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

Supporting Information

Regional Board 4 - Los Angeles Region

Water Body Name:	San Gabriel River Reach 3 (Whittier Narrows to Ramona)
Water Body ID:	CAR4053100019980917153706
Water Body Type:	River & Stream


DECISION ID	138708	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

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:	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. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 0 of 43 samples exceeded the criteria and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138708, 1,1,2-Trichloroethane	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

256118

Pollutant:

1,1,2-Trichloroethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Trichloroethane, 1,1,2-.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region states that: Surface waters shall not contain concentrations of chemical constituents in amounts that adversely affect any designated beneficial use.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

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: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-02-05

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 138708, 1,1,2-Trichloroethane	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

256148

Pollutant:

1,1,2-Trichloroethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

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: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138708, 1,1,2-Trichloroethane	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

256102

Pollutant:

1,1,2-Trichloroethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

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: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-02-05

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program


DECISION ID	138690	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	2,4-D (2,4-Dichlorophenoxy acetic acid)
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. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 0 of 47 samples exceeded the criteria and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138690, 2,4-D (2,4-Dichlorophenoxy acetic acid)	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254459

Pollutant:

2,4-D (2,4-Dichlorophenoxy acetic acid)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The evaluation guideline for dichlorophenoxyacetic acid, 2,4- (2,4-D) is the USEPA Aquatic Life Benchmark of 299.2 ug/L for a vascular plant (acute).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138690, 2,4-D (2,4-Dichlorophenoxy acetic acid)	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254479

Pollutant:

2,4-D (2,4-Dichlorophenoxy acetic acid)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The evaluation guideline for dichlorophenoxyacetic acid, 2,4- (2,4-D) is the USEPA Aquatic Life Benchmark of 299.2 ug/L for a vascular plant (acute).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-05-27

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program


DECISION ID	138706	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

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:	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. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 0 of 43 samples exceeded the criteria and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138706, Acrolein	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

253420

Pollutant:

Acrolein

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

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: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138706, Acrolein	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

253485

Pollutant:

Acrolein

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

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: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-02-05

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138706, Acrolein	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

253503

Pollutant:

Acrolein

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

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: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-02-05

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program


DECISION ID	138707	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Aldrin
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. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 0 of 43 samples exceeded the guideline and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138707, Aldrin	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

253551

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-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: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138707, Aldrin	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

253595

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-02-05

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 138707, Aldrin	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

253549

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-02-05

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program


DECISION ID	138660	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Antimony
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. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 0 of 81 and 0 of 81 samples exceeded the criteria and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138660, Antimony	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

253406

Pollutant:

Antimony

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The USEPA Quality Criteria for Water (Gold Book) states that for antimony toxicity to algae occurs at 610 ug/l. (USEPA, 1986)

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: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138660, Antimony	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

253496

Pollutant:

Antimony

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The USEPA Quality Criteria for Water (Gold Book) states that for antimony toxicity to algae occurs at 610 ug/l. (USEPA, 1986)

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: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-05-27

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138660, Antimony	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

253322

Pollutant:

Antimony

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The USEPA Quality Criteria for Water (Gold Book) states that for antimony toxicity to algae occurs at 610 ug/l. (USEPA, 1986)

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: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-05-27

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138660, Antimony	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

253321

Pollutant:

Antimony

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The USEPA Quality Criteria for Water (Gold Book) states that for antimony toxicity to algae occurs at 610 ug/l. (USEPA, 1986)

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: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138660, Antimony	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

253559

Pollutant:

Antimony

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and results are as follows: 0 of 32 samples exceeded the water quality threshold for Antimony.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The USEPA Quality Criteria for Water (Gold Book) states that for antimony toxicity to algae occurs at 610 ug/l. (USEPA, 1986)

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: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-05-27

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 138660, Antimony	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

253454

Pollutant:

Antimony

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and results are as follows: 0 of 32 samples exceeded the water quality threshold for Antimony.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The USEPA Quality Criteria for Water (Gold Book) states that for antimony toxicity to algae occurs at 610 ug/l. (USEPA, 1986)

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: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-05-27

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program


DECISION ID	138661	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Arsenic
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:	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. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 0 of 68 and 0 of 82 samples exceeded the CRITERIA and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list 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.

Line of Evidence (LOE) for Decision ID 138661, Arsenic	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

253478

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and results are as follows: 0 of 33 samples exceeded the water quality threshold for Arsenic.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 150 ug/L. The conversion factor used to convert the total fraction criterion for arsenic to dissolved fraction criterion is 1. Therefore all data was considered to be representative of the dissolved fraction. (California Toxics Rule, 2000)

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-05-27

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 138661, Arsenic	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

87838

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

None of the 68 samples exceeded the criteria of 150 ug/L.

Data Reference:

Data for Various Pollutants in Various Water Bodies in Sanitation Districts of Los Angeles County, 2005-2010.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Surface waters shall not contain concentrations of chemical constituents in amounts that adversely affect any designated beneficial use.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The CTR for arsenic is 150 ug/L.

Guideline Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Spatial Representation:

Samples were collected from San Gabriel River Reach 3 (Whittier Narrows to Ramona) from location SJC also called SG (or SGR) at three sublocations: R10, R11 and RA (also called WN-RA).

Temporal Representation:

Samples were collected monthly from June 2006 through May of 2010.

Environmental Conditions:

QAPP Information:

The Biology Department of the San Jose Creek Water Quality Laboratory is responsible for collecting samples from receiving water stations along the San Gabriel River, Coyote Creek, San Jose Creek, Santa Clara River, and the Rio Hondo River. Data is collected for the Los Angeles Sanitation District NPDES permits. Some standard operating procedures for sampling were submitted, however no QA Project Plan was.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138661, Arsenic	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

253567

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138661, Arsenic	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

253413

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-05-27

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program


DECISION ID	138678	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

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.

Line of Evidence (LOE) for Decision ID 138678, Azinphos-methyl (Guthion)	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

253652

Pollutant:

Azinphos-methyl (Guthion)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) 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 7 samples were collected, 7 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:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region states that: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The USEPA National Recommended Water Quality Criteria for azinphos methyl for freshwater aquatic life protection is 0.01 ug/l (instantaneous maximum)

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-08-10 to 2014-08-05

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program


DECISION ID	138662	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Beryllium
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. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 0 of 81 and 0 of 81 samples exceeded the criteria and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138662, Beryllium	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

253923

Pollutant:

Beryllium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and results are as follows: 0 of 32 samples exceeded the water quality threshold for Beryllium.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The Gold Book states that beryllium chronic toxicity to freshwater aquatic life occur at concentrations as low as 5.3 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: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-05-27

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 138662, Beryllium	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

253901

Pollutant:

Beryllium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The Gold Book states that beryllium chronic toxicity to freshwater aquatic life occur at concentrations as low as 5.3 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: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138662, Beryllium	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

253819

Pollutant:

Beryllium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The Gold Book states that beryllium chronic toxicity to freshwater aquatic life occur at concentrations as low as 5.3 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: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-05-27

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138662, Beryllium	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

253946

Pollutant:

Beryllium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The Gold Book states that beryllium chronic toxicity to freshwater aquatic life occur at concentrations as low as 5.3 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: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-05-27

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138662, Beryllium	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

253902

Pollutant:

Beryllium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and results are as follows: 0 of 32 samples exceeded the water quality threshold for Beryllium.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The Gold Book states that beryllium chronic toxicity to freshwater aquatic life occur at concentrations as low as 5.3 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: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-05-27

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 138662, Beryllium	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

253900

Pollutant:

Beryllium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The Gold Book states that beryllium chronic toxicity to freshwater aquatic life occur at concentrations as low as 5.3 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: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program


DECISION ID	138663	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Boron
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. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 0 of 240 samples exceeded the criteria and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138663, Boron	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

243811

Pollutant:

Boron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed data from the San Jose Creek Water Reclamation Plant to determine beneficial use support. The results are as follows: 0 out of 94 samples exceed the criterion for Boron.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region list a site specific objective for Boron in the San Gabriel River Reach 3 (Whittier Narrows to Ramona) of 1 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Station RSW-004 (34.036528, -118.031083), located in San Gabriel River Reach 3 (Whittier Narrows to Ramona).

Temporal Representation:

The water samples were taken between 6/6/2011 - 7/1/2020, per the monitoring requirements listed in the San Jose Creek Water Reclamation Plant NPDES Permit monitoring and reporting program.

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the San Jose Creek Water Reclamation Plant NDPES Permit quality assurance provisions for water quality monitoring.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 138663, Boron	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

243910

Pollutant:

Boron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed data from the Whittier Narrows Water Reclamation Plant to determine beneficial use support. The results are as follows: 0 out of 94 samples exceed the criterion for Boron.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region list a site specific objective for Boron in the San Gabriel River Reach 3 (Whittier Narrows to Ramona) of 1 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Station RSW-001 (34.036111, -118.030861), located in San Gabriel River Reach 3 (Whittier Narrows to Ramona).

Temporal Representation:

The water samples were taken between 6/6/2011 - 7/1/2020, per the monitoring requirements listed in the Whittier Narrows Water Reclamation Plant NPDES Permit monitoring and reporting program.

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the Whittier Narrows Water Reclamation Plant NDPES Permit quality assurance provisions for water quality monitoring.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138663, Boron	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

243920

Pollutant:

Boron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed data from the Whittier Narrows Water Reclamation Plant to determine beneficial use support. The results are as follows: 0 out of 52 samples exceed the criterion for Boron.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region list a site specific objective for Boron in the San Gabriel River Reach 3 (Whittier Narrows to Ramona) of 1 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Station RSW-002 (34.022361, -118.054833), located in San Gabriel River Reach 3 (Whittier Narrows to Ramona).

Temporal Representation:

The water samples were taken between 6/6/2011 - 9/9/2020, per the monitoring requirements listed in the Whittier Narrows Water Reclamation Plant NPDES Permit monitoring and reporting program.

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the Whittier Narrows Water Reclamation Plant NDPES Permit quality assurance provisions for water quality monitoring.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program


DECISION ID	138664	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Cadmium
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:	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. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 0 of 74 and 0 of 239 samples exceeded the CRITERIA and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138664, Cadmium	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

87845

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

None of the 74 samples exceeded the hardness adjusted criteria.

Data Reference:

Data for Various Pollutants in Various Water Bodies in Sanitation Districts of Los Angeles County, 2005-2010.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Surface waters shall not contain concentrations of chemical constituents in amounts that adversely affect any designated beneficial use.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) 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. If no hardness data were available, a value of 100 mg/L was used.

