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

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

QA Info Missing

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 150444, Ammonia	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

86019

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

13 out of 51 monthly averages exceeded the site specific basin plan objective for total ammonia as nitrogen. All exceedences occurred 2007 and prior.

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

he Los Angeles Regional Water Quality Control Plan objective for ammonia is a function of pH, temperature, and the presence of early life stages. Site specific objectives for this waterbody are based upon the presence of early life stages and found in Table 3-4. "Site-Specific 30-day Average Objectives for Ammonia by Waterbody Reach." Site specific objectives are applied as if early life stages are absent (dates ranging October 1 to March 31).

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected in three locations: LAG R4, LAG R5, and LAG R7.

Temporal Representation:

Samples were collected weekly from 07/2005 through 06/2010. Only samples collected from the months of October 1 to March 31 have been included.

Environmental Conditions:

QAPP Information:

All samples were collected by the Environmental Monitoring Division of the City of Los Angeles using a quality assurance program for all laboratory analysis. These laboratories are individually certified by the Environmental Laboratory Accreditation Program (ELAP) of the California Department of Health Services.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 150444, Ammonia	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

85894

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

20 out of 60 monthly averages exceeded the site specific basin plan objective for total ammonia as nitrogen. All the exceedences were 2007 and prior.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Los Angeles Regional Water Quality Control Plan objective for ammonia is a function of pH, temperature, and the presence of early life stages. Site specific objectives for this waterbody are based upon the presence of early life stages and found in Table 3-4. "Site-Specific 30-day Average Objectives for Ammonia by Waterbody Reach." Site specific objectives are applied as if early life stages are present (dates ranging April 1 to September 30).

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected in three locations: LAG R4, LAG R5, and LAG R7.

Temporal Representation:

Samples were collected weekly from 07/2005 through 06/2010. Only samples collected from the months of April 1 to September 30 have been included.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 150444, Ammonia	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253294

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N.

Data Reference:

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 site specific objective for Los Angeles river Reach 3, ELS present.

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: 829991 (RSW-654(a)).

Temporal Representation:

The samples were collected between the dates of 2017-04-04 and 2017-04-25, when early life stages are presumed to be present.

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 150444, Ammonia	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253599

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 20 samples exceeded the water quality threshold for Ammonia 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:

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: 833667 (RSW-LAGT650).

Temporal Representation:

The samples were collected between the dates of 2017-05-02 and 2020-09-29. Only samples collected between April 1 and September 30 of each year were considered for this LOE, using the site specific objective for early life stages present.

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 150444, Ammonia	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253598

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 23 samples exceeded the water quality threshold for Ammonia 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:

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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

The samples were collected between the dates of 2017-05-5 and 2020-09-29. Only samples collected between April 1 and September 30 of each year, when early life stages are presumed to be present, were used in this line of evidence.

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 150444, Ammonia	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253597

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 21 samples exceeded the water quality threshold for Ammonia 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 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 site specific objective for ammonia in the Los Angeles River Reach 3, with early life stages present.

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: 770470 (RSW-654).

Temporal Representation:

The samples were collected between the dates of 2012-04-03 and 2015-09-29. Only samples collected between April 1 and September 30 of each year, when early life stages are presumed to be present, were used in this line of evidence.

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 150444, Ammonia	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253601

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 1 of 21 samples exceeded the water quality threshold for Ammonia as N when early life stages were present.

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 site specific objective for Los Angeles River Reach 3, early life stages present.

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: 770468 (RSW-650).

Temporal Representation:

The samples were collected between the dates of 2012-04-03 and 2017-04-25. Only samples collected between April 1 and September 30 of each year, when early life stages are presumed to be present, were used in this line of evidence.

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 150444, Ammonia	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

315757

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 17 samples exceeded the water quality threshold for Ammonia 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:

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: 833667 (RSW-LAGT650).

Temporal Representation:

The samples were collected between the dates of 2017-10-03 and 2020-10-13. Only samples collected between October 1 and March 31 of each year were considered for this LOE, using the site specific objective for early life stages absent.

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 150444, Ammonia	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

315758

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 26 samples exceeded the water quality threshold for Ammonia as N when early life stages were absent.

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 site specific objective for Los Angeles River Reach 3, early life stages absent.

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: 770468 (RSW-650).

Temporal Representation:

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	150304	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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:	List on 303(d) list (being addressed by USEPA approved TMDL)(2018)
Revision Status	Revised
Sources:	A Source Unknown
TMDL Name:	Los Angeles River Pathogens (15)
TMDL Project Code:	238
Date TMDL Approved by USEPA:	03/23/2012
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for removal on the CWA section 303(d) List under sections 2.2 and sections 4.3 and 4.11 of the Listing Policy. Under section 4.3 of the Policy, a minimum of one line of evidence is needed to assess listing status. Two lines of evidence are available in the administrative record to assess this waterbody-pollutant combination. Because a statistically sufficient number of geomean samples were not available, attainment of the bacteria objective was determined based only on the STV per the situation-specific weight of evidence approach outlined in Sections 4.11 of the Listing Policy. 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. There is sufficient justification to place it in the Being Addressed portion of the CWA 303(d) List because a TMDL has been completed and approved by RWQCB and USEPA, and is expected to result in attainment of the standard. 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. 19 of 37 samples exceeded the statistical threshold value for E. coli and these exceed the allowable frequency listed in Table 4.2 of the Listing Policy. 4. The Los Angeles River Bacteria TMDL was approved by USEPA on 03/23/2012. 5. Pursuant to section 4.11 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 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 150304, Indicator Bacteria	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

302978

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

STV

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed LA County MS4 data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the Statistical Threshold Value (STV) water quality threshold for E. coli. The STV is based on a 10% exceedance rate that is calculated monthly.

Data Reference:

WQ data from the MS4 database assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The bacteria water quality objective to protect the REC-1 beneficial use where the salinity is less than 1 parts per thousand 95 percent or more of the time applies a statistical threshold value to E. coli of 320 cfu/100 mL, not to be exceeded by more than 10 percent of samples within a calendar month (ISWEBE 2018).

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s), station(s): LAR_03_ZOO (Los Angeles River (Zoo Dr)).

Temporal Representation:

The samples were collected between the days of 2015-12-29 and 2015-12-29 .

Environmental Conditions:

QAPP Information:

Municipal Separate Storm Sewer System (MS4)

QAPP Information Reference(s):

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 2010

Line of Evidence (LOE) for Decision ID 150304, Indicator Bacteria	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

86005

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

330

Number of Exceedances:

202

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Two hundred and two of the the 330 samples exceeded the E. coli objective.

