthic macroinvertebrate surveys

Data Used to Assess Water Quality:

The site had a CSCI score(s) of 0.99379041. Therefore, this site is not exceeding the water quality objective for the aquatic life beneficial use.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for DFW_ABL_Monitoring.

SWAMP Data:

Water Quality Objective/Criterion:

From the Water Quality Control Plan, North Coast Region: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life.

Spatial Representation:

Data was collected from 1 station(s) (Station Code(s) 103RW0129).

Temporal Representation:

Date for this waterbody was collected over the date range 2013-08-07 to 2013-08-07

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID:

104179

Pollutant:

Aldrin

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 RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 1 station(s) (Station Code(s) 103RW1599).

Temporal Representation:

Date for this waterbody was collected over the date range 2015-06-23 to 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID:

106469

Pollutant:

Aldrin

Water Quality Control Plan (Basin Plan) for the North Coast Region

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 (Rhen, 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.

Guideline Reference:

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

Spatial Representation:

These samples were collected at the following station: 103FC1106

Temporal Representation:

These samples were collected on: 7/15/2014

Environmental Conditions:

QAPP Information:

Data collected following SWAMP QA protocols.

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 104861, Benthic Community Effects	Region 1
Smith River HU, Rowdy Creek

LOE ID:

96285

Pollutant:

Benthic-Macroinvertebrate Bioassessments

LOE Subgroup:

Population/Community Degradation

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Aquatic Life Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Benthic macroinvertebrate surveys

Data Used to Assess Water Quality:

The site had a CSCI score(s) of 0.995365822. Therefore, this site is not exceeding the water quality objective for the aquatic life beneficial use.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Reference Condition Management Plan .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

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

Spatial Representation:

These samples were collected at the following station: 103RDCBCC

Temporal Representation:

These samples were collected on: 7/21/2011

Environmental Conditions:

QAPP Information:

Data collected following SWAMP QA protocols. QAPP for SWAMP Reference Condition Management Plan.

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 104861, Benthic Community Effects	Region 1
Smith River HU, Rowdy Creek

LOE ID:

132795

Pollutant:

Habitat Assessment (Streams)

LOE Subgroup:

Ancillary Line of Evidence

Matrix:

-N/A

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Aquatic Life Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

HABITAT ASSESSMENT

Data Used to Assess Water Quality:

The site had an IPI score of 0.97 which indicates the habitat is Likely Intact.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Reference Condition Management Plan .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Physical characteristics of a site vary due to both natural factors and human disturbance. Statistical models based on a large statewide reference data set can help distinguish natural variability from anthropogenic stress. These models work across the diverse stream types found in California. The Index of Physical Habitat Integrity (IPI) is a multimetric Index developed based on these models to characterize physical habitat condition for streams in California. Index scores near 1 indicate physical habitat conditions similar to reference, whereas lower scores indicate degradation. For the purposes of making statewide assessments, three thresholds (analogous to those used for the CSCI) were established based on the 30th; 10th; and 1st percentiles of IPI scores at reference sites. These three thresholds divide the IPI scoring range into 4 categories of physical condition as follows: greater than or equal to 0.94 = likely intact condition; 0.93 to 0.84 = possibly altered condition; 0.83 to 0.71 = likely altered condition; less than or equal to 0.70 = very likely altered condition. Scores of 0.83 or lower indicate that the physical habitat has been altered and low CSCI scores from this site may be due to impacts to the physical habitat.

Guideline Reference:

An Index to Measure the Quality of Physical Habitat in California Wadeable Streams

Spatial Representation:

These samples were collected at the following station: 103RDCBCC

Temporal Representation:

These samples were collected on: 7/21/2011

Environmental Conditions:

QAPP Information:

Data collected following SWAMP QA protocols. QAPP for SWAMP Reference Condition Management Plan.

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

> LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Municipal & Domestic Supply Number of Samples: 0 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. The established numeric criteria for aldrin to protect of human health from the consumption of water and organisms is 0.00013 ug/L (California Toxics Rule, 2000). Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency Evaluation Guideline: Guideline Reference: Spatial Representation: Data was collected from 1 station(s) (Station Code(s) 103RW1599). Temporal Representation: Date for this waterbody was collected over the date range 2013-10-01 to 2013-11-05 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID: 113789 Pollutant: Aldrin LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms Number of Samples: 0 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: Water Qua


DECISION ID	157856	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Benzene
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157856, Benzene	Region 1
Smith River HU, Rowdy Creek

LOE ID:

323764

Pollutant:

Benzene

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 from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for Benzene incorporated by reference in the Water Quality Control Plan, North Coast Basin is 0.001 mg/L (Water Quality Control Plan, North Coast Basin).

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157856, Benzene	Region 1
Smith River HU, Rowdy Creek

LOE ID:

323761

Pollutant:

Benzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Benzene criterion for the protection of human health from consumption of organisms only is 71 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

lity Control Plan, North Coast Region (NCRWQCB 2018): All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. The established numeric criteria for aldrin criteria for the protection of human health from consumption of organisms only is 0.00014 ug/L (California Toxics Rule, 2000). Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency Evaluation Guideline: Guideline Reference: Spatial Representation: Data was collected from 1 station(s) (Station Code(s) 103RW1599). Temporal Representation: Date for this waterbody was collected over the date range 2013-10-01 to 2013-11-05 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID: 110335 Pollutant: Aldrin LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms Number of Samples: 0 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. The established numeric criteria for aldrin criteria for the protection of human health from consumption of organisms only is 0.00014 ug/L (California Toxics Rule, 2000). Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency Evaluation Guideline: Guideline Reference: Spatial Representation: Data was collected from 1 station(s) (Station Code(s) 103RW1599). Temporal Representation: Date for this waterbody was collected over the date range 2015-06-23 to 2015-06-23 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID: 113787 Pollutant: Aldrin LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms Number of Samples: 0 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. The established numeric criteria for aldrin criteria for the protection of human health from consumption of organisms only is 0.00014 ug/L (California Toxics Rule, 2000). Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency Evaluation Guideline: Guideline Reference: Spatial Representation: Data was collected from 1 station(s) (Station Code(s) 103RW0319). Temporal Representation: Date for this waterbody was collected over the date range 2013-11-05 to 2013-11-05 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID: 113785 Pollutant: Aldrin LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms Number of Samples: 0 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. The established numeric criteria for aldrin criteria for the protection of human health from consumption of organisms only is 0.00014 ug/L (California Toxics Rule, 2000). Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency Evaluation Guideline: Guideline Reference: Spatial Representation: Data was collected from 1 station(s) (Station Code(s) 103RW0129). Temporal Representation: Date for this waterbody was collected over the date range 2013-08-07 to 2013-08-07 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157975, Aldrin	Region 1
Smith River HU, Rowdy Creek

LOE ID: 104176 Pollutant: Aldrin LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Municipal & Domestic Supply Number of Samples: 0 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. The established numeric criteria for aldrin to protect of human health from the consumption of water and organisms is 0.00013 ug/L (California Toxics Rule, 2000). Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency Evaluation Guideline: Guideline Reference: Spatial Representation: Data was collected from 1 station(s) (Station Code(s) 103RW0319). Temporal Representation: Date for this waterbody was collected over the date range 2015-06-23 to 2015-06-23 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	105104	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Benzo(a)anthracene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	"This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line(s) of evidence are necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of the two samples exceeded the objective and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met."

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

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

Listing Extent:

Line of Evidence (LOE) for Decision ID 105104, Benzo(a)anthracene	Region 1
Smith River HU, Rowdy Creek

LOE ID:

121587

Pollutant:

Benzo(a)anthracene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for Benz[a]anthrazene from MacDonald et al., 2000a which states that the probable effect concentration for Benz[a]anthrazene is 1050 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 103RW1599.

Temporal Representation:

Data for this waterbody were collected over the date range 2015-06-23 to 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 105104, Benzo(a)anthracene	Region 1
Smith River HU, Rowdy Creek

LOE ID:

122307

Pollutant:

Benzo(a)anthracene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for Benz[a]anthrazene from MacDonald et al., 2000a which states that the probable effect concentration for Benz[a]anthrazene is 1050 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 103RW0319.

Temporal Representation:

Data for this waterbody were collected over the date range 2015-06-23 to 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	105105	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Benzo(a)pyrene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	"This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line(s) of evidence are necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of the two samples exceeded the objective and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met."

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

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

Listing Extent:

Line of Evidence (LOE) for Decision ID 105105, Benzo(a)pyrene	Region 1
Smith River HU, Rowdy Creek

LOE ID:

121601

Pollutant:

Benzo(a)pyrene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for Benzo[a]pyrene from MacDonald et al., 2000a which states that the probable effect concentration for Benzo[a]pyrene is 1450 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 103RW1599.

Temporal Representation:

Data for this waterbody were collected over the date range 2015-06-23 to 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 105105, Benzo(a)pyrene	Region 1
Smith River HU, Rowdy Creek

LOE ID:

121735

Pollutant:

Benzo(a)pyrene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for Benzo[a]pyrene from MacDonald et al., 2000a which states that the probable effect concentration for Benzo[a]pyrene is 1450 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 103RW0319.

Temporal Representation:

Data for this waterbody were collected over the date range 2015-06-23 to 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	157977	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Alkalinity as CaCO3
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157977, Alkalinity as CaCO3	Region 1
Smith River HU, Rowdy Creek

LOE ID:

102230

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2013-11-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157977, Alkalinity as CaCO3	Region 1
Smith River HU, Rowdy Creek

LOE ID:

115962

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Reference Condition Management Plan .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RDCBCC)

Temporal Representation:

The samples were collected between the dates of 2011-07-21 and 2011-07-21

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157977, Alkalinity as CaCO3	Region 1
Smith River HU, Rowdy Creek

LOE ID:

104243

Pollutant:

Alkalinity as CaCO3

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:


DECISION ID	157949	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Bifenthrin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	LOE 110902 has been replaced by LOE 349100, LOE 120020 has been replaced by LOE 349057, LOE 110896 has been replaced by LOE 349069, and LOE 102305 has been replaced by LOE 349092 due to a reassessment of data using the chronic criterion threshold. 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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157949, Bifenthrin	Region 1
Smith River HU, Rowdy Creek

LOE ID:

349069

Pollutant:

Bifenthrin

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 SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bifenthrin. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan (BasiNumber of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157977, Alkalinity as CaCO3	Region 1
Smith River HU, Rowdy Creek

LOE ID:

102607

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Evaluation Guideline:

The chronic criterion for bifenthrin is 0.1 ng/L (expressed as a 4-day average). If the freely dissolved concentrations of bifenthrin were reported or could be calculated then these values were used for this assessment. In the absence of freely dissolved concentrations, total concentrations were used.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW0319 (Rowdy Creek at Alexander Access).

Temporal Representation:

The samples were collected between the dates of 2015-03-11 and 2015-06-23

Environmental Conditions:

QAPP Information:

Generic SWAMP QAPrP

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

Line of Evidence (LOE) for Decision ID 157949, Bifenthrin	Region 1
Smith River HU, Rowdy Creek

LOE ID:

349084

Pollutant:

Bifenthrin

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 SWAMP RWB1 Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bifenthrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW0129 (Rowdy Creek above Smith River).