Guideline Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Spatial Representation:

Samples were collected from San Gabriel River Reach 3 (Whittier Narrows to Ramona) from location SJC also called SG (or SGR) at three sublocations: R10, R11 and RA (also called WN-RA).

Temporal Representation:

Samples were collected monthly from June 2006 through May of 2010.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138664, Cadmium	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

253604

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved cadmium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is hardness dependent. The criterion when calculated using a default hardness of 100 mg/L is 2.2 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-06-06 and 2020-09-09

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138664, Cadmium	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

253732

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and results are as follows: 0 of 93 samples exceeded the water quality threshold for Cadmium.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-06-06 and 2020-07-01

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 138664, Cadmium	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

253664

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-06-06 and 2020-07-01

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program


DECISION ID	138665	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Chlordane
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.

Line of Evidence (LOE) for Decision ID 138665, Chlordane	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255997

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_Whittier Narrows Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Total Chlordane. Although a total of 17 samples were collected, 17 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:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The chlordane criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0043 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-08-10 to 2020-02-05

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138665, Chlordane	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255909

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_Whittier Narrows Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Total Chlordane. Although a total of 10 samples were collected, 10 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:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The chlordane criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0043 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-08-10 to 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138665, Chlordane	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

87846

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

The reporting limit for the non-detect sample was .05 ug/L which is greater than the evaluation guideline, therefore these data are not of sufficient resolution to determine if water quality standards are being achieved.

Data Reference:

Data for Various Pollutants in Various Water Bodies in Sanitation Districts of Los Angeles County, 2005-2010.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. Waters shall not contain substances in concentrations that result in the deposition of material that causes nuisance or adversely affects beneficial uses. (Water Quality Control Plan for the Coastal Watersheds of Los Angeles And Ventura Counties).

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The CTR CCC for Chlordane is 0.0043 ug/L.

Guideline Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Spatial Representation:

A total of two samples were collected at two locations, SGR_SJC_R-11 and SGR_WN_R-A. One sample was from SGR_SJC_R-11 and one sample was from SGR_WN_R-A.Location Description:SGR_SJC_R-11 is San Jose Creek Station RSW-004 (Station R-11). SGR_WN_R-A is Whittier Narrows Station RSW-002 (Station R-A)

Temporal Representation:

From both locations, the two water samples were collected in 2/16/2010.

Environmental Conditions:

There was no special environmental conditions reported.

QAPP Information:

An excel spreadsheet of laboratory information called "LIMS" which gave reporting limits for each analyte evaluated accompanied each data package.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138665, Chlordane	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

256019

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Total Chlordane. Although a total of 16 samples were collected, 16 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:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The chlordane criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0043 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-08-10 to 2020-02-05

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program


DECISION ID	138666	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. 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. 36 of 240 samples exceeded the objective and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138666, Chloride	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

243921

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed data from the Whittier Narrows Water Reclamation Plant to determine beneficial use support. The results are as follows: 4 out of 52 samples exceed the criterion for Chloride.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region list a site specific objective for Chloride in the San Gabriel River Reach 3 (Whittier Narrows to Ramona) of 150 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Station RSW-002 (34.022361, -118.054833), located in San Gabriel River Reach 3 (Whittier Narrows to Ramona).

Temporal Representation:

The water samples were taken between 6/6/2011 - 9/9/2020, per the monitoring requirements listed in the Whittier Narrows Water Reclamation Plant NPDES Permit monitoring and reporting program.

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the Whittier Narrows Water Reclamation Plant NDPES Permit quality assurance provisions for water quality monitoring.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138666, Chloride	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

243812

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed data from the San Jose Creek Water Reclamation Plant to determine beneficial use support. The results are as follows: 0 out of 94 samples exceed the criterion for Chloride.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region list a site specific objective for Chloride in the San Gabriel River Reach 3 (Whittier Narrows to Ramona) of 180 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Station RSW-004 (34.036528, -118.031083), located in San Gabriel River Reach 3 (Whittier Narrows to Ramona).

Temporal Representation:

The water samples were taken between 6/6/2011 - 7/1/2020, per the monitoring requirements listed in the San Jose Creek Water Reclamation Plant NPDES Permit monitoring and reporting program.

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the San Jose Creek Water Reclamation Plant NDPES Permit quality assurance provisions for water quality monitoring.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 138666, Chloride	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

243911

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed data from the Whittier Narrows Water Reclamation Plant to determine beneficial use support. The results are as follows: 32 out of 94 samples exceed the criterion for Chloride.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region list a site specific objective for Chloride in the San Gabriel River Reach 3 (Whittier Narrows to Ramona) of 150 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Station RSW-001 (34.036111, -118.030861), located in San Gabriel River Reach 3 (Whittier Narrows to Ramona).

Temporal Representation:

The water samples were taken between 6/6/2011 - 7/1/2020, per the monitoring requirements listed in the Whittier Narrows Water Reclamation Plant NPDES Permit monitoring and reporting program.

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the Whittier Narrows Water Reclamation Plant NDPES Permit quality assurance provisions for water quality monitoring.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program


DECISION ID	138668	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 138668, Chlorpyrifos	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

253834

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Chlorpyrifos. Although a total of 10 samples were collected, 10 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:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region states that: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The freshwater criterion continuous concentration to protect aquatic organisms is 0.015 ug/L (Siepmann and Finlayson 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005).

Guideline Reference:

Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game

Guideline Reference:

Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game (with minor corrections to significant figures as described in Beaulaurier et al., 2005).

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

Data for this waterbody were collected over the date range 2015-08-03 to 2020-02-03

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program


DECISION ID	138709	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Chromium
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:	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. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 0 of 84, 0 0f 1, 0 of 68 and 0 of 63 samples exceeded the CRITERIA and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138709, Chromium	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

87848

Pollutant:

Chromium, hexavalent

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

None of the 63 samples exceeded the criteria of 11 ug/L.

Data Reference:

Data for Various Pollutants in Various Water Bodies in Sanitation Districts of Los Angeles County, 2005-2010.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Surface waters shall not contain concentrations of chemical constituents in amounts that adversely affect any designated beneficial use.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The CTR for hexavalent chromium is 11 ug/L.

Guideline Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Spatial Representation:

Samples were collected from San Gabriel River Reach 3 (Whittier Narrows to Ramona) from location SJC also called SG (or SGR) at three sublocations: R10, R11 and RA (also called WN-RA).

Temporal Representation:

Samples were collected monthly from June 2006 through May of 2010.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138709, Chromium	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

253899

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved chromium (III) criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is is hardness dependent as described in Table 1 of paragraph (b)(1). The value calculated when using a default hardness of 100 mg/L is 180 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138709, Chromium	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254053

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chromium.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2015-02-04 and 2015-02-04

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 138709, Chromium	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

253938

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-05-27

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138709, Chromium	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254051

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and results are as follows: 0 of 33 samples exceeded the water quality threshold for Chromium.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-05-27

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 138709, Chromium	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

87847

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

None of the 68 samples exceeded the hardness adjusted criteria.

Data Reference:

Data for Various Pollutants in Various Water Bodies in Sanitation Districts of Los Angeles County, 2005-2010.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Surface waters shall not contain concentrations of chemical constituents in amounts that adversely affect any designated beneficial use.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Spatial Representation:

Samples were collected from San Gabriel River Reach 3 (Whittier Narrows to Ramona) from location SJC also called SG (or SGR) at three sublocations: R10, R11 and RA (also called WN-RA).

Temporal Representation:

Samples were collected monthly from June 2006 through May of 2010.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):


DECISION ID	138669	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Chromium, hexavalent
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. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 0 of 62 and 0 of 20 samples exceeded the criteria and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138669, Chromium, hexavalent	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254012

Pollutant:

Chromium, hexavalent

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved chromium (VI) criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater 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: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2013-08-12 and 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138669, Chromium, hexavalent	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254284

Pollutant:

Chromium, hexavalent

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Chromium VI.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved chromium (VI) criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater 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: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2015-05-04

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 138669, Chromium, hexavalent	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254266

Pollutant:

Chromium, hexavalent

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved chromium (VI) criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater 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: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2012-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138669, Chromium, hexavalent	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

253961

Pollutant:

Chromium, hexavalent

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved chromium (VI) criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater 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: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2013-08-12 and 2020-05-27

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138669, Chromium, hexavalent	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254287

Pollutant:

Chromium, hexavalent

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved chromium (VI) criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater 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: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2015-05-04

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138669, Chromium, hexavalent	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254311

Pollutant:

Chromium, hexavalent

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and results are as follows: 0 of 27 samples exceeded the water quality threshold for Chromium VI.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved chromium (VI) criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater 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: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2012-11-07 and 2020-05-27

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program


DECISION ID	138670	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Chromium, trivalent
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. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 0 of 84 samples exceeded the criteria and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138670, Chromium, trivalent	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254122

Pollutant:

Chromium, trivalent

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved chromium (III) criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is hardness dependent. The criterion when calculated using a default hardness of 100 mg/L is 180 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-05-27

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138670, Chromium, trivalent	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254149

Pollutant:

Chromium, trivalent

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138670, Chromium, trivalent	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254148

Pollutant:

Chromium, trivalent

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and results are as follows: 0 of 33 samples exceeded the water quality threshold for Chromium III.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-05-27

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program


DECISION ID	138671	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Copper
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:	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. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 2 of 352 samples exceeded the CRITERIA and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138671, Copper	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254225

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved copper criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is hardness dependent. The criterion when calculated using a default hardness of 100 mg/L is 9 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-06-06 and 2020-07-01

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138671, Copper	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254312

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and results are as follows: 1 of 94 samples exceeded the water quality threshold for Copper.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-06-06 and 2020-07-01

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 138671, Copper	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

87853

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

112

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

None of the 112 samples exceeded the hardness adjusted criteria.

Data Reference:

Data for Various Pollutants in Various Water Bodies in Sanitation Districts of Los Angeles County, 2005-2010.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Surface waters shall not contain concentrations of chemical constituents in amounts that adversely affect any designated beneficial use.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Spatial Representation:

Samples were collected from San Gabriel River Reach 3 (Whittier Narrows to Ramona) from location SJC also called SG (or SGR) at three sublocations: R10, R11 and RA (also called WN-RA).