Data Reference:

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 Los Angeles River R4, R5 and R7.

Temporal Representation:

The samples were collected once a week from 2006 to May 2010.

Environmental Conditions:

QAPP Information:

The quality assurance manual for the Environmental Monitoring Division Bureau of Sanitation, Department of Public Works, City of Los Angeles was provided. Los Angeles-Glendale Water Reclamation Plant NPDES permit no. CA0053953

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 150304, Indicator Bacteria	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

86006

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

247

Number of Exceedances:

237

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Two hundred and thirty-seven of the the 247 geometric means exceeded the E. coli objective.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The E. coli density shall not exceed 126/100 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 Los Angeles River R4, R5 and R7.

Temporal Representation:

The samples were collected once a week from 2006 to May 2010.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 150304, Indicator Bacteria	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

303193

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

STV

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed LA County MS4 data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and the results are as follows: 19 of the 36 samples exceeded the Statistical Threshold Value (STV) water quality threshold for E. coli. The STV is based on a 10% exceedance rate that is calculated monthly.

Data Reference:

WQ data from the MS4 database assembled for the 2024 Integrated Report in Region 4.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s), station(s): LAR_03_FIG (Los Angeles River (Figueroa St)).

Temporal Representation:

The samples were collected between the days of 2015-11-18 and 2019-12-18 .

Environmental Conditions:

QAPP Information:

Municipal Separate Storm Sewer System (MS4)

QAPP Information Reference(s):

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 2010


DECISION ID	138500	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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:	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 6 and 0 of 36 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 138500, 1,1,2-Trichloroethane	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

85990

Pollutant:

1,1,2-Trichloroethane

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:

All of the samples were below criteria.

Data Reference:

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:

The USEPA National Recomm. WQ criteria, chronic tox info, is 9,400 ug/L.

Guideline Reference:

Spatial Representation:

The River was sampled between Figueroa St. and Riverside Dr.

Temporal Representation:

One sample was collected in 2007, two samples was collected in 2008, two samples were collected in 2009, and one sample was collected in 2010.

Environmental Conditions:

There was no special environmental condition reported.

QAPP Information:

The samples were collected by the Environmental Monitoring Division of the City of Los Angeles using a quality assurance program for all laboratory analysis. These laboratories are individually certified by the Environmental Laboratory Accreditation Program (ELAP) of the California Department of Health Services.los angeles river

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138500, 1,1,2-Trichloroethane	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

256100

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 11 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: 770468 (RSW-650).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138500, 1,1,2-Trichloroethane	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

256300

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 7 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:

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: 833667 (RSW-LAGT650).

Temporal Representation:

The samples were collected between the dates of 2017-08-01 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138500, 1,1,2-Trichloroethane	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

256133

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 7 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:

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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

The samples were collected between the dates of 2017-08-01 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138500, 1,1,2-Trichloroethane	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

256290

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 2 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:

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: 829991 (RSW-654(a)).

Temporal Representation:

The samples were collected between the dates of 2016-12-06 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138500, 1,1,2-Trichloroethane	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

256103

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 9 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:

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: 770470 (RSW-654).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2015-08-04

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138475	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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 35 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 138475, 2,4-D (2,4-Dichlorophenoxy acetic acid)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254390

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Dichlorophenoxyacetic Acid, 2,4-.

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:

Los Angeles River Watershed-Wide Monitoring Program

Spatial Representation:

The samples were collected at 1 monitoring site: 833667 (RSW-LAGT650).

Temporal Representation:

The samples were collected between the dates of 2017-08-01 and 2020-09-09

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138475, 2,4-D (2,4-Dichlorophenoxy acetic acid)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254410

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Dichlorophenoxyacetic Acid, 2,4-.

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:

Los Angeles River Watershed-Wide Monitoring Program

Spatial Representation:

The samples were collected at 1 monitoring site: 829991 (RSW-654(a)).

Temporal Representation:

The samples were collected between the dates of 2016-12-06 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138475, 2,4-D (2,4-Dichlorophenoxy acetic acid)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

260543

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:

Water Board staff assessed Surface Water Monitoring Project data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Dichlorophenoxyacetic Acid, 2,4-.

Data Reference:

WQ data from the California Environmental Data Exchange Network 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:

STUDY 270: Ambient Surface Water and Mitigation Monitoring in Urban Areas in Southern

Spatial Representation:

The samples were collected at 1 monitoring site: Los Angeles 247 (Los Angeles River upper watershed).

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

Department of Pesticide Regulation Environmental Monitoring Branch Surface Water Protection Program. 2018. STUDY 270: Ambient Surface Water and Mitigation Monitoring in Urban Areas in Southern.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138475, 2,4-D (2,4-Dichlorophenoxy acetic acid)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254481

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Dichlorophenoxyacetic Acid, 2,4-.

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:

Los Angeles River Watershed-Wide Monitoring Program

Spatial Representation:

The samples were collected at 1 monitoring site: 833670 (RSW-LAGT654(a)).

Temporal Representation:

The samples were collected between the dates of 2017-08-01 and 2020-09-09

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138475, 2,4-D (2,4-Dichlorophenoxy acetic acid)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254478

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Dichlorophenoxyacetic Acid, 2,4-.

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:

Los Angeles River Watershed-Wide Monitoring Program

Spatial Representation:

The samples were collected at 1 monitoring site: 770470 (RSW-654).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2015-08-04

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138475, 2,4-D (2,4-Dichlorophenoxy acetic acid)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254437

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 10 samples exceeded the water quality threshold for Dichlorophenoxyacetic Acid, 2,4-.

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:

Los Angeles River Watershed-Wide Monitoring Program

Spatial Representation:

The samples were collected at 1 monitoring site: 770468 (RSW-650).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):


DECISION ID	138495	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	2-Methyl-4-chlorophenoxyacetic acid (MCPA):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:	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 138495, 2-Methyl-4-chlorophenoxyacetic acid (MCPA):acetic acid	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

263215

Pollutant:

2-Methyl-4-chlorophenoxyacetic acid (MCPA):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 Environmental Data Exchange Network 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 2-methyl-4-chlorophenoxyacetic acid (MCPA):acetic acid is the USEPA Aquatic Life Benchmark of 20 ug/L for a vascular plant (acute) for MCPA EHE.

Guideline Reference:

STUDY 270: Ambient Surface Water and Mitigation Monitoring in Urban Areas in Southern

Spatial Representation:

The samples were collected at 1 monitoring site: Los Angeles 247 (Los Angeles River upper watershed).