Temporal Representation:

The samples were collected between the dates of 2013-08-07 and 2013-08-07

Environmental Conditions:

QAPP Information:

Generic SWAMP QAPrP

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

Line of Evidence (LOE) for Decision ID 157949, Bifenthrin	Region 1
Smith River HU, Rowdy Creek

LOE ID:

349092

Pollutant:

Bifenthrin

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 SWAMP RWB1 Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bifenthrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2013-10-01 and 2013-11-05

Environmental Conditions:

QAPP Information:

Generic SWAMP QAPrP

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157949, Bifenthrin	Region 1
Smith River HU, Rowdy Creek

LOE ID:

323801

Pollutant:

Bifenthrin

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 SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bifenthrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Line of Evidence (LOE) for Decision ID 157977, Alkalinity as CaCO3	Region 1
Smith River HU, Rowdy Creek

LOE ID:

102232

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2013-10-01 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157977, Alkalinity as CaCO3	Region 1
Smith River HU, Rowdy Creek

LOE ID:

102228

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0129)

Temporal Representation:

The samples were collected between the dates of 2013-08-07 and 2013-08-07

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157977, Alkalinity as CaCO3	Region 1
Smith River HU, Rowdy Creek

LOE ID:

322998

Pollutant:

Alkalinity as CaCO3

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:

Benthic, Field, Habitat, Tissue, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

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: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2020-01-25 and 2021-10-25

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Water Quality Control Plan (Basin Plan) for the North Coast Region

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

Line of Evidence (LOE) for Decision ID 157949, Bifenthrin	Region 1
Smith River HU, Rowdy Creek

LOE ID:

121752

Pollutant:

Bifenthrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan for the North Coast Region)

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for bifenthrin is the median lethal concentration (LC50) of 0.43 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.43 ug/g is the geometric mean of LC50 values for bifenthrin from Amweg et al. (2005) and Amweg and Weston (2007).

Guideline Reference:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Guideline Reference:

Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 103RW0319.

Temporal Representation:

Data for this waterbody were collected over the date range 2015-06-23 to 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157949, Bifenthrin	Region 1
Smith River HU, Rowdy Creek

LOE ID:

349057

Pollutant:

Bifenthrin

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 SWAMP RWB1 Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bifenthrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW0319 (Rowdy Creek at Alexander Access).

Temporal Representation:

The samples were collected between the dates of 2013-11-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Generic SWAMP QAPrP

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

Line of Evidence (LOE) for Decision ID 157949, Bifenthrin	Region 1
Smith River HU, Rowdy Creek

LOE ID:

349100

Pollutant:

Bifenthrin

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 SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bifenthrin. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2015-03-12 and 2015-06-23

Environmental Conditions:

QAPP Information:

Generic SWAMP QAPrP

QAPP Information Reference(s):

Benthic, Field, Habitat, Tissue, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

="75%">

Line of Evidence (LOE) for Decision ID 157977, Alkalinity as CaCO3

Region 1

Smith River HU, Rowdy Creek

LOE ID:

323092

Pollutant:

Alkalinity as CaCO3

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

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: 103RW2000 (Rowdy Creek at Highway 101).

Temporal Representation:

The samples were collected between the dates of 2020-01-25 and 2021-10-25

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

Line of Evidence (LOE) for Decision ID 157977, Alkalinity as CaCO3	Region 1
Smith River HU, Rowdy Creek

LOE ID:

104247

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2015-03-23 and 2015-03-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157977, Alkalinity as CaCO3	Region 1
Smith River HU, Rowdy Creek

LOE ID:

112293

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Reference Condition Management Plan .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RDCBCC)

Temporal Representation:

The samples were collected between the dates of 2011-07-21 and 2011-07-21

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157977, Alkalinity as CaCO3	Region 1
Smith River HU, Rowdy Creek

LOE ID:

104246

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2015-03-23 and 2015-03-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	102997	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Boscalid
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line(s) of evidence are necessary to assess listing status.Two lines of evidence are available in the administrative record to assess this pollutant. None samples exceed the objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of the samples exceeded the objective and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

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

Listing Extent:

Line of Evidence (LOE) for Decision ID 102997, Boscalid	Region 1
Smith River HU, Rowdy Creek

LOE ID:

110910

Pollutant:

Boscalid

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for Boscalid is the USEPA Aquatic Life Benchmark of 116 ug/L for a fish (chronic).

Guideline Reference:

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 102997, Boscalid	Region 1
Smith River HU, Rowdy Creek

LOE ID:

110909

Pollutant:

Boscalid

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for Boscalid is the USEPA Aquatic Life Benchmark of 116 ug/L for a fish (chronic).