Temporal Representation:

Samples were collected monthly from June 2006 through May of 2010.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138671, Copper	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254245

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-06-06 and 2020-09-09

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program


DECISION ID	138672	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Cyanide
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. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 0 of 81 samples exceeded the criteria and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138672, Cyanide	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254165

Pollutant:

Cyanide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and results are as follows: 0 of 32 samples exceeded the water quality threshold for Cyanide.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The cyanide criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 5.2 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-05-27

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 138672, Cyanide	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254164

Pollutant:

Cyanide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The cyanide criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 5.2 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138672, Cyanide	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254138

Pollutant:

Cyanide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The cyanide criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 5.2 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-05-27

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program


DECISION ID	149828	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 149828, DDT (Dichlorodiphenyltrichloroethane)	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254094

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for DDT(p,p'). Although a total of 16 samples were collected, 16 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:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The DDT(4,4') criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.001 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-08-10 to 2020-02-05

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 149828, DDT (Dichlorodiphenyltrichloroethane)	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254023

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_Whittier Narrows Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for DDT(p,p'). Although a total of 17 samples were collected, 17 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:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The DDT(4,4') criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.001 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-08-10 to 2020-02-05

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 149828, DDT (Dichlorodiphenyltrichloroethane)	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254049

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_Whittier Narrows Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for DDT(p,p'). Although a total of 10 samples were collected, 10 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:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The DDT(4,4') criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.001 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-08-10 to 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program


DECISION ID	138710	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 138710, Demeton	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254303

Pollutant:

Demeton

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Demeton, Total.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region states that: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The USEPA National Recommended Water Quality criterion for demeton for freshwater aquatic life protection is 0.1 ug/l (4 day average)

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2014-08-05

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program


DECISION ID	138674	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Diazinon
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:	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. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 0 of 87 and 0 of 4 samples exceeded the CRITERIA and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138674, Diazinon	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254565

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and results are as follows: 0 of 33 samples exceeded the water quality threshold for Diazinon.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region states that: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The freshwater chronic value for diazinon is 0.10 ug/L (4 day average)(Finlayson, 2004).

Guideline Reference:

Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-05-27

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 138674, Diazinon	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254497

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region states that: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The freshwater chronic value for diazinon is 0.10 ug/L (4 day average)(Finlayson, 2004).

Guideline Reference:

Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-05-27

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138674, Diazinon	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

87854

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

None of the four samples exceeded the evaluation guideline.

Data Reference:

Data for Various Pollutants in Various Water Bodies in Sanitation Districts of Los Angeles County, 2005-2010.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Region 4 Basin Plan objective is "No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses."

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The screening criteria is 0.05 ug/L, chronic 4-day average. Water quality criteria for Diazinon and Chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game.

Guideline Reference:

Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game

Spatial Representation:

A total of two samples were collected at two locations, SGR_SJC_R-11 and SGR_WN_R-A. One sample was from SGR_SJC_R-11 and one sample was from SGR_WN_R-A. Location Description:SGR_SJC_R-11 is San Jose Creek Station RSW-004 (Station R-11). SGR_WN_R-A is Whittier Narrows Station RSW-002 (Station R-A)

Temporal Representation:

Three samples at SGR_SJC_R-11 were collecte in 2/16/2010, 5/10/2010, and 11/09/2010 and one water sample at SGR_WN_R-A was collected in 2/16/2010.

Environmental Conditions:

There was no special environmental conditions reported.

QAPP Information:

An excel spreadsheet of laboratory information called "LIMS" which gave reporting limits for each analyte evaluated accompanied each data package.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138674, Diazinon	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254517

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region states that: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The freshwater chronic value for diazinon is 0.10 ug/L (4 day average)(Finlayson, 2004).

Guideline Reference:

Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-08-04

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program


DECISION ID	138675	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Dieldrin
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. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 0 of 43 samples exceeded the criteria and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138675, Dieldrin	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254668

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dieldrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.056 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-02-05

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138675, Dieldrin	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254644

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dieldrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.056 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138675, Dieldrin	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254594

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dieldrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.056 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-02-05

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program


DECISION ID	138676	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Endosulfan sulfate
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. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 0 of 42 samples exceeded the CRITERIA and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138676, Endosulfan sulfate	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254512

Pollutant:

Endosulfan sulfate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region states that: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The USEPA National Recommended Water Quality Criteria toxicity threshold for endosulfan sulfate for freshwater aquatic life protection is 0.056 ug/l (24 hour average)

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-02-05

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138676, Endosulfan sulfate	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254558

Pollutant:

Endosulfan sulfate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region states that: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The USEPA National Recommended Water Quality Criteria toxicity threshold for endosulfan sulfate for freshwater aquatic life protection is 0.056 ug/l (24 hour average)

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-02-05

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 138676, Endosulfan sulfate	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254515

Pollutant:

Endosulfan sulfate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region states that: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The USEPA National Recommended Water Quality Criteria toxicity threshold for endosulfan sulfate for freshwater aquatic life protection is 0.056 ug/l (24 hour average)

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program


DECISION ID	138677	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Endrin
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. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 0 of 43 samples exceeded the CRITERIA and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138677, Endrin	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254828

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The endrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.036 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-02-05

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138677, Endrin	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254357

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The endrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.036 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-02-05

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 138677, Endrin	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254786

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The endrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.036 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program


DECISION ID	138679	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 138679, Heptachlor	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254945

Pollutant:

Heptachlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_Whittier Narrows Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor. Although a total of 17 samples were collected, 17 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:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The heptachlor criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-08-10 to 2020-02-05

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138679, Heptachlor	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254986

Pollutant:

Heptachlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_Whittier Narrows Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor. Although a total of 10 samples were collected, 10 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:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The heptachlor criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-08-10 to 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138679, Heptachlor	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254984

Pollutant:

Heptachlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor. Although a total of 16 samples were collected, 16 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:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The heptachlor criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-08-10 to 2020-02-05

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program


DECISION ID	138680	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Heptachlor epoxide
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.

Line of Evidence (LOE) for Decision ID 138680, Heptachlor epoxide	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254903

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_Whittier Narrows Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor Epoxide. Although a total of 17 samples were collected, 17 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:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The heptachlor epoxide criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-08-10 to 2020-02-05

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138680, Heptachlor epoxide	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254901

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_Whittier Narrows Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor Epoxide. Although a total of 10 samples were collected, 10 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:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The heptachlor epoxide criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-08-10 to 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138680, Heptachlor epoxide	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254927

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor Epoxide. Although a total of 16 samples were collected, 16 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:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The heptachlor epoxide criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-08-10 to 2020-02-05

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 138680, Heptachlor epoxide	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

87943

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

The reporting limit for the non-detect sample was 0.01 ug/L which is equal to the water quality objective, therefore these data are not of sufficient resolution to determine if water quality standards are being achieved.

Data Reference:

Data for Various Pollutants in Various Water Bodies in Sanitation Districts of Los Angeles County, 2005-2010.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Region 4 Basin Plan objective is "No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

California Toxic Rule criteria fresh aquatic life protection continuous concentration (4-day average)is 0.0038 ug/L.

Guideline Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Spatial Representation:

Temporal Representation:

From both locations, the two water samples were collected in 2/16/2010.

Environmental Conditions:

There was no special environmental conditions reported.

QAPP Information:

An excel spreadsheet of laboratory information called "LIMS" which gave reporting limits for each analyte evaluated accompanied each data package.

QAPP Information Reference(s):


DECISION ID	138681	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Iron
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:	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. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 0 of 27, 1 of 27 and 3 of 64 samples exceeded the CRITERIA and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138681, Iron	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

87944

Pollutant:

Iron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Three of the 64 samples exceeded the criteria of 1,000 ug/L.

Data Reference:

Data for Various Pollutants in Various Water Bodies in Sanitation Districts of Los Angeles County, 2005-2010.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Surface waters shall not contain concentrations of chemical constituents in amounts that adversely affect any designated beneficial use.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

National Recommended Water Quality Criteria Continuous Concentrations are intended protect aquatic organisms from chronic exposures (expressed as 4-day average concentration) in freshwater. The evaluation guideline for iron is 1,000 ug/L to protect warm freshwater habitat.

Guideline Reference:

Spatial Representation:

Samples were collected from San Gabriel River Reach 3 (Whittier Narrows to Ramona) from location SJC also called SG (or SGR) at three sublocations: R10, R11 and RA (also called WN-RA).

Temporal Representation:

Samples were collected monthly from June 2006 through May of 2010.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138681, Iron	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254779

Pollutant:

Iron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

National Recommended Water Quality Criteria Continuous Concentrations are intended protect freshwater aquatic organisms from chronic exposures and are expressed as 4-day average concentrations. The evaluation guideline for Iron is 1,000 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-02-05

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138681, Iron	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254759

Pollutant:

Iron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-02-05

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138681, Iron	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254757

Pollutant:

Iron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138681, Iron	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254758

Pollutant:

Iron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program


DECISION ID	138682	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Lead
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:	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. 3 lines of evidence are available in the administrative record to assess this pollutant. 1 of the 272 samples exceed the criteria. 0 of the 1 samples exceed the criteria. 0 of the 112 samples exceed the criteria. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 1of 272, 0 of 1 and 0 of 112 samples exceeded the criteria and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138682, Lead	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

87945

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

112

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

None of the 112 samples exceeded the hardness adjusted criteria.

Data Reference:

Data for Various Pollutants in Various Water Bodies in Sanitation Districts of Los Angeles County, 2005-2010.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Surface waters shall not contain concentrations of chemical constituents in amounts that adversely affect any designated beneficial use.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Spatial Representation:

Samples were collected from San Gabriel River Reach 3 (Whittier Narrows to Ramona) from location SJC also called SG (or SGR) at three sublocations: R10, R11 and RA (also called WN-RA).

Temporal Representation:

Samples were collected monthly from June 2006 through May of 2010.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138682, Lead	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254723

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved lead criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is hardness dependent. The criterion when calculated using a default hardness of 100 mg/L is 2.5 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-06-06 and 2020-07-01

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138682, Lead	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254696

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-06-06 and 2020-09-09

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138682, Lead	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

25351

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Wildlife Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

One of 33 samples exceeded the California Toxics Rule Criterion Continuous Concentration for Lead and zero of 33 samples exceeded the Criterion Maximum Concentration. Water quality samples were taken and analyzed for Lead in accordance with the San Jose Creek Water Reclamation Plant permit monitoring and testing parameters.

Data Reference:

NPDES receiving water monitoring reports for Long Beach Water Reclamation Plant (NPDES No. CA0054119), Los Coyotes Water Reclamation Plant (NPDES No. CA0053716), Pomona Water Reclamation Plant (NPDES No. CA0053911), San Jose Creek Water Reclamation Plant (NPDES No. CA0053619), and Whittier Narrows Creek Water Reclamation Plant (NPDES No. CA0054011).