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

Department of Pesticide Regulation Environmental Monitoring Branch Surface Water Protection Program. 2018. STUDY 270: Ambient Surface Water and Mitigation Monitoring in Urban Areas in Southern.

QAPP Information Reference(s):


DECISION ID	138497	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	Acrolein
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 138497, Acrolein	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253504

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Acrolein. 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:

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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-01 to 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138497, Acrolein	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253398

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: 833667 (RSW-LAGT650).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-01 to 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138497, Acrolein	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

85991

Pollutant:

Acrolein

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:

All of the samples were below criteria.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 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:

The USEPA National Recomm. WQ criteria, 4-day avg. is 3 ug/L.

Guideline Reference:

Spatial Representation:

The River was sampled between Figueroa St. and Riverside Dr.

Temporal Representation:

One sample was collected in 2007, two samples was collected in 2008, three samples were collected in 2009, and one sample was collected in 2010.

Environmental Conditions:

There was no special environmental condition reported.

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138497, Acrolein	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253355

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Acrolein. Although a total of 11 samples were collected, 11 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:

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: 770468 (RSW-650).

Temporal Representation:

Data for this waterbody were collected over the date range 2012-02-07 to 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138497, Acrolein	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253375

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Acrolein. Although a total of 9 samples were collected, 9 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:

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: 770470 (RSW-654).

Temporal Representation:

Data for this waterbody were collected over the date range 2012-02-07 to 2015-08-04

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138497, Acrolein	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253486

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Acrolein. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

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: 829991 (RSW-654(a)).

Temporal Representation:

Data for this waterbody were collected over the date range 2016-12-06 to 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138499	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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

Regional Board Conclusion:	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 34 samples exceed the guideline. 0 of 24 samples exceeded the guideline. 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 24 and 0 of 34 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:	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 138499, Aldrin	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253311

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Aldrin.

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: 770470 (RSW-654).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2015-08-04

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138499, Aldrin	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253358

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Aldrin.

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: 829991 (RSW-654(a)).

Temporal Representation:

The samples were collected between the dates of 2016-12-06 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138499, Aldrin	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253359

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Aldrin.

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: 833667 (RSW-LAGT650).

Temporal Representation:

The samples were collected between the dates of 2017-08-01 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138499, Aldrin	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

85992

Pollutant:

Aldrin

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:

All of the samples were below criteria.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 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:

The California Toxics Rule, instantaneous max. is 1.5 ug/L.

Guideline Reference:

Spatial Representation:

The River was sampled between Figueroa St. and Riverside Dr.

Temporal Representation:

One sample was collected in 2007, two samples was collected in 2008, three samples were collected in 2009, and one sample was collected in 2010.

Environmental Conditions:

There was no special environmental condition reported.

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138499, Aldrin	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253334

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Aldrin.

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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

The samples were collected between the dates of 2017-08-01 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138499, Aldrin	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253378

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 10 samples exceeded the water quality threshold for Aldrin.

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: 770468 (RSW-650).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138450	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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 66 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 138450, Antimony	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253542

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: 770468 (RSW-650).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138450, Antimony	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253518

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 17 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: 770470 (RSW-654).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2016-11-15

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138450, Antimony	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253515

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 2 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: 829991 (RSW-654(a)).

Temporal Representation:

The samples were collected between the dates of 2016-12-06 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138450, Antimony	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253408

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 14 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: 833667 (RSW-LAGT650).

Temporal Representation:

The samples were collected between the dates of 2017-05-02 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138450, Antimony	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253561

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 14 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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

The samples were collected between the dates of 2017-05-02 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138451	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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 66 and 0 of 46 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 138451, Arsenic	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253349

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 14 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: 833667 (RSW-LAGT650).

Temporal Representation:

The samples were collected between the dates of 2017-05-02 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138451, Arsenic	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253438

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 2 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:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 829991 (RSW-654(a)).

Temporal Representation:

The samples were collected between the dates of 2016-12-06 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138451, Arsenic	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253458

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 17 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:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 770470 (RSW-654).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2016-11-15

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138451, Arsenic	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253476

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 14 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:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 833670 (RSW-LAGT654(a)).

Temporal Representation:

The samples were collected between the dates of 2017-05-02 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138451, Arsenic	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253546

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: 770468 (RSW-650).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138451, Arsenic	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

85993

Pollutant:

Arsenic

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:

None of the 46 samples exceeded the CTR.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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.

Objective/Criterion 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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The River was sampled between Figueroa St. and Riverside Dr.

Temporal Representation:

One sample was collected in 2007, two samples was collected in 2008, three samples were collected in 2009, and one sample was collected in 2010.

Environmental Conditions:

There was no special environmental condition reported.

QAPP Information:

QAPP Information Reference(s):


DECISION ID	138465	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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 138465, Azinphos-methyl (Guthion)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253285

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 8 samples were collected, 8 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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-01 to 2020-08-18

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138465, Azinphos-methyl (Guthion)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253306

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 8 samples were collected, 8 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: 833667 (RSW-LAGT650).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-01 to 2020-08-18

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138465, Azinphos-methyl (Guthion)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253264

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Azinphos Methyl. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the 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: 829991 (RSW-654(a)).

Temporal Representation:

Data for this waterbody were collected over the date range 2016-12-06 to 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138465, Azinphos-methyl (Guthion)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253265

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 9 samples were collected, 9 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: 770470 (RSW-654).

Temporal Representation:

Data for this waterbody were collected over the date range 2012-02-07 to 2015-11-03

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138465, Azinphos-methyl (Guthion)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253283

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 11 samples were collected, 11 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: 770468 (RSW-650).

Temporal Representation:

Data for this waterbody were collected over the date range 2012-02-07 to 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138452	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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 66 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 138452, Beryllium	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253926

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: 770468 (RSW-650).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138452, Beryllium	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253798

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 14 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: 833667 (RSW-LAGT650).

Temporal Representation:

The samples were collected between the dates of 2017-05-02 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138452, Beryllium	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253864

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 14 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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

The samples were collected between the dates of 2017-05-02 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138452, Beryllium	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253617

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 17 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: 770470 (RSW-654).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2016-11-15

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138452, Beryllium	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253882

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 2 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: 829991 (RSW-654(a)).