Guideline Reference:

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):


DECISION ID	157848	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Allethrin
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157848, Allethrin	Region 1
Smith River HU, Rowdy Creek

LOE ID:

323152

Pollutant:

Allethrin

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 from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for Allethrin is the USEPA Aquatic Life Benchmark of 1.05 ug/L for an invertebrate (acute).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157938	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Bromacil
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157938, Bromacil	Region 1
Smith River HU, Rowdy Creek

LOE ID:

323817

Pollutant:

Bromacil

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA Health Advisory for lifetime exposure to Bromacil as a drinking water level is a concentration of 0.07 mg/L

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157938, Bromacil	Region 1
Smith River HU, Rowdy Creek

LOE ID:

323815

Pollutant:

Bromacil

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for Bromacil is the USEPA Aquatic Life Benchmark of 6.8 ug/L for a nonvascular plant (acute).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157967	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Bromobenzene
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157967, Bromobenzene	Region 1
Smith River HU, Rowdy Creek

LOE ID:

323821

Pollutant:

Bromobenzene

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

USEPA's Drinking Water Health AdvisoryNAexposure limit for life-time exposure to Bromobenzen is a concentration of 0.06 mg/L

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1


DECISION ID	157968	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Bromochloromethane
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157968, Bromochloromethane	Region 1
Smith River HU, Rowdy Creek

LOE ID:

323825

Pollutant:

Bromochloromethane

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

USEPA's Drinking Water Health advisory for life-time exposure to Bromochloromethane is a concentration of 0.09 mg/L

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .


DECISION ID	102624	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Aluminum
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3 of the Listing Policy. Under section 3 a single line of evidence are necessary to assess listing status. Five lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of the samples exceeded the objective and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

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

Listing Extent:

Line of Evidence (LOE) for Decision ID 102624, Aluminum	Region 1
Smith River HU, Rowdy Creek

LOE ID:

104251

Pollutant:

Aluminum

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 102624, Aluminum	Region 1
Smith River HU, Rowdy Creek

LOE ID:

104252

Pollutant:

Aluminum

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 102624, Aluminum	Region 1
Smith River HU, Rowdy Creek

DECISION ID

157858

Region 1

Smith River HU, Rowdy Creek

Pollutant:	Bromoform
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157858, Bromoform	Region 1
Smith River HU, Rowdy Creek

LOE ID:

323835

Pollutant:

Bromoform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

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 from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The bromoform criterion for the protection of human health from consumption of organisms only is 360 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157858, Bromoform	Region 1
Smith River HU, Rowdy Creek

LOE ID:

323833

Pollutant:

Bromoform

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The bromoform criterion for the protection of human health from the consumption of water and organisms is 4.3 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

="top" width="33%">LOE ID: 115143 Pollutant: Aluminum LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Dissolved Beneficial Use: Municipal & Domestic Supply Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Aluminum. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The secondary maximum contaminant level listed in Table 64449-A for Aluminum is 0.2 mg/L. Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: Guideline Reference: Spatial Representation: The samples were collected at 1 monitoring site(s) (103RW0319) Temporal Representation: The samples were collected between the dates of 2015-06-23 and 2015-06-23 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 102624, Aluminum	Region 1
Smith River HU, Rowdy Creek

LOE ID: 104249 Pollutant: Aluminum LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Dissolved Beneficial Use: Municipal & Domestic Supply Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Aluminum. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The secondary maximum contaminant level listed in Table 64449-A for Aluminum is 0.2 mg/L. Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: Guideline Reference: Spatial Representation: The samples were collected at 1 monitoring site(s) (103RW1599) Temporal Representation: The samples were collected between the dates of 2015-06-23 and 2015-06-23 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 102624, Aluminum	Region 1
Smith River HU, Rowdy Creek

LOE ID: 103515 Pollutant: Aluminum LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Municipal & Domestic Supply Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP Reference Condition Management Plan data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Aluminum. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Reference Condition Management Plan . SWAMP Data: SWAMP Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The secondary maximum contaminant level listed in Table 64449-A for Aluminum is 0.2 mg/L. Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: Guideline Reference: Spatial Representation: The samples were collected at 1 monitoring site(s) (103RDCBCC) Temporal Representation: The samples were collected between the dates of 2011-07-21 and 2011-07-21 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	101847	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Cadmium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line(s) of evidence are necessary to assess listing status. Nine lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of the samples exceeded the objective and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

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

Listing Extent:

Line of Evidence (LOE) for Decision ID 101847, Cadmium	Region 1
Smith River HU, Rowdy Creek

LOE ID:

110918

Pollutant:

Cadmium

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sa


DECISION ID	157980	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Ametryn
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157980, Ametryn	Region 1
Smith River HU, Rowdy Creek

LOE ID:

101839

Pollutant:

Ametryn

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA Health Advisory for lifetime exposure to Ametryn as a drinking water level is a concentration of 0.06 mg/L

Guideline Reference:

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 101847, Cadmium	Region 1
Smith River HU, Rowdy Creek

LOE ID:

110914

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 101847, Cadmium

Region 1

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2013-11-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157980, Ametryn	Region 1
Smith River HU, Rowdy Creek

LOE ID:

101837

Pollutant:

Ametryn

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA Health Advisory for lifetime exposure to Ametryn as a drinking water level is a concentration of 0.06 mg/L

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0129)

Temporal Representation:

The samples were collected between the dates of 2013-08-07 and 2013-08-07

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157980, Ametryn	Region 1
Smith River HU, Rowdy Creek

LOE ID:

323265

Pollutant:

Ametryn

LOE Subgroup:

Pollutant-Water

Matrix:

Smith River HU, Rowdy Creek

LOE ID:

110922

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The maximum contaminant level listed in Table 64431-A for cadmium 0.005 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 101847, Cadmium	Region 1
Smith River HU, Rowdy Creek

LOE ID:

115670

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Reference Condition Management Plan .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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 from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for ametryn is the USEPA Aquatic Life Benchmark of 3.67 ug/L for nonvascular plants.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157980, Ametryn	Region 1
Smith River HU, Rowdy Creek

LOE ID:

323259

Pollutant:

Ametryn

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA Health Advisory for lifetime exposure to ametryn as a drinking water level is a concentration of 0.06 mg/L

Guideline Reference:

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RDCBCC)

Temporal Representation:

The samples were collected between the dates of 2011-07-21 and 2011-07-21

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 101847, Cadmium	Region 1
Smith River HU, Rowdy Creek

LOE ID:

108164

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Reference Condition Management Plan .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The maximum contaminant level listed in Table 64431-A for cadmium 0.005 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RDCBCC)

Temporal Representation:

The samples were collected between the dates of 2011-07-21 and 2011-07-21

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 101847, Cadmium	Region 1
Smith River HU, Rowdy Creek

LOE ID:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

Line of Evidence (LOE) for Decision ID 157980, Ametryn	Region 1
Smith River HU, Rowdy Creek

LOE ID:

112516

Pollutant:

Ametryn

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA Health Advisory for lifetime exposure to Ametryn as a drinking water level is a concentration of 0.06 mg/L

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157980, Ametryn	Region 1
Smith River HU, Rowdy Creek

LOE ID:

104255

Pollutant:

Ametryn

LOE Subgroup:

Pollutant-Water

Matrix:

Water

121704

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

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 SWAMP RWB1 Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Cadmium .

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for cadmium in 4.98 mg/Kg dry weight (MacDonald et al. 2000a)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 103RW0319.

Temporal Representation:

Data for this waterbody were collected over the date range 2013-11-05 to 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 101847, Cadmium	Region 1
Smith River HU, Rowdy Creek

LOE ID:

110923

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The maximum contaminant level listed in Table 64431-A for cadmium 0.005 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 101847, Cadmium	Region 1
Smith River HU, Rowdy Creek

LOE ID:

122211

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for cadmium in 4.98 mg/Kg dry weight (MacDonald et al. 2000a)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 103RW1599.

Temporal Representation:

Data for this waterbody were collected over the date range 2015-06-23 to 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 101847, Cadmium	Region 1
Smith River HU, Rowdy Creek

LOE ID:

121913

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for cadmium in 4.98 mg/Kg dry weight (MacDonald et al. 2000a)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 103RW0319.

Temporal Representation:

Data for this waterbody were collected over the date range 2015-06-23 to 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

eft" valign="top" width="33%">Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA Health Advisory for lifetime exposure to Ametryn as a drinking water level is a concentration of 0.06 mg/L

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157980, Ametryn	Region 1
Smith River HU, Rowdy Creek

LOE ID:

101842

Pollutant:

Ametryn

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA Health Advisory for lifetime exposure to Ametryn as a drinking water level is a concentration of 0.06 mg/L

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2013-10-01 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157980, Ametryn	Region 1
Smith River HU, Rowdy Creek

LOE ID:

118951

Pollutant:

Ametryn

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA Health Advisory for lifetime exposure to Ametryn as a drinking water level is a concentration of 0.06 mg/L

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2015-03-11 and 2015-03-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157980, Ametryn	Region 1
Smith River HU, Rowdy Creek

LOE ID:

115154

Pollutant:

Ametryn

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA Health Advisory for lifetime exposure to Ametryn as a drinking water level is a concentration of 0.06 mg/L

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2015-03-12 and 2015-03-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	157859	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Carbaryl
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157859, Carbaryl	Region 1
Smith River HU, Rowdy Creek

LOE ID:

110924

Pollutant:

Carbaryl

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA national ambient water quality criterion for freshwater aquatic life criterion continuous concentration expressed as a 4 day average for carbaryl is 2.1 µg/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157859, Carbaryl	Region 1
Smith River HU, Rowdy Creek

LOE ID:

102766

Pollutant:

Carbaryl

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (Water Quality Control Plan, North Coast Basin).

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA Health Advisory for carbaryl as a drinking water level with a one in a million cancer risk is 0.04 mg/L.

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157859, Carbaryl	Region 1
Smith River HU, Rowdy Creek

LOE ID:

110927

Pollutant:

Carbaryl

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (Water Quality Control Plan, North Coast Basin).

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA Health Advisory for carbaryl as a drinking water level with a one in a million cancer risk is 0.04 mg/L.

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157859, Carbaryl	Region 1
Smith River HU, Rowdy Creek

LOE ID:

102772

Pollutant:

Carbaryl

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA national ambient water quality criterion fo


DECISION ID	104124	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Aminomethyl Phosphonic Acid (AMPA)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line(s) of evidence are necessary to assess listing status. Five line(s) of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None samples exceeded the objective and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

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

Listing Extent:

Line of Evidence (LOE) for Decision ID 104124, Aminomethyl Phosphonic Acid (AMPA)	Region 1
Smith River HU, Rowdy Creek

LOE ID:

107300

Pollutant:

Aminomethyl Phosphonic Acid (AMPA)

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for AMPA is the USEPA Aquatic Life Benchmark of 249500 ug/L for a fish (acute).

Guideline Reference:

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2015-03-11 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104124, Aminomethyl Phosphonic Acid (AMPA)	Region 1
Smith River HU, Rowdy Creek

LOE ID:

113308

Pollutant:

Aminomethyl Phosphonic Acid (AMPA)

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for AMPA is the USEPA Aquatic Life Benchmark of 249500 ug/L for a fish (acute).

Guideline Reference:

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2013-11-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104124, Aminomethyl Phosphonic Acid (AMPA)

Region 1 &r freshwater aquatic life criterion continuous concentration expressed as a 4 day average for carbaryl is 2.1 µg/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2015-03-23 and 2015-03-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157859, Carbaryl	Region 1
Smith River HU, Rowdy Creek

LOE ID:

115101

Pollutant:

Carbaryl

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA national ambient water quality criterion for freshwater aquatic life criterion continuous concentration expressed as a 4 day average for carbaryl is 2.1 µg/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157859, Carbaryl	Region 1
Smith River HU, Rowdy Creek
Smith River HU, Rowdy Creek

LOE ID:

114579

Pollutant:

Aminomethyl Phosphonic Acid (AMPA)

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for AMPA is the USEPA Aquatic Life Benchmark of 249500 ug/L for a fish (acute).