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Toxics Rule lists Criterion Continuous Concentrations for Lead to protect aquatic life in freshwater. The Lead criterion in freshwater is hardness dependent for each sample and varies based on the on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for metals criterion.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The Sanitation Districts of Los Angeles County conducted sampling in San Gabriel Reach 3 in the following receiving water monitoring stations: station R10 located upstream of San Jose Creek confluence (Lat: N34° 02¿ 22.5¿¿ Long: W118° 01¿ 29¿¿) and station R11 located downstream of San Jose Creek confluence (Lat: N34 02¿ 11.5¿¿ Long: W118° 01¿ 51.9¿¿).

Temporal Representation:

Grab samples were taken and analyzed on monthly basis from August 2004 to February 2007.

Environmental Conditions:

QAPP Information:

Data was collected in compliance with the sampling and monitoring procedures detailed in Sanitation Districts of Los Angeles County (NPDES No. CA0053911) Monitoring and Reporting Program.

QAPP Information Reference(s):

San Jose Creek Water Reclamation Plant Monitoring and Reporting Program for NPDES No. CA0053911 (County Sanitation Districts of Los Angeles County)

Line of Evidence (LOE) for Decision ID 138682, Lead	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255018

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Lead.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2015-02-04 and 2015-02-04

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 138682, Lead	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255095

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and results are as follows: 0 of 93 samples exceeded the water quality threshold for Lead.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-06-06 and 2020-07-01

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program


DECISION ID	138683	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
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. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 0 of 43 samples exceeded the criteria and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138683, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254796

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The gamma-BHC (Lindane, gamma-HCH) criterion maximum concentration to protect aquatic life in freshwater is 0.95 ug/L. (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-02-05

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138683, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254837

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The gamma-BHC (Lindane, gamma-HCH) criterion maximum concentration to protect aquatic life in freshwater is 0.95 ug/L. (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-02-05

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 138683, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254791

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The gamma-BHC (Lindane, gamma-HCH) criterion maximum concentration to protect aquatic life in freshwater is 0.95 ug/L. (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program


DECISION ID	138684	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Malathion
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:	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 are necessary to assess listing status. 1 line of evidence is available in the administrative record to assess this pollutant. 0 of 1 sample exceeded the CRITERIA. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 0 of 1 sample exceeded the CRITERIA 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.

Line of Evidence (LOE) for Decision ID 138684, Malathion	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255226

Pollutant:

Malathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Malathion. Although a total of 7 samples were collected, 7 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:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region states that: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Aquatic life should not be affected unacceptably if the 4-day average concentration of malathion does not exceed 0.028 ug/L (UC Davis Aquatic Life Criteria).

Guideline Reference:

Aquatic life water quality criteria derived via the UC Davis method: l. Organophosphate insecticides. Reviews of Environmental Contamination and Toxicology 216:1-48.

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-08-10 to 2014-08-05

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 138684, Malathion	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

87946

Pollutant:

Malathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

The sample did not exceed the water quality evaluation criteria guideline.

Data Reference:

Data for Various Pollutants in Various Water Bodies in Sanitation Districts of Los Angeles County, 2005-2010.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Region 4 Basin Plan objective is "No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses."

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The USEPA Nationally Recommended Criteria for fresh aquatic life protection continuous concentration (4-day average)is 0.1 ug/L.

Guideline Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Spatial Representation:

A total of two samples were collected at two locations, One sample was collected at SGR_SJC_R-11 Location Description:SGR_SJC_R-11 is San Jose Creek Station RSW-004 (Station R-11).

Temporal Representation:

From both locations, the two water samples were collected in 2/16/2010.

Environmental Conditions:

There was no special environmental conditions reported.

QAPP Information:

An excel spreadsheet of laboratory information called "LIMS" which gave reporting limits for each analyte evaluated accompanied each data package.

QAPP Information Reference(s):


DECISION ID	149829	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Mercury
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:	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. 3 lines of evidence are available in the administrative record to assess this pollutant. 0 of 198 samples exceeded the CRITERIA. 0 of 236 samples exceeded the CRITERIA. 0 of 94 samples exceeded the CRITERIA. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 0 of 198, 0 of 236 and 0 of 94 samples exceeded the CRITERIA and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 149829, Mercury	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

87952

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

None of the 94 samples exceeded the criteria of 0.77 ug/L.

Data Reference:

Data for Various Pollutants in Various Water Bodies in Sanitation Districts of Los Angeles County, 2005-2010.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Surface waters shall not contain concentrations of chemical constituents in amounts that adversely affect any designated beneficial use.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

National Recommended Water Quality Criteria Continuous Concentrations (4-day average concentrations) for freshwater aquatic organisms exposure to elemental mercury is 0.77 ug/L.

Guideline Reference:

Spatial Representation:

Samples were collected from San Gabriel River Reach 3 (Whittier Narrows to Ramona) from location SJC also called SG (or SGR) at three sublocations: R10, R11 and RA (also called WN-RA).

Temporal Representation:

Samples were collected monthly from June 2006 through May of 2010.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 149829, Mercury	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255186

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and results are as follows: 0 of 75 samples exceeded the water quality threshold for Mercury.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

National Recommended Water Quality Criteria Continuous Concentration (4-day average concentrations) for freshwater aquatic organisms exposure to total mercury is 0.77 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-06-06 and 2019-04-08

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 149829, Mercury	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255313

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

National Recommended Water Quality Criteria Continuous Concentration (4-day average concentrations) for freshwater aquatic organisms exposure to total mercury is 0.77 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-06-06 and 2018-06-11

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 149829, Mercury	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255097

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and results are as follows: 0 of 92 samples exceeded the water quality threshold for Mercury.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

National Recommended Water Quality Criteria Continuous Concentration (4-day average concentrations) for freshwater aquatic organisms exposure to total mercury is 0.77 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-06-06 and 2020-07-01

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 149829, Mercury	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255312

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

National Recommended Water Quality Criteria Continuous Concentration (4-day average concentrations) for freshwater aquatic organisms exposure to total mercury is 0.77 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-06-06 and 2020-09-09

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 149829, Mercury	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255123

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

National Recommended Water Quality Criteria Continuous Concentration (4-day average concentrations) for freshwater aquatic organisms exposure to total mercury is 0.77 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-06-06 and 2020-07-01

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 149829, Mercury	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255228

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

National Recommended Water Quality Criteria Continuous Concentration (4-day average concentrations) for freshwater aquatic organisms exposure to total mercury is 0.77 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-06-06 and 2019-04-08

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program


DECISION ID	138685	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Methoxychlor
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. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 0 of 81 samples exceeded the CRITERIA and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138685, Methoxychlor	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255172

Pollutant:

Methoxychlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The USEPA national ambient water quality criterion for freshwater aquatic life Criterion Continuous Concentration (CCC) expressed as a 4-day average for methoxychlor is 0.03 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138685, Methoxychlor	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255192

Pollutant:

Methoxychlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The USEPA national ambient water quality criterion for freshwater aquatic life Criterion Continuous Concentration (CCC) expressed as a 4-day average for methoxychlor is 0.03 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-05-27

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138685, Methoxychlor	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255191

Pollutant:

Methoxychlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and results are as follows: 0 of 32 samples exceeded the water quality threshold for Methoxychlor.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The USEPA national ambient water quality criterion for freshwater aquatic life Criterion Continuous Concentration (CCC) expressed as a 4-day average for methoxychlor is 0.03 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-05-27

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program


DECISION ID	138686	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 138686, Mirex	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255252

Pollutant:

Mirex

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Mirex. Although a total of 7 samples were collected, 7 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:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region states that: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The USEPA national recommended criterion continuous concentration for mirex for the protection of freshwater aquatic life is 0.001 µg/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-08-10 to 2014-08-05

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program


DECISION ID	138687	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Naphthalene
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. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 0 of 43 samples exceeded the criteria and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138687, Naphthalene	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255065

Pollutant:

Naphthalene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region states that: 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 Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The USEPA recommended naphthalene criterion for the protection of freshwater aquatic life is 620 ug/l. (EPA 440/5-80-059)

Guideline Reference:

Ambient Water Quality Criteria for Naphthalene

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-02-05

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 138687, Naphthalene	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255089

Pollutant:

Naphthalene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The USEPA recommended naphthalene criterion for the protection of freshwater aquatic life is 620 ug/l. (EPA 440/5-80-059)

Guideline Reference:

Ambient Water Quality Criteria for Naphthalene

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138687, Naphthalene	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255317

Pollutant:

Naphthalene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The USEPA recommended naphthalene criterion for the protection of freshwater aquatic life is 620 ug/l. (EPA 440/5-80-059)

Guideline Reference:

Ambient Water Quality Criteria for Naphthalene

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-02-05

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program


DECISION ID	138688	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Nickel
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:	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. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 0 of 68, 0 of 1 and 0 of 81 samples exceeded the CRITERIA and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138688, Nickel	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

87953

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

None of the 68 samples exceeded the hardness adjusted criteria.

Data Reference:

Data for Various Pollutants in Various Water Bodies in Sanitation Districts of Los Angeles County, 2005-2010.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Surface waters shall not contain concentrations of chemical constituents in amounts that adversely affect any designated beneficial use.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Spatial Representation:

Samples were collected from San Gabriel River Reach 3 (Whittier Narrows to Ramona) from location SJC also called SG (or SGR) at three sublocations: R10, R11 and RA (also called WN-RA).

Temporal Representation:

Samples were collected monthly from June 2006 through May of 2010.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138688, Nickel	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255129

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved nickel criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is hardness dependent. The criterion when calculated using a default hardness of 100 mg/L is 52 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138688, Nickel	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255219

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Nickel.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2015-02-04 and 2015-02-04

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 138688, Nickel	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255109

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-05-27

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138688, Nickel	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255107

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and results are as follows: 0 of 32 samples exceeded the water quality threshold for Nickel.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-05-27

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program


DECISION ID	138689	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Nitrate/Nitrite (Nitrite + Nitrate as N)
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. One line of evidence is available in the administrative record to assess this pollutant. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 15 of 124 samples exceeded the objective and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138689, Nitrate/Nitrite (Nitrite + Nitrate as N)	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

243922

Pollutant:

Nitrate/Nitrite (Nitrite + Nitrate as N)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed data from the Whittier Narrows Water Reclamation Plant to determine beneficial use support. The results are as follows: 2 out of 28 samples exceed the criterion for Nitrate + Nitrite as N.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region list a site specific objective for Nitrate + Nitrite as N in the San Gabriel River Reach 3 (Whittier Narrows to Ramona) of 8 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Station RSW-002 (34.022361, -118.054833), located in San Gabriel River Reach 3 (Whittier Narrows to Ramona).

Temporal Representation:

The water samples were taken between 2/4/2015 - 9/9/2020, per the monitoring requirements listed in the Whittier Narrows Water Reclamation Plant NPDES Permit monitoring and reporting program.