Temporal Representation:

The samples were collected between the dates of 2016-12-06 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138496	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	Bifenthrin
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 138496, Bifenthrin	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

257707

Pollutant:

Bifenthrin

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 Surface Water Monitoring Project data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bifenthrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

WQ data from the California Environmental Data Exchange Network 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 chronic criterion for bifenthrin is 0.1 ng/L (expressed as a 4-day average). If the freely dissolved concentrations of bifenthrin were reported or could be calculated then these values were used for this assessment. In the absence of freely dissolved concentrations, total concentrations were used.

Guideline Reference:

Water Quality Criteria Report for Bifenthrin

Spatial Representation:

The samples were collected at 1 monitoring site: Los Angeles 247 (Los Angeles River upper watershed).

Temporal Representation:

Data for this waterbody were collected over the date range 2015-06-03 to 2015-06-03

Environmental Conditions:

QAPP Information:

Department of Pesticide Regulation Environmental Monitoring Branch Surface Water Protection Program. 2018. STUDY 270: Ambient Surface Water and Mitigation Monitoring in Urban Areas in Southern.

QAPP Information Reference(s):

STUDY 270: Ambient Surface Water and Mitigation Monitoring in Urban Areas in Southern


DECISION ID	138453	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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. 2 lines of evidence are available in the administrative record to assess this pollutant. 0 of 66 samples exceeded the CRITERIA. 0 of 95 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 66 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:	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 138453, Cadmium	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253928

Pollutant:

Cadmium

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 2 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:

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: 829991 (RSW-654(a)).

Temporal Representation:

The samples were collected between the dates of 2016-12-06 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138453, Cadmium	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253603

Pollutant:

Cadmium

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 14 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: 833667 (RSW-LAGT650).

Temporal Representation:

The samples were collected between the dates of 2017-05-02 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138453, Cadmium	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

85995

Pollutant:

Cadmium

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:

All of the samples were below criteria. (Total recoverable cadmium was analyzed for.)

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 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:

The California Toxics Rule (USEPA), 4-day avg., dissolved, is 2.2 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:

The River was sampled between Figueroa St. and Riverside Dr.

Temporal Representation:

One sample was collected in 2007, two samples was collected in 2008, three samples were collected in 2009, and one sample was collected in 2010.

Environmental Conditions:

There was no special environmental condition reported.

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138453, Cadmium	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253929

Pollutant:

Cadmium

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 14 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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

The samples were collected between the dates of 2017-05-02 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138453, Cadmium	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253954

Pollutant:

Cadmium

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 17 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: 770470 (RSW-654).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2016-11-15

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138453, Cadmium	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253684

Pollutant:

Cadmium

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: 770468 (RSW-650).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138454	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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 138454, Chlordane	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255932

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

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: 829991 (RSW-654(a)).

Temporal Representation:

Data for this waterbody were collected over the date range 2016-12-06 to 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138454, Chlordane	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255994

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 8 samples were collected, 8 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: 770470 (RSW-654).

Temporal Representation:

Data for this waterbody were collected over the date range 2012-02-07 to 2015-08-04

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138454, Chlordane	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255933

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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: 770468 (RSW-650).

Temporal Representation:

Data for this waterbody were collected over the date range 2012-02-07 to 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138454, Chlordane	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

85996

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:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

All of the samples were below the reporting limit, which was above criteria. Therefore, non of the samples can be used with confidence.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 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:

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:

The River was sampled between Figueroa St. and Riverside Dr.

Temporal Representation:

One sample was collected in 2007, two samples was collected in 2008, three samples were collected in 2009, and one sample was collected in 2010.

Environmental Conditions:

There was no special environmental condition reported.

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138454, Chlordane	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255910

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the water quality threshold for Total Chlordane. Although a total of 7 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 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 (833667).

Temporal Representation:

Data for this waterbody was collected over the date range 2017-08-01 to 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138454, Chlordane	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255931

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:

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 (833670).

Temporal Representation:

Data for this waterbody was collected over the date range 2017-08-01 to 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138455	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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. 0 of 66 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:	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 138455, Chloride	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

243896

Pollutant:

Chloride

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 data from the Los Angeles-Glendale Wastewater Reclamation Plant to determine beneficial use support. The results are as follows: 0 out of 14 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 Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) of 190 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Station RSW-LAGT650 (34.1377, -118.27532), located in Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.).

Temporal Representation:

The water samples were taken between 5/2/2017 - 8/11/2020, per the monitoring requirements listed in the Los Angeles-Glendale Wastewater Reclamation Plant NPDES Permit monitoring and reporting program.

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the Los Angeles-Glendale Wastewater Reclamation Plant NDPES Permit quality assurance provisions for water quality monitoring.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138455, Chloride	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

243892

Pollutant:

Chloride

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 data from the Los Angeles-Glendale Wastewater Reclamation Plant to determine beneficial use support. The results are as follows: 0 out of 2 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 Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) of 190 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Station RSW-654(a) (34.13, -118.27314), located in Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.).

Temporal Representation:

The water samples were taken between 12/6/2016 - 2/16/2017, per the monitoring requirements listed in the Los Angeles-Glendale Wastewater Reclamation Plant NPDES Permit monitoring and reporting program.

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the Los Angeles-Glendale Wastewater Reclamation Plant NDPES Permit quality assurance provisions for water quality monitoring.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138455, Chloride	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

243883

Pollutant:

Chloride

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 data from the Los Angeles-Glendale Wastewater Reclamation Plant to determine beneficial use support. The results are as follows: 0 out of 17 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 Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) of 190 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Station RSW-654 (34.122833, -118.27045), located in Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.).

Temporal Representation:

The water samples were taken between 2/7/2012 - 11/15/2016, per the monitoring requirements listed in the Los Angeles-Glendale Wastewater Reclamation Plant NPDES Permit monitoring and reporting program.

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the Los Angeles-Glendale Wastewater Reclamation Plant NDPES Permit quality assurance provisions for water quality monitoring.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138455, Chloride	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

243873

Pollutant:

Chloride

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 data from the Los Angeles-Glendale Wastewater Reclamation Plant to determine beneficial use support. The results are as follows: 0 out of 19 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 Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) of 190 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Station RSW-650 (34.134833, -118.274533), located in Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.).

Temporal Representation:

The water samples were taken between 2/7/2012 - 2/16/2017, per the monitoring requirements listed in the Los Angeles-Glendale Wastewater Reclamation Plant NPDES Permit monitoring and reporting program.

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the Los Angeles-Glendale Wastewater Reclamation Plant NDPES Permit quality assurance provisions for water quality monitoring.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138455, Chloride	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

243905

Pollutant:

Chloride

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 list a site specific objective for Chloride in the Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) of 190 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Station RSW-LAGT654(a) (34.13, -118.27314), located in Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.).