Guideline Reference:

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2013-10-01 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104124, Aminomethyl Phosphonic Acid (AMPA)	Region 1
Smith River HU, Rowdy Creek

LOE ID:

102261

Pollutant:

Aminomethyl Phosphonic Acid (AMPA)

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for AMPA is the USEPA Aquatic Life Benchmark of 249500 ug/L for a fish (acute).

Guideline Reference:

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0129)

Temporal Representation:

The samples were collected between the dates of 2013-08-07 and 2013-08-07

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 104124, Aminomethyl Phosphonic Acid (AMPA)	Region 1
Smith River HU, Rowdy Creek

LOE ID:

114354

Pollutant:

Aminomethyl Phosphonic Acid (AMPA)

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for AMPA is the USEPA Aquatic Life Benchmark of 249500 ug/L for a fish (acute).

Guideline Reference:

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2015-03-12 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

able>

LOE ID:

323935

Pollutant:

Carbaryl

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 from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (Water Quality Control Plan, North Coast Basin).

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA Health Advisory for carbaryl as a drinking water level with a one in a million cancer risk is 0.04 mg/L.

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

Line of Evidence (LOE) for Decision ID 157859, Carbaryl	Region 1
Smith River HU, Rowdy Creek

LOE ID:

323937

Pollutant:

Carbaryl

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA national ambient water quality criterion for freshwater aquatic life criterion continuous concentration expressed as a 4 day average for carbaryl is 2.1 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

Line of Evidence (LOE) for Decision ID 157859, Carbaryl	Region 1
Smith River HU, Rowdy Creek

LOE ID:

115741

Pollutant:

Carbaryl

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:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (Water Quality Control Plan, North Coast Basin).

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA Health Advisory for carbaryl as a drinking water level with a one in a million cancer risk is 0.04 mg/L.

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2013-10-01 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157859, Carbaryl	Region 1
Smith River HU, Rowdy Creek

DECISION ID

104753

Region 1

Smith River HU, Rowdy Creek

Pollutant:	Ammonia
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Ten lines of evidence are available in the administrative record to assess this pollutant. Zero of seven samples exceed the objective for COLD and zero of 11 samples exceed the objective for MUN. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of seven samples exceed the objective for COLD and zero of 11 samples exceed the objective for MUN. This sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

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

Listing Extent:

Line of Evidence (LOE) for Decision ID 104753, Ammonia	Region 1
Smith River HU, Rowdy Creek

LOE ID:

102251

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances d colspan="2">

LOE ID:

120054

Pollutant:

Carbaryl

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (Water Quality Control Plan, North Coast Basin).

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA Health Advisory for carbaryl as a drinking water level with a one in a million cancer risk is 0.04 mg/L.

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0129)

Temporal Representation:

The samples were collected between the dates of 2013-08-07 and 2013-08-07

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157859, Carbaryl	Region 1
Smith River HU, Rowdy Creek

LOE ID:

102773

Pollutant:

Carbaryl

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (Water Quality Control Plan, North Coast Basin).

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA Health Advisory for lifetime exposure to Ammonia as a drinking water level is a concentration of 30 mg/L

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0129)

Temporal Representation:

The samples were collected between the dates of 2013-08-07 and 2013-08-07

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 104753, Ammonia	Region 1
Smith River HU, Rowdy Creek

LOE ID:

104263

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

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(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2015-03-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 104753, Ammonia

Region 1

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA Health Advisory for carbaryl as a drinking water level with a one in a million cancer risk is 0.04 mg/L.

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2015-03-23 and 2015-03-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157859, Carbaryl	Region 1
Smith River HU, Rowdy Creek

LOE ID:

115739

Pollutant:

Carbaryl

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA national ambient water quality criterion for freshwater aquatic life criterion continuous concentration expressed as a 4 day average for carbaryl is 2.1 µg/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2013-10-01 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157859, Carbaryl	Region 1
Smith River HU, Rowdy Creek

LOE ID:

104268

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

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(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2015-03-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 104753, Ammonia	Region 1
Smith River HU, Rowdy Creek

LOE ID:

101846

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Smith River HU, Rowdy Creek

LOE ID:

120053

Pollutant:

Carbaryl

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA national ambient water quality criterion for freshwater aquatic life criterion continuous concentration expressed as a 4 day average for carbaryl is 2.1 µg/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0129)

Temporal Representation:

The samples were collected between the dates of 2013-08-07 and 2013-08-07

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157859, Carbaryl	Region 1
Smith River HU, Rowdy Creek

LOE ID:

110934

Pollutant:

Carbaryl

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Basin: All waters shall be mainign="left" valign="top" width="33%">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(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2013-11-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 104753, Ammonia	Region 1
Smith River HU, Rowdy Creek

LOE ID:

108951

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

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(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2013-10-01 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 104753, Ammonia	Region 1
Smith River HU, Rowdy Creek

LOE ID:

111138

Pollutant:

Nitrogen, ammonia (Total Ammonia)

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA national ambient water quality criterion for freshwater aquatic life criterion continuous concentration expressed as a 4 day average for carbaryl is 2.1 µg/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2015-03-23 and 2015-03-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157859, Carbaryl	Region 1
Smith River HU, Rowdy Creek

LOE ID:

110936

Pollutant:

Carbaryl

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (Water Quality Control Plan, North Coast Basin).