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the Whittier Narrows Water Reclamation Plant NDPES Permit quality assurance provisions for water quality monitoring.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138689, Nitrate/Nitrite (Nitrite + Nitrate as N)	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

243813

Pollutant:

Nitrate/Nitrite (Nitrite + Nitrate as N)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed data from the San Jose Creek Water Reclamation Plant to determine beneficial use support. The results are as follows: 7 out of 47 samples exceed the criterion for Nitrate + Nitrite as N.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region list a site specific objective for Nitrate + Nitrite as N in the San Gabriel River Reach 3 (Whittier Narrows to Ramona) of 8 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Station RSW-004 (34.036528, -118.031083), located in San Gabriel River Reach 3 (Whittier Narrows to Ramona).

Temporal Representation:

The water samples were taken between 6/22/2015 - 7/1/2020, per the monitoring requirements listed in the San Jose Creek Water Reclamation Plant NPDES Permit monitoring and reporting program.

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the San Jose Creek Water Reclamation Plant NDPES Permit quality assurance provisions for water quality monitoring.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 138689, Nitrate/Nitrite (Nitrite + Nitrate as N)	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

243912

Pollutant:

Nitrate/Nitrite (Nitrite + Nitrate as N)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed data from the Whittier Narrows Water Reclamation Plant to determine beneficial use support. The results are as follows: 6 out of 49 samples exceed the criterion for Nitrate + Nitrite as N.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region list a site specific objective for Nitrate + Nitrite as N in the San Gabriel River Reach 3 (Whittier Narrows to Ramona) of 8 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Station RSW-001 (34.036111, -118.030861), located in San Gabriel River Reach 3 (Whittier Narrows to Ramona).

Temporal Representation:

The water samples were taken between 2/4/2015 - 7/1/2020, per the monitoring requirements listed in the Whittier Narrows Water Reclamation Plant NPDES Permit monitoring and reporting program.

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the Whittier Narrows Water Reclamation Plant NDPES Permit quality assurance provisions for water quality monitoring.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program


DECISION ID	149830	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 2 of 156 samples exceeded the objective and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 149830, Nitrogen, Nitrate	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

302612

Pollutant:

Nitrogen, Nitrate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and results are as follows: 1 of 73 samples exceeded the water quality threshold for Nitrate as N.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region (page 3-34) states that: Waters shall not exceed 10 mg/L as nitrate-nitrogen (NO3-N).

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-06-06 and 2018-04-05

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 149830, Nitrogen, Nitrate	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

302572

Pollutant:

Nitrogen, Nitrate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region (page 3-34) states that: Waters shall not exceed 10 mg/L as nitrate-nitrogen (NO3-N).

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2015-01-05 and 2020-07-01

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 149830, Nitrogen, Nitrate	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

302573

Pollutant:

Nitrogen, Nitrate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region (page 3-34) states that: Waters shall not exceed 10 mg/L as nitrate-nitrogen (NO3-N).

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2015-02-04 and 2020-09-09

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program


DECISION ID	138691	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Organophosphate Pesticides
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. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 0 of 87 samples exceeded the GUIDELINE and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138691, Organophosphate Pesticides	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255718

Pollutant:

Organophosphate Pesticides

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region states that: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The evaluation guideline for the protection of aquatic life from the additive effects of the organophosphate pesticides chlorpyrifos and diazinon is one toxic unit equivalent. A toxic unit equivalent is equal to the sum of chlorpyrifos and diazinon from a single sample, each having their reported concentration divided their respective evaluation guideline prior to being summed. If this results in a value greater than one, the sample is considered to be in exceedance of the water quality standard. (Bailey et al., 1997).

Guideline Reference:

Joint acute toxicity of Diazinon and Chlorpyrifos to Ceriodaphnia dubia.

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-05-27

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138691, Organophosphate Pesticides	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255655

Pollutant:

Organophosphate Pesticides

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region states that: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Joint acute toxicity of Diazinon and Chlorpyrifos to Ceriodaphnia dubia.

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-08-04

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138691, Organophosphate Pesticides	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255633

Pollutant:

Organophosphate Pesticides

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and results are as follows: 0 of 33 samples exceeded the water quality threshold for Organophosphorus Pesticides.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region states that: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Joint acute toxicity of Diazinon and Chlorpyrifos to Ceriodaphnia dubia.

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-05-27

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program


DECISION ID	151919	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Oxygen, Dissolved
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:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Four lines of evidence is available in the administrative record to assess this pollutant. 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. 17 of 447samples exceeded the OBJECTIVE and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 151919, Oxygen, Dissolved	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

87956

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

207

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Numeric data generated from 207 averages of Dissolved Oxygen concentrations had two exceedances.

Data Reference:

Data for Various Pollutants in Various Water Bodies in Sanitation Districts of Los Angeles County, 2005-2010.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Dissolved Oxygen Water Quality Objective of all surface waters designated as Warm Fresh Water Aquatic Habitat shall not be depressed below 5 mg/l.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from the SJC-R10, SJC/WN-R11, and WN-RA stations.

Temporal Representation:

Samples were collected approximately once a month from July 2005 to November 2009.

Environmental Conditions:

QAPP Information:

NPDES quality assurance.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 151919, Oxygen, Dissolved	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

308002

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region (page 3-39) states that: The dissolved oxygen content of all surface waters designated as WARM shall not be depressed below 5 mg/L as a result of waste discharges.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-06-06 and 2020-09-09

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 151919, Oxygen, Dissolved	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

308104

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and results are as follows: 6 of 94 samples exceeded the water quality threshold for Oxygen, Dissolved.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-06-06 and 2020-07-01

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 151919, Oxygen, Dissolved	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

308054

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-06-06 and 2020-07-01

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program


DECISION ID	138696	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 138696, PCBs (Polychlorinated biphenyls)	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255724

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_Whittier Narrows Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for PCBs (Polychlorinated biphenyls). Although a total of 10 samples were collected, 10 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:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The PCB, total aroclors criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.014 ug/L. This value corresponds to the sum of aroclors 1242, 1254, 1221, 1232, 1248, 1260, and 1016 (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-08-10 to 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138696, PCBs (Polychlorinated biphenyls)	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255400

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_Whittier Narrows Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for PCBs (Polychlorinated biphenyls). Although a total of 17 samples were collected, 17 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:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-08-10 to 2020-02-05

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138696, PCBs (Polychlorinated biphenyls)	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255616

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for PCBs (Polychlorinated biphenyls). Although a total of 16 samples were collected, 16 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:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-08-10 to 2020-02-05

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program


DECISION ID	138693	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Parathion
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:	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 are necessary to assess listing status. 1 line of evidence is available in the administrative record to assess this pollutant. 0 of 0 sample exceeded the CRITERIA. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 0 of 0 sample exceeded the CRITERIA 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.

Line of Evidence (LOE) for Decision ID 138693, Parathion	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255443

Pollutant:

Parathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Parathion, Ethyl. Although a total of 7 samples were collected, 7 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:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region states that: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The USEPA recommended freshwater aquatic life ambient water quality chronic criteria for parathion is 0.013 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-08-10 to 2014-08-05

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 138693, Parathion	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

87961

Pollutant:

Parathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

The reporting limit for the non-detect sample was 0.25 ug/L which is greater than the evaluation guideline, therefore these data are not of sufficient resolution to determine if water quality standards are being achieved.

Data Reference:

Data for Various Pollutants in Various Water Bodies in Sanitation Districts of Los Angeles County, 2005-2010.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Region 4 Basin Plan objective is "No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses."

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Freshwater Aquatic Life Protection Recommended Criteria Continuous Concentration 4-day Average) is 0.013 ug/L.

Guideline Reference:

Spatial Representation:

One sample was collected at SGR_SJC_R-11 Location Description:SGR_SJC_R-11 is San Jose Creek Station RSW-004 (Station R-11).

Temporal Representation:

From both locations, the two water samples were collected in 2/16/2010.

Environmental Conditions:

There was no special environmental conditions reported.

QAPP Information:

An excel spreadsheet of laboratory information called "LIMS" which gave reporting limits for each analyte evaluated accompanied each data package.

QAPP Information Reference(s):


DECISION ID	138694	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Pentachlorophenol (PCP)
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. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 0 of 43 samples exceeded the criteria and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138694, Pentachlorophenol (PCP)	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255539

Pollutant:

Pentachlorophenol (PCP)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The pentachlorophenol criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is pH dependent. The criterion using a default pH value of 7.8 (when pH data is not present) is 15 ug/L. (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-02-05

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 138694, Pentachlorophenol (PCP)	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255620

Pollutant:

Pentachlorophenol (PCP)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-02-05

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138694, Pentachlorophenol (PCP)	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255606

Pollutant:

Pentachlorophenol (PCP)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program


DECISION ID	138697	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Selenium
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:	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. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 0 of 203, 0 of 203 and 0 of 95 samples exceeded the CRITERIA and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138697, Selenium	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255412

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 5 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-06-06 and 2020-07-01

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138697, Selenium	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255711

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 5 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138697, Selenium	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255388

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and results are as follows: 0 of 93 samples exceeded the water quality threshold for Selenium.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 5 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-06-06 and 2020-07-01

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 138697, Selenium	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255653

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 5 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-06-06 and 2020-07-01

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138697, Selenium	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255710

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and results are as follows: 0 of 93 samples exceeded the water quality threshold for Selenium.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 5 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-06-06 and 2020-07-01

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 138697, Selenium	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255824

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 5 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138697, Selenium	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

87963

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

None of the 95 samples exceeded the criteria of 5 ug/L.

Data Reference:

Data for Various Pollutants in Various Water Bodies in Sanitation Districts of Los Angeles County, 2005-2010.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Surface waters shall not contain concentrations of chemical constituents in amounts that adversely affect any designated beneficial use.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The CTR for selenium is 5.0 ug/L.

Guideline Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Spatial Representation:

Samples were collected from San Gabriel River Reach 3 (Whittier Narrows to Ramona) from location SJC also called SG (or SGR) at three sublocations: R10, R11 and RA (also called WN-RA).

Temporal Representation:

Samples were collected monthly from June 2006 through May of 2010.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):


DECISION ID	138698	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Silver
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:	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. 1 line of evidence is available in the administrative record to assess this pollutant. 0 of 185 samples exceeded the CRITERIA. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 0 of 185 samples exceeded the CRITERIA and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138698, Silver	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255788

Pollutant:

Silver

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and results are as follows: 0 of 32 samples exceeded the water quality threshold for Silver.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved silver criterion maximum concentration (CMC) to protect aquatic life in freshwater is hardnesss dependent. The criterion when calculated using a default hardness of 100 mg/L is 3.4 ug/L. This criterion 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: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-05-27

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 138698, Silver	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255763

Pollutant:

Silver

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138698, Silver	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255747

Pollutant:

Silver

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-05-27

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138698, Silver	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

87964

Pollutant:

Silver

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

104

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

None of the 104 samples exceeded the hardness adjusted criteria.