Temporal Representation:

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the Los Angeles-Glendale Wastewater Reclamation Plant NDPES Permit quality assurance provisions for water quality monitoring.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138456	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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

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

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 138456, Chlorine	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253670

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 214 samples were collected, 214 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: 770468 (RSW-650).

Temporal Representation:

Data for this waterbody were collected over the date range 2012-02-07 to 2017-04-25

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138456, Chlorine	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253689

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 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 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: 829991 (RSW-654(a)).

Temporal Representation:

Data for this waterbody were collected over the date range 2016-12-06 to 2017-04-25

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138456, Chlorine	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253667

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 169 samples were collected, 169 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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-05-02 to 2020-10-13

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138456, Chlorine	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253650

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 169 samples were collected, 169 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: 833667 (RSW-LAGT650).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-05-02 to 2020-10-13

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138456, Chlorine	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253612

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 197 samples were collected, 197 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: 770470 (RSW-654).

Temporal Representation:

Data for this waterbody were collected over the date range 2012-02-07 to 2016-11-30

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138504	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	Chromium
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 66 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 138504, Chromium	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253613

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 2 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:

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: 829991 (RSW-654(a)).

Temporal Representation:

The samples were collected between the dates of 2016-12-06 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138504, Chromium	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254079

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 14 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: 833667 (RSW-LAGT650).

Temporal Representation:

The samples were collected between the dates of 2017-05-02 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138504, Chromium	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253636

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 14 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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

The samples were collected between the dates of 2017-05-02 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138504, Chromium	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253634

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:

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: 770468 (RSW-650).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138504, Chromium	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254075

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 17 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: 770470 (RSW-654).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2016-11-15

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138457	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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 66 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 138457, Chromium, hexavalent	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254082

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: 770468 (RSW-650).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138457, Chromium, hexavalent	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254062

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 14 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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

The samples were collected between the dates of 2017-05-02 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138457, Chromium, hexavalent	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254154

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 17 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: 770470 (RSW-654).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2016-11-15

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138457, Chromium, hexavalent	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254110

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 2 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: 829991 (RSW-654(a)).

Temporal Representation:

The samples were collected between the dates of 2016-12-06 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138457, Chromium, hexavalent	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254010

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 14 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: 833667 (RSW-LAGT650).

Temporal Representation:

The samples were collected between the dates of 2017-05-02 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138458	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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 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:	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 138458, Chromium, trivalent	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254197

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 2 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:

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: 829991 (RSW-654(a)).

Temporal Representation:

The samples were collected between the dates of 2016-12-06 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138458, Chromium, trivalent	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254242

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 17 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: 770470 (RSW-654).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2016-11-15

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138458, Chromium, trivalent	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254220

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 13 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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

The samples were collected between the dates of 2017-05-02 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138458, Chromium, trivalent	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254216

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 12 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: 833667 (RSW-LAGT650).

Temporal Representation:

The samples were collected between the dates of 2017-05-02 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138458, Chromium, trivalent	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254221

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: 770468 (RSW-650).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138459	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	Cyanide
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. 4 of 66 and 1 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:	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 138459, Cyanide	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254067

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 1 of 17 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: 770470 (RSW-654).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2016-11-15

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138459, Cyanide	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254092

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 1 of 2 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: 829991 (RSW-654(a)).

Temporal Representation:

The samples were collected between the dates of 2016-12-06 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138459, Cyanide	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254090

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 2 of 19 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: 770468 (RSW-650).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138459, Cyanide	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

85998

Pollutant:

Cyanide

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:

One of the ninty-five samples exceeded the evaluation guideline.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 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) for cyanide of 5.2 ug/L to protect aquatic life in freshwater.

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:

The River was sampled between Figueroa St. and Riverside Dr.

Temporal Representation:

One sample was collected in 2007, two samples was collected in 2008, three samples were collected in 2009, and one sample was collected in 2010.

Environmental Conditions:

There was no special environmental condition reported.

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138459, Cyanide	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254207

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 14 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: 833667 (RSW-LAGT650).

Temporal Representation:

The samples were collected between the dates of 2017-05-02 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138459, Cyanide	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254111

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 14 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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

The samples were collected between the dates of 2017-05-02 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138501	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	Cyfluthrin
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 138501, Cyfluthrin	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

259251

Pollutant:

Cyfluthrin

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 Surface Water Monitoring Project data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyfluthrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

WQ data from the California Environmental Data Exchange Network 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 chronic criterion for cyfluthrin is 0.2 ng/L (expressed as a 4-day average). If the freely dissolved concentrations of cyfluthrin were reported or could be calculated then these values were used for this assessment. In the absence of freely dissolved concentrations, total concentrations were used.

Guideline Reference:

Water Quality Criteria Report for Cyfluthrin

Spatial Representation:

The samples were collected at 1 monitoring site: Los Angeles 247 (Los Angeles River upper watershed).

Temporal Representation:

Data for this waterbody were collected over the date range 2015-06-03 to 2015-06-03

Environmental Conditions:

QAPP Information:

Department of Pesticide Regulation Environmental Monitoring Branch Surface Water Protection Program. 2018. STUDY 270: Ambient Surface Water and Mitigation Monitoring in Urban Areas in Southern.

QAPP Information Reference(s):

STUDY 270: Ambient Surface Water and Mitigation Monitoring in Urban Areas in Southern


DECISION ID	138503	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	Cyhalothrin, Lambda
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 138503, Cyhalothrin, Lambda	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

262587

Pollutant:

Cyhalothrin, Lambda

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 Surface Water Monitoring Project data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Lambda-cyhalothrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

WQ data from the California Environmental Data Exchange Network 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 chronic criterion for lambda-cyhalothrin is 0.3 ng/L (expressed as a 4-day average). If the freely dissolved concentrations of lambda-cyhalothrin were reported or could be calculated then these values were used for this assessment. In the absence of freely dissolved concentrations, total concentrations were used.

Guideline Reference:

Water Quality Criteria Report for Lambda-cyhalothrin

Spatial Representation:

The samples were collected at 1 monitoring site: Los Angeles 247 (Los Angeles River upper watershed).

Temporal Representation:

Data for this waterbody were collected over the date range 2015-06-03 to 2015-06-03

Environmental Conditions:

QAPP Information:

Department of Pesticide Regulation Environmental Monitoring Branch Surface Water Protection Program. 2018. STUDY 270: Ambient Surface Water and Mitigation Monitoring in Urban Areas in Southern.