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA Health Advisory for carbaryl as a drinking water level with a one in a million cancer risk is 0.04 mg/L.

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2015-03-23 and 2015-03-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

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 DFW_ABL_Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Ammonia as N.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for DFW_ABL_Monitoring.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA Health Advisory for lifetime exposure to Ammonia as a drinking water level is a concentration of 30 mg/L

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103FC1106)

Temporal Representation:

The samples were collected between the dates of 2014-07-15 and 2014-07-15

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 104753, Ammonia	Region 1
Smith River HU, Rowdy Creek

LOE ID:

102260

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA Health Advisory for lifetime exposure to Ammonia as a drinking water level is a concentration of 30 mg/L

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2013-10-01 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 104753, Ammonia	Region 1
Smith River HU, Rowdy Creek

LOE ID:

104270

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA Health Advisory for lifetime exposure to Ammonia as a drinking water level is a concentration of 30 mg/L

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2015-03-12 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 104753, Ammonia	Region 1
Smith River HU, Rowdy Creek

LOE ID:

118960

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA Health Advisory for lifetime exposure to Ammonia as a drinking water level is a concentration of 30 mg/L

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2015-03-11 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 104753, Ammonia	Region 1
Smith River HU, Rowdy Creek

LOE ID:

101848

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA Health Advisory for lifetime exposure to Ammonia as a drinking water level is a concentration of 30 mg/L

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0319)

Temporal Representation:

The samples were collected between the dates of 2013-11-05 and 2013-11-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	157860	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Carbofuran
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157860, Carbofuran	Region 1
Smith River HU, Rowdy Creek

LOE ID:

115744

Pollutant:

Carbofuran

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for Carbofuran incorporated by reference in the Water Quality Control Plan, North Coast Basin is 0.018 mg/L (Water Quality Control Plan, North Coast Basin).

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW0129)

Temporal Representation:

The samples were collected between the dates of 2013-08-07 and 2013-08-07

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157860, Carbofuran	Region 1
Smith River HU, Rowdy Creek

LOE ID:

107378

Pollutant:

Carbofuran

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for Carbofuran incorporated by reference in the Water Quality Control Plan, North Coast Basin is 0.018 mg/L (Water Quality Control Plan, North Coast Basin).

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (103RW1599)

Temporal Representation:

The samples were collected between the dates of 2015-06-23 and 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157860, Carbofuran	Region 1
Smith River HU, Rowdy Creek

LOE ID:

102778

Pollutant:

Carbofuran

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

DECISION ID

104134

Region 1

Smith River HU, Rowdy Creek

Pollutant:	Anthracene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line(s) of evidence are necessary to assess listing status. Two line(s) of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None samples exceeded the objective and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

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

Listing Extent:

Line of Evidence (LOE) for Decision ID 104134, Anthracene	Region 1
Smith River HU, Rowdy Creek

LOE ID:

121867

Pollutant:

Anthracene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for Anthrazene from MacDonald et al., 2000a which states that the probable effect concentration for Anthrazene is 845 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 103RW1599.

Temporal Representation:

Data for this waterbody were collected over the date range 2015-06-23 to 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 104134, Anthracene	Region 1
Smith River HU, Rowdy Creek

LOE ID:

121826

Pollutant:

Anthracene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

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:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The evaluation guideline for Anthrazene from MacDonald et al., 2000a which states that the probable effect concentration for Anthrazene is 845 ug/kg. (dw = Dry Weight)

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 103RW0319.

Temporal Representation:

Data for this waterbody were collected over the date range 2015-06-23 to 2015-06-23

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

="left" valign="top" width="67%">PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Carbofuran. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: The California Maximum Contaminant Level for Carbofuran incorporated by reference in the Water Quality Control Plan, North Coast Basin is 0.018 mg/L (Water Quality Control Plan, North Coast Basin). Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: Guideline Reference: Spatial Representation: The samples were collected at 1 monitoring site(s) (103RW0319) Temporal Representation: The samples were collected between the dates of 2015-06-23 and 2015-06-23 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157860, Carbofuran	Region 1
Smith River HU, Rowdy Creek

LOE ID: 120067 Pollutant: Carbofuran LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Municipal & Domestic Supply Number of Samples: 2 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Carbofuran. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: The California Maximum Contaminant Level for Carbofuran incorporated by reference in the Water Quality Control Plan, North Coast Basin is 0.018 mg/L (Water Quality Control Plan, North Coast Basin). Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: Guideline Reference: Spatial Representation: The samples were collected at 1 monitoring site(s) (103RW1599) Temporal Representation: The samples were collected between the dates of 2013-10-01 and 2013-11-05 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	100826	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Arsenic
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line(s) of evidence are necessary to assess listing status. Twelve lines of evidence are available in the administrative record to assess this pollutant. Zero of three sediment and water samples exceed the objective for protection of COLD and none of the sediment samples exhibit toxicity. Zero of three water samples exceed the objective for the protection of MUN. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of three sediment and water samples exceed the objective for protection of COLD and none of the sediment samples exhibit toxicity. Zero of three water samples exceed the objective for the protection of MUN. This sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to SECTION 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

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

Listing Extent:

Line of Evidence (LOE) for Decision ID 100826, Arsenic	Region 1
Smith River HU, Rowdy Creek

LOE ID:

120949

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitat"0" width="100%" cellspacing="0" cellpadding="0">