Data Reference:

Data for Various Pollutants in Various Water Bodies in Sanitation Districts of Los Angeles County, 2005-2010.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Surface waters shall not contain concentrations of chemical constituents in amounts that adversely affect any designated beneficial use.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

California Toxics Rule (CTR) lists criterion maximum concentrations for silver to protect aquatic life in freshwater (1-hour average). The silver 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. If no hardness data were available, a value of 100 mg/L was used.

Guideline Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Spatial Representation:

Samples were collected from San Gabriel River Reach 3 (Whittier Narrows to Ramona) from location SJC also called SG (or SGR) at three sublocations: R10, R11 and RA (also called WN-RA).

Temporal Representation:

Samples were collected monthly from June 2006 through May of 2010.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):


DECISION ID	138699	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. 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. 0 of 240 samples exceeded the objective and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138699, Sulfates	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

243923

Pollutant:

Sulfates

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed data from the Whittier Narrows Water Reclamation Plant to determine beneficial use support. The results are as follows: 0 out of 52 samples exceed the criterion for Sulfate.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region list a site specific objective for Sulfate in the San Gabriel River Reach 3 (Whittier Narrows to Ramona) of 300 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Station RSW-002 (34.022361, -118.054833), located in San Gabriel River Reach 3 (Whittier Narrows to Ramona).

Temporal Representation:

The water samples were taken between 6/6/2011 - 9/9/2020, per the monitoring requirements listed in the Whittier Narrows Water Reclamation Plant NPDES Permit monitoring and reporting program.

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the Whittier Narrows Water Reclamation Plant NDPES Permit quality assurance provisions for water quality monitoring.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138699, Sulfates	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

243913

Pollutant:

Sulfates

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed data from the Whittier Narrows Water Reclamation Plant to determine beneficial use support. The results are as follows: 0 out of 94 samples exceed the criterion for Sulfate.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region list a site specific objective for Sulfate in the San Gabriel River Reach 3 (Whittier Narrows to Ramona) of 300 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Station RSW-001 (34.036111, -118.030861), located in San Gabriel River Reach 3 (Whittier Narrows to Ramona).

Temporal Representation:

The water samples were taken between 6/6/2011 - 7/1/2020, per the monitoring requirements listed in the Whittier Narrows Water Reclamation Plant NPDES Permit monitoring and reporting program.

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the Whittier Narrows Water Reclamation Plant NDPES Permit quality assurance provisions for water quality monitoring.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138699, Sulfates	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

243814

Pollutant:

Sulfates

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed data from the San Jose Creek Water Reclamation Plant to determine beneficial use support. The results are as follows: 0 out of 94 samples exceed the criterion for Sulfate.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region list a site specific objective for Sulfate in the San Gabriel River Reach 3 (Whittier Narrows to Ramona) of 300 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Station RSW-004 (34.036528, -118.031083), located in San Gabriel River Reach 3 (Whittier Narrows to Ramona).

Temporal Representation:

The water samples were taken between 6/6/2011 - 7/1/2020, per the monitoring requirements listed in the San Jose Creek Water Reclamation Plant NPDES Permit monitoring and reporting program.

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the San Jose Creek Water Reclamation Plant NDPES Permit quality assurance provisions for water quality monitoring.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program


DECISION ID	138701	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Thallium
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. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 0 of 81 and 0 of 81 samples exceeded the criteria and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138701, Thallium	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255772

Pollutant:

Thallium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The USEPA Quality Criteria for Water (Gold Book) states that thallium chronic toxicity to one species of fish occurs at concentrations as low as 20 ug/L after 2,600 hours of exposure. (USEPA, 1986)

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: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-05-27

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138701, Thallium	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255774

Pollutant:

Thallium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and results are as follows: 0 of 32 samples exceeded the water quality threshold for Thallium.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The USEPA Quality Criteria for Water (Gold Book) states that thallium chronic toxicity to one species of fish occurs at concentrations as low as 20 ug/L after 2,600 hours of exposure. (USEPA, 1986)

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: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-05-27

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 138701, Thallium	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255756

Pollutant:

Thallium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The USEPA Quality Criteria for Water (Gold Book) states that thallium chronic toxicity to one species of fish occurs at concentrations as low as 20 ug/L after 2,600 hours of exposure. (USEPA, 1986)

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: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-05-27

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138701, Thallium	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255736

Pollutant:

Thallium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The USEPA Quality Criteria for Water (Gold Book) states that thallium chronic toxicity to one species of fish occurs at concentrations as low as 20 ug/L after 2,600 hours of exposure. (USEPA, 1986)

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: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138701, Thallium	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

256034

Pollutant:

Thallium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The USEPA Quality Criteria for Water (Gold Book) states that thallium chronic toxicity to one species of fish occurs at concentrations as low as 20 ug/L after 2,600 hours of exposure. (USEPA, 1986)

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: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138701, Thallium	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255767

Pollutant:

Thallium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and results are as follows: 0 of 32 samples exceeded the water quality threshold for Thallium.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The USEPA Quality Criteria for Water (Gold Book) states that thallium chronic toxicity to one species of fish occurs at concentrations as low as 20 ug/L after 2,600 hours of exposure. (USEPA, 1986)

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: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-05-27

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program


DECISION ID	138702	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Total Dissolved Solids
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 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. 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. 27 of 240 samples exceeded the objective and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138702, Total Dissolved Solids	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

243924

Pollutant:

Total Dissolved Solids

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed data from the Whittier Narrows Water Reclamation Plant to determine beneficial use support. The results are as follows: 1 out of 52 samples exceed the criterion for Total Dissolved Solids.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region list a site specific objective for Total Dissolved Solids in the San Gabriel River Reach 3 (Whittier Narrows to Ramona) of 750 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Station RSW-002 (34.022361, -118.054833), located in San Gabriel River Reach 3 (Whittier Narrows to Ramona).

Temporal Representation:

The water samples were taken between 6/6/2011 - 9/9/2020, per the monitoring requirements listed in the Whittier Narrows Water Reclamation Plant NPDES Permit monitoring and reporting program.

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the Whittier Narrows Water Reclamation Plant NDPES Permit quality assurance provisions for water quality monitoring.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138702, Total Dissolved Solids	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

243815

Pollutant:

Total Dissolved Solids

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed data from the San Jose Creek Water Reclamation Plant to determine beneficial use support. The results are as follows: 13 out of 94 samples exceed the criterion for Total Dissolved Solids.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region list a site specific objective for Total Dissolved Solids in the San Gabriel River Reach 3 (Whittier Narrows to Ramona) of 750 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Station RSW-004 (34.036528, -118.031083), located in San Gabriel River Reach 3 (Whittier Narrows to Ramona).

Temporal Representation:

The water samples were taken between 6/6/2011 - 7/1/2020, per the monitoring requirements listed in the San Jose Creek Water Reclamation Plant NPDES Permit monitoring and reporting program.

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the San Jose Creek Water Reclamation Plant NDPES Permit quality assurance provisions for water quality monitoring.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 138702, Total Dissolved Solids	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

243919

Pollutant:

Total Dissolved Solids

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed data from the Whittier Narrows Water Reclamation Plant to determine beneficial use support. The results are as follows: 13 out of 94 samples exceed the criterion for Total Dissolved Solids.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region list a site specific objective for Total Dissolved Solids in the San Gabriel River Reach 3 (Whittier Narrows to Ramona) of 750 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Station RSW-001 (34.036111, -118.030861), located in San Gabriel River Reach 3 (Whittier Narrows to Ramona).

Temporal Representation:

The water samples were taken between 6/6/2011 - 7/1/2020, per the monitoring requirements listed in the Whittier Narrows Water Reclamation Plant NPDES Permit monitoring and reporting program.

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the Whittier Narrows Water Reclamation Plant NDPES Permit quality assurance provisions for water quality monitoring.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program


DECISION ID	138703	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Toxaphene
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.

Line of Evidence (LOE) for Decision ID 138703, Toxaphene	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

256143

Pollutant:

Toxaphene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_Whittier Narrows Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Toxaphene. Although a total of 10 samples were collected, 10 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:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The toxaphene criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0002 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-08-10 to 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138703, Toxaphene	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

87966

Pollutant:

Toxaphene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Since the criteria is smaller than the reporting limit and method detection limit, none of samples can be counted.

Data Reference:

Data for Various Pollutants in Various Water Bodies in Sanitation Districts of Los Angeles County, 2005-2010.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Los Angeles Region Basin Plan objective is "No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses."

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Criteria Continuous Concentration (4-day Average) is 0.0002 ug/L

Guideline Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Spatial Representation:

A total of two samples were collected at two locations, One sample was collected at SGR_SJC_R-11 Location Description:SGR_SJC_R-11 is San Jose Creek Station RSW-004 (Station R-11).

Temporal Representation:

From both locations, the two water samples were collected in 2/16/2010.

Environmental Conditions:

There was no special environmental conditions reported.

QAPP Information:

An excel spreadsheet of laboratory information called "LIMS" which gave reporting limits for each analyte evaluated accompanied each data package.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138703, Toxaphene	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

256230

Pollutant:

Toxaphene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_Whittier Narrows Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Toxaphene. Although a total of 17 samples were collected, 17 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:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The toxaphene criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0002 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-08-10 to 2020-02-05

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138703, Toxaphene	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

256130

Pollutant:

Toxaphene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Toxaphene. Although a total of 16 samples were collected, 16 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:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The toxaphene criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0002 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-08-10 to 2020-02-05

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program


DECISION ID	138704	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. 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. 4 of 193 samples exceeded the OBJECTIVE and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138704, Turbidity	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

256304

Pollutant:

Turbidity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and results are as follows: 1 of 47 samples exceeded the water quality threshold for Turbidity.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region states that: Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Turbidities of 40 NTU or greater can cause a reduced foraging efficiency and a shift in prey selection in piscivorous fish (largemouth bass) due to interference with their ability to find prey (Shoup, D.E. and Wahl D.H., 2009).