QAPP Information Reference(s):

STUDY 270: Ambient Surface Water and Mitigation Monitoring in Urban Areas in Southern


DECISION ID	149695	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	DDT (Dichlorodiphenyltrichloroethane)
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 sections 3.1 and 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. 1 line of evidence is available in the administrative record to assess this pollutant. 0 of 23 samples exceed the guideline. 0 of 0 samples exceed the criteria. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for not 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 23 samples exceed the guideline for DDT in sediment and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. There is not an associated sediment toxicity data as required by Section 3.6 of the Listing Policy. 0 of 0 samples exceed the criteria for DDT in water and this is insufficient to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. 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 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 149695, DDT (Dichlorodiphenyltrichloroethane)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254261

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 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 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: 833667 (RSW-LAGT650).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-01 to 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 149695, DDT (Dichlorodiphenyltrichloroethane)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254189

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

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: 829991 (RSW-654(a)).

Temporal Representation:

Data for this waterbody were collected over the date range 2016-12-06 to 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 149695, DDT (Dichlorodiphenyltrichloroethane)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254213

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 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 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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-01 to 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 149695, DDT (Dichlorodiphenyltrichloroethane)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254192

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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: 770468 (RSW-650).

Temporal Representation:

Data for this waterbody were collected over the date range 2012-02-07 to 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 149695, DDT (Dichlorodiphenyltrichloroethane)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254121

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 8 samples were collected, 8 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: 770470 (RSW-654).

Temporal Representation:

Data for this waterbody were collected over the date range 2012-02-07 to 2015-08-04

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 149695, DDT (Dichlorodiphenyltrichloroethane)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

86001

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

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 twenty three samples exceeded the evaluation guideline.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for sum of DDT is 62.9 ug/Kg dry weight.

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Sediment samples were collected at station LA River R4, LA River R5 and LA River R7.

Temporal Representation:

Samples were collected in 2006 on February 7 and August 2, and in 2007 on February 7.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):


DECISION ID	138502	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	Deltamethrin
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 138502, Deltamethrin	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

260250

Pollutant:

Deltamethrin

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 Surface Water Monitoring Project data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Deltamethrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

WQ data from the California Environmental Data Exchange Network 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 deltamethrin is the USEPA Aquatic Life Benchmark of 0.000026 ug/L for an invertebrate (chronic).

Guideline Reference:

STUDY 270: Ambient Surface Water and Mitigation Monitoring in Urban Areas in Southern

Spatial Representation:

The samples were collected at 1 monitoring site: Los Angeles 247 (Los Angeles River upper watershed).

Temporal Representation:

Data for this waterbody were collected over the date range 2015-06-03 to 2015-06-03

Environmental Conditions:

QAPP Information:

Department of Pesticide Regulation Environmental Monitoring Branch Surface Water Protection Program. 2018. STUDY 270: Ambient Surface Water and Mitigation Monitoring in Urban Areas in Southern.

QAPP Information Reference(s):


DECISION ID	138505	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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 138505, Demeton	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254003

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and the results are as follows: 0 of the 7 samples exceeded the water quality threshold for Demeton, Total. Although a total of 11 samples were collected, 4 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 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 (770468).

Temporal Representation:

Data for this waterbody was collected over the date range 2012-02-07 to 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138505, Demeton	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253959

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Demeton, Total. Although a total of 8 samples were collected, 8 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 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: 833667 (RSW-LAGT650).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-01 to 2020-08-18

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138505, Demeton	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254300

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Demeton, Total. Although a total of 8 samples were collected, 8 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 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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-01 to 2020-08-18

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138505, Demeton	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254301

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Demeton, Total. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

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: 829991 (RSW-654(a)).

Temporal Representation:

Data for this waterbody were collected over the date range 2016-12-06 to 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138505, Demeton	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253960

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and the results are as follows: 0 of the 7 samples exceeded the water quality threshold for Demeton, Total. Although a total of 9 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

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 (770470).

Temporal Representation:

Data for this waterbody was collected over the date range 2012-02-07 to 2015-11-03

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138461	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	Diazinon
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 36 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 138461, Diazinon	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254585

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Diazinon. Although a total of 20 samples were collected, 20 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 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:

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: 833667 (RSW-LAGT650).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-05-02 to 2020-08-18

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138461, Diazinon	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254474

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Diazinon. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

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: 829991 (RSW-654(a)).

Temporal Representation:

Data for this waterbody were collected over the date range 2016-12-06 to 2017-03-15

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138461, Diazinon	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254563

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and the results are as follows: 0 of the 18 samples exceeded the water quality threshold for Diazinon. Although a total of 26 samples were collected, 8 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 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 (770468).

Temporal Representation:

Data for this waterbody was collected over the date range 2012-04-17 to 2017-03-15

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138461, Diazinon	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254561

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and the results are as follows: 0 of the 18 samples exceeded the water quality threshold for Diazinon. Although a total of 23 samples were collected, 5 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 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 (770470).

Temporal Representation:

Data for this waterbody was collected over the date range 2012-04-17 to 2015-11-24

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138461, Diazinon	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254539

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Diazinon. Although a total of 20 samples were collected, 20 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 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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-05-02 to 2020-08-18

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138493	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	Dicamba
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 138493, Dicamba	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

260495

Pollutant:

Dicamba

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 Environmental Data Exchange Network 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 dicamba is the USEPA Aquatic Life Benchmark of 61 ug/L for a nonvascular plant (acute) for Dicamba acid.

Guideline Reference:

STUDY 270: Ambient Surface Water and Mitigation Monitoring in Urban Areas in Southern

Spatial Representation:

The samples were collected at 1 monitoring site: Los Angeles 247 (Los Angeles River upper watershed).

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

Department of Pesticide Regulation Environmental Monitoring Branch Surface Water Protection Program. 2018. STUDY 270: Ambient Surface Water and Mitigation Monitoring in Urban Areas in Southern.

QAPP Information Reference(s):


DECISION ID	138462	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	Dieldrin
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 of 48 and 0 of 24 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 138462, Dieldrin	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254620

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Dieldrin.

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: 829991 (RSW-654(a)).

Temporal Representation:

The samples were collected between the dates of 2016-12-06 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138462, Dieldrin	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

86002

Pollutant:

Dieldrin

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:

All of the samples were below criteria.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 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:

The California Toxics Rule (USEPA), 4-day avg., is 0.056 ug/L.

Guideline Reference:

Spatial Representation:

The River was sampled between Figueroa St. and Riverside Dr.

Temporal Representation:

One sample was collected in 2007, two samples was collected in 2008, three samples were collected in 2009, and one sample was collected in 2010.