Line of Evidence (LOE) for Decision ID 157860, Carbofuran

Region 1

Smith River HU, Rowdy Creek

LOE ID: 323948 Pollutant: Carbofuran LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Municipal & Domestic Supply Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Carbofuran. Data Reference: Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1 SWAMP Data: SWAMP Water Quality Objective/Criterion: The California Maximum Contaminant Level for Carbofuran incorporated by reference in the Water Quality Control Plan, North Coast Basin is 0.018 mg/L (Water Quality Control Plan, North Coast Basin). Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: Guideline Reference: Spatial Representation: The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive). Temporal Representation: The samples were collected between the dates of 2017-06-08 and 2017-06-08 Environmental Conditions: QAPP Information: QAPP for Surface Water Ambient Monitoring Program (SWAMP) QAPP Information Reference(s): SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 157860, Carbofuran	Region 1
Smith River HU, Rowdy Creek

LOE ID: 323949 Pollutant: Carbofuran LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 0 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Carbofuran. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. Data Reference: Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1 SWAMP Data: SWAMP Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan). Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: The evaluation guideline for Carbofuran is the USEPA Aquatic Life Benchmark of 0.75 ug/L for an invertibrate (chronic). Guideline Reference: OPP Aquatic Life Benchmarks Spatial Representation: The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive). Temporal Representation: The samples were collected between the dates of 2017-06-08 and 2017-06-08 Environmental Conditions: QAPP Information: QAPP for Surface Water Ambient Monitoring Program (SWAMP) QAPP Information Reference(s): SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 157860, Carbofuran	Region 1
Smith River HU, Rowdy Creek

LOE ID: 118916 Pollutant: Carbofuran LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Municipal & Domestic Supply Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Carbofuran. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: The California Maximum Contaminant Level for Carbofuran incorporated by reference in the Water Quality Control Plan, North Coast Basin is 0.018 mg/L (Water Quality Control Plan, North Coast Basin). Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: Guideline Reference: Spatial Representation: The samples were collected at 1 monitoring site(s) (103RW1599) Temporal Representation: The samples were collected between the dates of 2015-03-23 and 2015-03-23 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157860, Carbofuran	Region 1
Smith River HU, Rowdy Creek

LOE ID: 118915 Pollutant: Carbofuran LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Municipal & Domestic Supply Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Carbofuran. Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: The California Maximum Contaminant Level for Carbofuran incorporated by reference in the Water Quality Control Plan, North Coast Basin is 0.018 mg/L (Water Quality Control Plan, North Coast Basin). Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: Guideline Reference: Spatial Representation: The samples were collected at 1 monitoring site(s) (103RW0319) Temporal Representation: The samples were collected between the dates of 2015-03-23 and 2015-03-23 Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	157861	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Carbon Disulfide
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157861, Carbon Disulfide	Region 1
Smith River HU, Rowdy Creek

LOE ID:

323951

Pollutant:

Carbon Disulfide

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 from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Drinking water notification levels are published by the Division of Drinking Water. Notification levels are for chemicals for which there is no drinking water MCL. If a notification level is exceeded, local government notification is required and customer notification is recommended. The notification level for Carbon Disulfide is 0.160 mg/L.

Guideline Reference:

Drinking Water Notification Levels and Response Levels

Spatial Representation:

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

Temporal Representation:

The samples were collected between the dates of 2017-06-08 and 2017-06-08

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Commercial or recreational collection of fish, shellfish, or organisms

ion cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Water Board(NCRWQCB 2018). Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: Guideline Reference: Spatial Representation: The samples were collected at 1 stations. Monitoring site(s): ( 103RW1599 ) Temporal Representation: The samples were collected between the dates of 2015-06-23 and 2015-06-23. Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 100826, Arsenic	Region 1
Smith River HU, Rowdy Creek

LOE ID: 121009 Pollutant: Toxicity LOE Subgroup: Toxicity Matrix: Sediment Fraction: None Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: TOXICITY TESTING Data Used to Assess Water Quality: 0 of the 1 samples collected by SWAMP RWB1 Irrigated Lands Monitoring for Smith River HU, Rowdy Creek exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Growth (wt/surv indiv), Hyalella azteca, for Survival Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Irrigated Lands Monitoring . SWAMP Data: SWAMP Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Water Board(NCRWQCB 2018). Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region Evaluation Guideline: Guideline Reference: Spatial Representation: The samples were collected at 1 stations. Monitoring site(s): ( 103RW0319 ) Temporal Representation: The samples were collected between the dates of 2015-06-23 and 2015-06-23. Environmental Conditions: QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP pro


DECISION ID	157862	Region 1
Smith River HU, Rowdy Creek

Pollutant:	Carbon Tetrachloride
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Listing Extent:

Line of Evidence (LOE) for Decision ID 157862, Carbon Tetrachloride	Region 1
Smith River HU, Rowdy Creek

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

The carbon tetrachloride criterion for the protection of human health from consumption of organisms only is 4.4 ug/L (California Toxics Rule, 2000).

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

The samples were collected between the dates of 2017-06-08 and 2017-06-08

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

Municipal & Domestic Supply

Line of Evidence (LOE) for Decision ID 157862, Carbon Tetrachloride	Region 1
Smith River HU, Rowdy Creek

Water Board staff assessed SWAMP RWB1 Irrigated Lands Monitoring data for Smith River HU, Rowdy Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Carbon Tetrachloride. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Field, Habitat, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

The carbon tetrachloride criterion for the protection of human health from the consumption of water and organisms is 0.25 ug/L (California Toxics Rule, 2000).

The samples were collected at 1 monitoring site: 103RW1599 (Rowdy Creek at South Fred Haight Drive).

The samples were collected between the dates of 2017-06-08 and 2017-06-08

QAPP for Surface Water Ambient Monitoring Program (SWAMP)