Guideline Reference:

The Effects of Turbidity on Prey Selection by Piscivorous Largemouth Bass

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2015-06-22 and 2020-07-01

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 138704, Turbidity	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

256247

Pollutant:

Turbidity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region states that: Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

The Effects of Turbidity on Prey Selection by Piscivorous Largemouth Bass

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-06-06 and 2020-09-09

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138704, Turbidity	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

256269

Pollutant:

Turbidity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region states that: Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

The Effects of Turbidity on Prey Selection by Piscivorous Largemouth Bass

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-06-06 and 2020-07-01

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program


DECISION ID	138705	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Zinc
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:	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. 1 line of evidence is available in the administrative record to assess this pollutant. 1 of 352 samples exceeded the CRITERIA. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 1 of 352 samples exceeded the CRITERIA and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138705, Zinc	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

87971

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

112

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

None of the 112 samples exceeded the hardness adjusted criteria.

Data Reference:

Data for Various Pollutants in Various Water Bodies in Sanitation Districts of Los Angeles County, 2005-2010.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Surface waters shall not contain concentrations of chemical constituents in amounts that adversely affect any designated beneficial use.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Spatial Representation:

Samples were collected from San Gabriel River Reach 3 (Whittier Narrows to Ramona) from location SJC also called SG (or SGR) at three sublocations: R10, R11 and RA (also called WN-RA).

Temporal Representation:

Samples were collected monthly from June 2006 through May of 2010.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138705, Zinc	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

256207

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and results are as follows: 0 of 94 samples exceeded the water quality threshold for Zinc.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved zinc criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is hardness dependent. The criterion when calculated using a default hardness of 100 mg/L is 120 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-06-06 and 2020-07-01

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 138705, Zinc	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

256205

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-06-06 and 2020-07-01

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138705, Zinc	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

256140

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-06-06 and 2020-09-09

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program


DECISION ID	138673	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	alpha-Endosulfan (Endosulfan 1)
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. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 0 of 43 samples exceeded the CRITERIA and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138673, alpha-Endosulfan (Endosulfan 1)	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254534

Pollutant:

alpha-Endosulfan (Endosulfan 1)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The endosulfan I (alpha-endosulfan) criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.056 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138673, alpha-Endosulfan (Endosulfan 1)	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254599

Pollutant:

alpha-Endosulfan (Endosulfan 1)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The endosulfan I (alpha-endosulfan) criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.056 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-02-05

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138673, alpha-Endosulfan (Endosulfan 1)	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254674

Pollutant:

alpha-Endosulfan (Endosulfan 1)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The endosulfan I (alpha-endosulfan) criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.056 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-02-05

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program


DECISION ID	138692	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	beta-Endosulfan (Endosulfan 2)
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. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 0 of 43 samples exceeded the CRITERIA and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138692, beta-Endosulfan (Endosulfan 2)	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254423

Pollutant:

beta-Endosulfan (Endosulfan 2)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The endosulfan II (beta-endosulfan) criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.056 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-02-05

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138692, beta-Endosulfan (Endosulfan 2)	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254374

Pollutant:

beta-Endosulfan (Endosulfan 2)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The endosulfan II (beta-endosulfan) criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.056 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-08-06

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138692, beta-Endosulfan (Endosulfan 2)	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

254369

Pollutant:

beta-Endosulfan (Endosulfan 2)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The endosulfan II (beta-endosulfan) criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.056 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-08-10 and 2020-02-05

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program


DECISION ID	138695	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	pH
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
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 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. 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. 10 of 405 samples exceeded the OBJECTIVE and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138695, pH	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

87962

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

164

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Two of the 164 samples exceeded the objective.

Data Reference:

Data for Various Pollutants in Various Water Bodies in Sanitation Districts of Los Angeles County, 2005-2010.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The pH of all inland surface waters shall not be depressed below 6.5 or raised above 8.5 as a result of waste discharges.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from the SG-R10, SG-R11, and WN-RA stations

Temporal Representation:

Samples were collected approximately once a month from July 2005 to November 2009.

Environmental Conditions:

QAPP Information:

NPDES quality assurance.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138695, pH	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255500

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, Los Angeles Basin: the pH for inland surface waters, bays, or estuaries shall not be depressed below 6.5 or raised above 8.5 as a result of waste discharges.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-06-06 and 2020-09-09

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138695, pH	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255430

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, Los Angeles Basin: the pH for inland surface waters, bays, or estuaries shall not be depressed below 6.5 or raised above 8.5 as a result of waste discharges.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-06-06 and 2020-07-01

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138695, pH	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255706

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and results are as follows: 4 of 94 samples exceeded the water quality threshold for pH.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, Los Angeles Basin: the pH for inland surface waters, bays, or estuaries shall not be depressed below 6.5 or raised above 8.5 as a result of waste discharges.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-06-06 and 2020-07-01

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program


DECISION ID	150459	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Ammonia
Final Listing Decision:	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
Sources:	A Source Unknown
Expected TMDL Completion Date:	2037
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the 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. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 29 of 92 samples exceeded the Ammonia water quality objective and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 150459, Ammonia	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

253272

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_Whittier Narrows Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and the results are as follows: 11 of the 35 samples exceeded the water quality threshold for Ammonia as N. Although a total of 36 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:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (739917).

Temporal Representation:

Data for this waterbody was collected over the date range 2015-02-04 to 2020-07-01

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 150459, Ammonia	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

253315

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and the results are as follows: 18 of the 62 samples exceeded the water quality threshold for Ammonia as N. Although a total of 63 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:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (742412).

Temporal Representation:

Data for this waterbody was collected over the date range 2011-06-06 to 2020-07-01

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 150459, Ammonia	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

87955

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Zero out of 49 30-day averages exceeded the objective for ammonia. Only samples during the months when early life stages were absent were assessed. A calendar month was considered as a 30-day averaging period.

Data Reference:

Data for Various Pollutants in Various Water Bodies in Sanitation Districts of Los Angeles County, 2005-2010.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Los Angeles Regional Water Quality Control Plan 30-day site specific objective for total ammonia as nitrogen is a function of pH, temperature, and the presence of early life stages. The site specific objective for San Gabriel River Reaches 2 and 3 (Confluence with San Jose Creek to Firestone Blvd.) has early life stages absent from October 1st to March 31st.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected at monitoring stations Whittier Narrows/San Jose Creek R11 (SG-R11), Whittier Narrows/San Jose Creek R10 (SG-R10), and Whittier Narrows RA (WN-RA).

Temporal Representation:

Samples were collected from June 2005 to October 2009. Only samples during the months when early life stages were absent were assessed.

Environmental Conditions:

QAPP Information:

Samples were collected as part of an NPDES permit requirement. Receiving water data collected to represent the water body as a whole. No QAPP was submitted but an unsigned field manual was.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 150459, Ammonia	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

87954

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Zero out of 53 30-day averages exceeded the objective for ammonia. Only samples during the months when early life stages were present were assessed. A calendar month was considered as a 30-day averaging period.

Data Reference:

Data for Various Pollutants in Various Water Bodies in Sanitation Districts of Los Angeles County, 2005-2010.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected at monitoring stations Whittier Narrows/San Jose Creek R11 (SG-R11), Whittier Narrows/San Jose Creek R10 (SG-R10), and Whittier Narrows RA (WN-RA).

Temporal Representation:

Samples were collected from June 2005 to October 2009. Only samples during the months when early life stages were present were assessed.

Environmental Conditions:

QAPP Information:

Samples were collected as part of an NPDES permit requirement. Receiving water data collected to represent the water body as a whole. No QAPP was submitted but an unsigned field manual was.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 150459, Ammonia	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

2566

Pollutant:

Ammonia as Nitrogen

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Based on 30-day average concentrations of ammonia, one sample out of 18 total samples exceed the ammonia objective. Ambient measurements of pH and temperature (30-day averages) were used to calculate the water quality objective. (SWRCB, 2003).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: In order to protect aquatic life, ammonia concentrations in inland surface waters characteristic of freshwater shall not exceed the values calculated for the appropriate instream conditions [both pH and temperature] shown in Tables 3-1 to 3-3 [in the Basin Plan] (per U.S. EPA's most recent criteria guidance document, '1999 Update of Ambient Water Quality Criteria for Ammonia').

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Three stations.

Temporal Representation:

Samples were collected from June 2003 through November 2004.

Environmental Conditions:

QAPP Information:

NPDES quality assurance.

QAPP Information Reference(s):


DECISION ID	138667	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Chlorine
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Sources:	A Source Unknown
Expected TMDL Completion Date:	2037
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. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 8 of 8 samples exceed the criteria and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138667, Chlorine	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

253631

Pollutant:

Chlorine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and the results are as follows: 4 of the 4 samples exceeded the water quality threshold for Chlorine, Total Residual. Although a total of 137 samples were collected, 133 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:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region states that: Chlorine residual shall not be present in surface water any concentration that causes impairment of beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (742412).

Temporal Representation:

Data for this waterbody was collected over the date range 2011-06-06 to 2020-06-11

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 138667, Chlorine	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

253642

Pollutant:

Chlorine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_Whittier Narrows Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and the results are as follows: 4 of the 4 samples exceeded the water quality threshold for Chlorine, Total Residual. Although a total of 116 samples were collected, 112 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:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region states that: Chlorine residual shall not be present in surface water any concentration that causes impairment of beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (739917).

Temporal Representation:

Data for this waterbody was collected over the date range 2011-06-06 to 2020-06-11

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138667, Chlorine	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

253935

Pollutant:

Chlorine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_Whittier Narrows Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Chlorine, Total Residual. Although a total of 54 samples were collected, 54 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:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region states that: Chlorine residual shall not be present in surface water any concentration that causes impairment of beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-06-06 to 2019-02-18

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program


DECISION ID	138700	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Temperature, water
Final Listing Decision:	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
Sources:	A Source Unknown
Expected TMDL Completion Date:	2037
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. Temperature is a fractionless pollutant and the fractions "none" and "not recorded" are equivalent. The individual Lines of Evidence have been added together and compared to Table 3.2. 87 of 490 samples exceeded the objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 87 of 490 samples exceeded the objective and this exceeds the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 138700, Temperature, water	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

87965

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

141

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Numeric data generated from 141 averages of temperature had 19 exceedences.

Data Reference:

Data for Various Pollutants in Various Water Bodies in Sanitation Districts of Los Angeles County, 2005-2010.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

At no time shall warm freshwater habitat-designated waters be raised above 80 degrees Fahrenheit as a result of waste discharges.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from the SJC-R10, SJC/WN-R11, and WN-RA stations.

Temporal Representation:

Samples were collected approximately once a month from July 2005 to November 2009.

Environmental Conditions:

QAPP Information:

NPDES quality assurance.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138700, Temperature, water	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255836

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region (page 3-45) states that: For waters designated WARM, water temperature shall not be altered by more than 5 °F above the natural temperature. At no time shall these WARM-designated waters be raised above 80 °F as a result of waste discharges.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739918 (RSW-002).