Environmental Conditions:

There was no special environmental condition reported.

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138462, Dieldrin	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254570

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 14 samples exceeded the water quality threshold for Dieldrin.

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: 833667 (RSW-LAGT650).

Temporal Representation:

The samples were collected between the dates of 2017-06-20 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138462, Dieldrin	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254692

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Dieldrin.

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: 770470 (RSW-654).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2015-08-04

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138462, Dieldrin	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254666

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 10 samples exceeded the water quality threshold for Dieldrin.

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: 770468 (RSW-650).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138462, Dieldrin	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254645

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 14 samples exceeded the water quality threshold for Dieldrin.

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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

The samples were collected between the dates of 2017-06-20 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138463	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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 34 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 138463, Endosulfan sulfate	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254678

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 10 samples exceeded the water quality threshold for Endosulfan 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 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: 770468 (RSW-650).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138463, Endosulfan sulfate	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254656

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Endosulfan 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 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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

The samples were collected between the dates of 2017-08-01 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138463, Endosulfan sulfate	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254632

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Endosulfan 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 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: 833667 (RSW-LAGT650).

Temporal Representation:

The samples were collected between the dates of 2017-08-01 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138463, Endosulfan sulfate	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254633

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Endosulfan 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 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: 829991 (RSW-654(a)).

Temporal Representation:

The samples were collected between the dates of 2016-12-06 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138463, Endosulfan sulfate	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254605

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Endosulfan 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 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: 770470 (RSW-654).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2015-08-04

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138464	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	Endrin
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. 2 lines of evidence areavailable in the administrative record to assess this pollutant. 0 of 23 samples exceeded the CRITERIA. 0 of 34 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 23 and 0 of 34 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 138464, Endrin	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254680

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Endrin.

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: 829991 (RSW-654(a)).

Temporal Representation:

The samples were collected between the dates of 2016-12-06 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138464, Endrin	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

86004

Pollutant:

Endrin

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 23 samples exceeded the water quality criteria/objective.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 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 Toxic Rule criteria fresh aquatic life protection continuous concentration (4-day average)is 0.036 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 23 samples were collected at sampling locations, LA RIVER R-4 (9 samples), LA River R-5 (5 samples) and LA River R-7 (9 samples).

Temporal Representation:

23 samples from 2006 - 2010 were collected. At LA RIVER R-4, two samples in 2006, two samples in 2007, two samples in 2008, two samples in 2009, and one sample in 2010 were collected. At LA River R-5, two samples in 2006, two samples in 2007, and one sample in 2008 were collected. LA River R-7 two samples in 2007, two samples in 2008, two samples in 2009, and one sample in 2010 were collected.

Environmental Conditions:

There was no special environmental conditions reported.

QAPP Information:

ENVIRONMENTAL MONITORING DIVISION (EMD) BUREAU OF ENVIRONMENTAL MONITORING DIVISION (EMD) BUREAU OF SANITATION DEPARTMENT OF PUBLIC WORKS CITY OF LOS ANGELES submitted QUALITY ASSURANCE MANUAL (QA) dated December 2009. The Quality Assurance Manual documents the QA Program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138464, Endrin	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254333

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Endrin.

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: 770470 (RSW-654).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2015-08-04

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138464, Endrin	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254335

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 10 samples exceeded the water quality threshold for Endrin.

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: 770468 (RSW-650).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138464, Endrin	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254765

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Endrin.

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: 833667 (RSW-LAGT650).

Temporal Representation:

The samples were collected between the dates of 2017-08-01 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138464, Endrin	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254766

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Endrin.

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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

The samples were collected between the dates of 2017-08-01 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138506	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	Esfenvalerate/Fenvalerate
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 138506, Esfenvalerate/Fenvalerate	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

261429

Pollutant:

Esfenvalerate/Fenvalerate

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 Surface Water Monitoring Project data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Esfenvalerate. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

WQ data from the California Environmental Data Exchange Network 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 chronic criterion for esfenvalerate is 0.3 ng/L (expressed as a 4-day average). If the freely dissolved concentrations of esfenvalerate were reported or could be calculated then these values were used for this assessment. In the absence of freely dissolved concentrations, total concentrations were used.

Guideline Reference:

Water Quality Criteria Report for Esfenvalerate

Spatial Representation:

The samples were collected at 1 monitoring site: Los Angeles 247 (Los Angeles River upper watershed).

Temporal Representation:

Data for this waterbody were collected over the date range 2015-06-03 to 2015-06-03

Environmental Conditions:

QAPP Information:

Department of Pesticide Regulation Environmental Monitoring Branch Surface Water Protection Program. 2018. STUDY 270: Ambient Surface Water and Mitigation Monitoring in Urban Areas in Southern.

QAPP Information Reference(s):

STUDY 270: Ambient Surface Water and Mitigation Monitoring in Urban Areas in Southern


DECISION ID	138492	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	Fipronil
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 138492, Fipronil	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

261806

Pollutant:

Fipronil

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 Surface Water Monitoring Project data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Fipronil.

Data Reference:

WQ data from the California Environmental Data Exchange Network 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:

UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the four-day average concentration of fipronil does not exceed 0.0032 ug/L (3.2 ng/L) in the water column more than once every three years on average (Bower, et al. 2017).

Guideline Reference:

Water and Sediment Quality Criteria Report for Fipronil. Phase III: Application of the pesticide water and sediment quality criteria methodologies. Department of Environmental Toxicology, University of California, Davis.

Spatial Representation:

The samples were collected at 1 monitoring site: Los Angeles 247 (Los Angeles River upper watershed).

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

Department of Pesticide Regulation Environmental Monitoring Branch Surface Water Protection Program. 2018. STUDY 270: Ambient Surface Water and Mitigation Monitoring in Urban Areas in Southern.

QAPP Information Reference(s):

STUDY 270: Ambient Surface Water and Mitigation Monitoring in Urban Areas in Southern


DECISION ID	138449	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	Fipronil Desulfinyl
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 138449, Fipronil Desulfinyl	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

261792

Pollutant:

Fipronil Desulfinyl

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 Environmental Data Exchange Network 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 fipronil degradate fipronil desulfinyl is the USEPA Aquatic Life Benchmark of 0.54 ug/L for a fish (chronic).

Guideline Reference:

STUDY 270: Ambient Surface Water and Mitigation Monitoring in Urban Areas in Southern

Spatial Representation:

The samples were collected at 1 monitoring site: Los Angeles 247 (Los Angeles River upper watershed).