Temporal Representation:

The samples were collected between the dates of 2011-06-06 and 2020-09-09

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 138700, Temperature, water	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255837

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

138

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_San Jose Creek Water Reclamation Plant data for San Gabriel River Reach 3 (Whittier Narrows to Ramona) to determine beneficial use support and results are as follows: 27 of 138 samples exceeded the water quality threshold for Temperature.

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 742412 (RSW-004).

Temporal Representation:

The samples were collected between the dates of 2011-06-06 and 2020-07-01

Environmental Conditions:

QAPP Information:

Los Angeles County Sanitation Districts. 2020. Los Angeles County Sanitation Districts Receiving Water Monitoring Program.

QAPP Information Reference(s):

Los Angeles County Sanitation Districts Receiving Water Monitoring Program

Line of Evidence (LOE) for Decision ID 138700, Temperature, water	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

255963

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

138

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Integrated Water Quality System (CIWQS) assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 739917 (RSW-001).

Temporal Representation:

The samples were collected between the dates of 2011-06-06 and 2020-07-01

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program


DECISION ID	68260	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Toxicity
Final Listing Decision:	Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Delist from 303(d) list (TMDL required list)(2016)
Revision Status	Original
Reason for Delisting:	Other
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 4.6 of the Listing Policy. Under section 4.6 a single line of evidence are necessary to assess listing status. 2 lines of evidence are available in the administrative record to assess pollutant. 2 of the 38 samples exceeded the GUIDELINE. 1 of the 75 sample exceeded the GUIDELINE. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for removing this water segment-pollutant combination from 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. 2 of 38 samples exceeded the GUIDELINE and this does not exceed the allowable frequency listed in Table 4.1 of the Listing Policy. 1 of the 75 samples exceeded the guideline, however, the control data was not provided, indicating poor quality assurance. 4. Pursuant to section 4.11 of the Listing Policy, no additional data

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be removed from the section 303(d) list because applicable water quality standards for the pollutant 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.

Line of Evidence (LOE) for Decision ID 68260, Toxicity	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

2565

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Two of 38 samples showed evidence of statistically significant toxicity. Ceriodaphnia dubia, Pimephales promelas, and Pseudokirchneriella subcapitata were used as test species in these samples.

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Narrative Toxicity Basin Plan WQO is applicable to the protection of aquatic life BUs.

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

No observed effect concentration (NOEC) is the highest tested concentration of toxicant to which organisms are exposed in a full life-cycle or partial life-cycle (shot-term) test that causes no observable adverse effect on the test organisms. The guideline is used and recommended to determine the highest concentration of toxicant at which the values of the observed responses are not statistically significantly different from the control.

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

The NPDES water quality monitoring samples were collected from receiving water stations WN-RA and R11. The TMDL toxicity study conducted by U.S. EPA and the Districts collected samples from the San Gabriel River at Peck Road.

Temporal Representation:

The NPDES water quality monitoring was conducted from June 2003 through May 2004. The TMDL toxicity study conducted by U.S. EPA and the Districts was conducted from August 2003 through October 2003.

Environmental Conditions:

QAPP Information:

QA Info Missing

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 68260, Toxicity	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

87970

Pollutant:

Toxicity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Toxicity data was not reported with a control. For acute toxicity, there shall be no acute toxicity in ambient waters, including mixing zones. The acute toxicity objective for discharges dictates that the average survival in undiluted effluent for any three consecutive 96-hour static or continuous flow bioassay tests shall be at least 90%, with no single test having less than 70% survival when using an established USEPA, State Board, or other protocol authorized by the Regional Board. For chronic toxicity, as stated in the Basin Plan, ¿there shall be no chronic toxicity in ambient waters outside mixing zones. To determine compliance with this objective, critical life stage tests for at least three species with approved testing protocols shall be used to screen for the most sensitive species. The test species used for screening shall include a vertebrate, an invertebrate, and an aquatic plant. The most sensitive species shall then be used for routine monitoring. Typical endpoints for chronic toxicity tests include hatchability, gross morphological abnormalities, survival, growth, and reproduction.¿ However, there is no specific numeric target for chronic toxicity in the Basin Plan. In light of this, it may also be that the use of the monthly median of chronic toxicity to assess the chronic toxicity is appropriate since this method is used in recently adopted Los Angeles Region NPDES permits.

1of 41 fathead minnow chronic-survival and 0of the 41 chronic-growth tests were less than 100 (these were grouped as 1 of 41 exceedances). The cerodaphnia chronic-survival and chronic reproduction tests were reported at none of fourteen at less than 100 (0 of 14 exceedances). 0 of the 20 acute tests on the fathead minnow were at less than 100% survival but greater than 90% (0 of 20 exceedances).

Data Reference:

Data for Various Pollutants in Various Water Bodies in Sanitation Districts of Los Angeles County, 2005-2010.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Toxic pollutants shall not be present at levels that will bioaccumulate in aquatic life to levels which are harmful to aquatic life or human health. 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.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Statistically significant difference from control using a t-test or other valid statistical tests.

Guideline Reference:

Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013

Spatial Representation:

Samples were collected from location SG sublocation R10 & R11 and WN sublocation RA.

Temporal Representation:

Samples were collected quarterly from June 2006 through May of 2010.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):


DECISION ID	73943	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Indicator Bacteria
Final Listing Decision:	Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision:	Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)(2016)
Revision Status	Original
Sources:	A Source Unknown
TMDL Name:	San Gabriel River Coliform (45)
TMDL Project Code:	391
Date TMDL Approved by USEPA:	06/14/2016
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for removal from the CWA section 303(d) List under section 4.3 of the Listing Policy. Under section 4.3 a single line of evidence is necessary to assess listing status. 2 lines of evidence are available in the administrative record to assess this pollutant. However only the E.Coli line of evidence is applicable due to a change in water quality objectives. 30 of 88 samples exceeded the OBJECTIVE. 14 of 37 samples exceeded the OBJECTIVE. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from 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. 44 of 125 samples exceeded the E. coli OBJECTIVE and this exceeds the allowable frequency listed in Table 4.2 of the Listing Policy. 4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met. There is sufficient justification to place this waterbody/pollutant in the Being Addressed portion of the CWA 303(d) List because a TMDL has been completed and approved by USEPA, and is expected to result in attainment of the standard. This conclusion is based on the staff findings that: 1. The San Gabriel River Bacteria TMDL was approved by USEPA on 06/14/2016.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are 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.

Line of Evidence (LOE) for Decision ID 73943, Indicator Bacteria	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

25354

Pollutant:

Indicator Bacteria

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

268

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

96 of 268 samples exceeded the Basin Plan single sample water quality objectives for indicator bacteria in fresh water and 29 of 53 samples exceeded the Basin Plan geometric mean water quality objective. Water quality samples were taken and analyzed for indicator bacteria in accordance with the Sanitation Districts of Los Angeles County permit monitoring and testing parameters.

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Basin Plan bacteria objectives state that to protect water contact recreation in fresh waters individual samples shall not exceed the following limits: fecal coliform density shall not exceed 400/100 ml; and E. coli density shall not exceed 235/100 ml. The bacteria objectives also establish that the geometric means of individual samples shall not exceed the following limits: the fecal coliform density shall not exceed 200/100 ml; and the E. coli density shall not exceed 126/100 ml, as a geometric mean. The bacteria objectives are found in Attachment A of Regional Board Resolution No. 2001-018.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The Sanitation Districts of Los Angeles County conducted sampling in San Gabriel Reach 3 in the following receiving water monitoring stations: station R10 located upstream of San Jose Creek confluence (Lat: N34° 02¿ 22.5¿¿ Long: W118° 01¿ 29¿¿) and station R11 located before the confluence with Zone 1 Ditch, upstream of Discharge points 001 and 002 of the Whittier Narrows Water Reclamatin Plant.

Temporal Representation:

Grab samples were taken and analyzed on monthly basis from August 2004 to February 2007.

Environmental Conditions:

QAPP Information:

Data was collected in compliance with the sampling and monitoring procedures detailed in Sanitation Districts of Los Angeles County (NPDES No. CA0053911) Monitoring and Reporting Program.

QAPP Information Reference(s):

San Jose Creek Water Reclamation Plant Monitoring and Reporting Program for NPDES No. CA0053911 (County Sanitation Districts of Los Angeles County)

Line of Evidence (LOE) for Decision ID 73943, Indicator Bacteria	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

87857

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Thirty of the 88 samples exceeded the E. coli objective.

Data Reference:

Data for Various Pollutants in Various Water Bodies in Sanitation Districts of Los Angeles County, 2005-2010.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The E. coli density shall not exceed 235/100 ml. (Water Quality Control Plan for the Los Angeles Region).

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

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

Spatial Representation:

The samples were collected at San Jose Creek Station RSW-004 (Station R-11 and R-10) and Whittier Narrows Station RSW-002 (Station R-A).

Temporal Representation:

The samples were collected weekly from June 2005 to December 2006 and once a month from January 2007 to May 2010.

Environmental Conditions:

QAPP Information:

The samples were collected under the San Jose Creek Laboratory sample collection procedures. Dec 28, 2010.

QAPP Information Reference(s):


DECISION ID	98421	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

Pollutant:	Endosulfan
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence are necessary to assess listing status. 1 line of evidence is available in the administrative record to assess this pollutant. 0 of 2 samples exceeded the CRITERIA. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 0 of 2 samples exceeded the CRITERIA 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.

Line of Evidence (LOE) for Decision ID 98421, Endosulfan	Region 4
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

LOE ID:

87855

Pollutant:

Endosulfan

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

None of the two samples exceeded the water quality criteria/objective.

Data Reference:

Data for Various Pollutants in Various Water Bodies in Sanitation Districts of Los Angeles County, 2005-2010.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Region 4 Basin Plan objective is "No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses."

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The California Toxic Rule criteria fresh aquatic life protection continuous concentration (4-day average)is 0.056 ug/L. (THIS CRITERIA USED IS FOR ENDOSULFAN I)

Guideline Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Spatial Representation:

A total of two samples were collected at two locations, SGR_SJC_R-11 and SGR_WN_R-A. One sample was from SGR_SJC_R-11 and one sample was from SGR_WN_R-A. Location Description:SGR_SJC_R-11 is San Jose Creek Station RSW-004 (Station R-11). SGR_WN_R-A is Whittier Narrows Station RSW-002 (Station R-A)

Temporal Representation:

From both locations, the two water samples were collected in 2/16/2010.

Environmental Conditions:

There was no special environmental conditions reported.

QAPP Information:

An excel spreadsheet of laboratory information called "LIMS" which gave reporting limits for each analyte evaluated accompanied each data package.

QAPP Information Reference(s):