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

Department of Pesticide Regulation Environmental Monitoring Branch Surface Water Protection Program. 2018. STUDY 270: Ambient Surface Water and Mitigation Monitoring in Urban Areas in Southern.

QAPP Information Reference(s):


DECISION ID	138507	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	Fipronil Sulfide
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 138507, Fipronil Sulfide	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

261891

Pollutant:

Fipronil Sulfide

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 Environmental Data Exchange Network 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 fipronil degradate fipronil sulfide is the USEPA Aquatic Life Benchmark of 0.83 ug/L for a fish (chronic).

Guideline Reference:

STUDY 270: Ambient Surface Water and Mitigation Monitoring in Urban Areas in Southern

Spatial Representation:

The samples were collected at 1 monitoring site: Los Angeles 247 (Los Angeles River upper watershed).

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

Department of Pesticide Regulation Environmental Monitoring Branch Surface Water Protection Program. 2018. STUDY 270: Ambient Surface Water and Mitigation Monitoring in Urban Areas in Southern.

QAPP Information Reference(s):


DECISION ID	138508	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	Fipronil Sulfone
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 138508, Fipronil Sulfone	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

261762

Pollutant:

Fipronil Sulfone

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 Environmental Data Exchange Network 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 fipronil degradate fipronil sulfone is the USEPA Aquatic Life Benchmark of 0.037 ug/L for an invertebrate (chronic).

Guideline Reference:

STUDY 270: Ambient Surface Water and Mitigation Monitoring in Urban Areas in Southern

Spatial Representation:

The samples were collected at 1 monitoring site: Los Angeles 247 (Los Angeles River upper watershed).

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

Department of Pesticide Regulation Environmental Monitoring Branch Surface Water Protection Program. 2018. STUDY 270: Ambient Surface Water and Mitigation Monitoring in Urban Areas in Southern.

QAPP Information Reference(s):


DECISION ID	138466	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	Heptachlor
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 138466, Heptachlor	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255007

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

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: 829991 (RSW-654(a)).

Temporal Representation:

Data for this waterbody were collected over the date range 2016-12-06 to 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138466, Heptachlor	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254921

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 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 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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-01 to 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138466, Heptachlor	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254709

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 8 samples were collected, 8 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: 770470 (RSW-654).

Temporal Representation:

Data for this waterbody were collected over the date range 2012-02-07 to 2015-08-04

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138466, Heptachlor	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254707

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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: 770468 (RSW-650).

Temporal Representation:

Data for this waterbody were collected over the date range 2012-02-07 to 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138466, Heptachlor	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

86007

Pollutant:

Heptachlor

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 from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 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:

A total of 23 samples were collected at sampling locations, LA RIVER R-4 (9 samples), LA River R-5 (5 samples) and LA River R-7 (9 samples).

Temporal Representation:

Environmental Conditions:

There was no special environmental conditions reported.

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138466, Heptachlor	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254734

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 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 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: 833667 (RSW-LAGT650).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-01 to 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138467	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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 138467, Heptachlor epoxide	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254928

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 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 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: 833667 (RSW-LAGT650).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-01 to 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138467, Heptachlor epoxide	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254774

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 8 samples were collected, 8 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: 770470 (RSW-654).

Temporal Representation:

Data for this waterbody were collected over the date range 2012-02-07 to 2015-08-04

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138467, Heptachlor epoxide	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254882

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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: 770468 (RSW-650).

Temporal Representation:

Data for this waterbody were collected over the date range 2012-02-07 to 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138467, Heptachlor epoxide	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254860

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

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: 829991 (RSW-654(a)).

Temporal Representation:

Data for this waterbody were collected over the date range 2016-12-06 to 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138467, Heptachlor epoxide	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

86009

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:

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 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:

A total of 23 samples were collected at sampling locations, LA RIVER R-4 (9 samples), LA River R-5 (5 samples) and LA River R-7 (9 samples).

Temporal Representation:

Environmental Conditions:

There was no special environmental conditions reported.

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138467, Heptachlor epoxide	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254820

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 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 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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-01 to 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138494	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	Imidacloprid
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 138494, Imidacloprid	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

262387

Pollutant:

Imidacloprid

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 Surface Water Monitoring Project data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Imidacloprid.

Data Reference:

WQ data from the California Environmental Data Exchange Network 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:

UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the 4-day average concentration of imidacloprid does not exceed 0.016 ug/L.

Guideline Reference:

Water Quality Criteria Report for Imidacloprid Phase III: Application of the pesticide water quality criteria methodology. Department of Environmental Toxicology. University of California, Davis

Spatial Representation:

The samples were collected at 1 monitoring site: Los Angeles 247 (Los Angeles River upper watershed).

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

Department of Pesticide Regulation Environmental Monitoring Branch Surface Water Protection Program. 2018. STUDY 270: Ambient Surface Water and Mitigation Monitoring in Urban Areas in Southern.

QAPP Information Reference(s):

STUDY 270: Ambient Surface Water and Mitigation Monitoring in Urban Areas in Southern


DECISION ID	138468	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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 34 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 138468, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254857

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for HCH, gamma-.

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: 833667 (RSW-LAGT650).

Temporal Representation:

The samples were collected between the dates of 2017-08-01 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138468, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254855

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for HCH, gamma-.

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: 829991 (RSW-654(a)).

Temporal Representation:

The samples were collected between the dates of 2016-12-06 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138468, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254768

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for HCH, gamma-.

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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

The samples were collected between the dates of 2017-08-01 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138468, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254817

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for HCH, gamma-.

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: 770470 (RSW-654).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2015-08-04

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138468, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254852

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 10 samples exceeded the water quality threshold for HCH, gamma-.

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: 770468 (RSW-650).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138469	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	Malathion
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 138469, Malathion	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255261

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 11 samples were collected, 11 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: 770468 (RSW-650).

Temporal Representation:

Data for this waterbody were collected over the date range 2012-02-07 to 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138469, Malathion	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255223

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 9 samples were collected, 9 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: 770470 (RSW-654).

Temporal Representation:

Data for this waterbody were collected over the date range 2012-02-07 to 2015-11-03

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138469, Malathion	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255262

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 8 samples were collected, 8 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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-01 to 2020-08-18

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138469, Malathion	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255180

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

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: 829991 (RSW-654(a)).

Temporal Representation:

Data for this waterbody were collected over the date range 2016-12-06 to 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138469, Malathion	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255181

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 8 samples were collected, 8 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: 833667 (RSW-LAGT650).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-01 to 2020-08-18

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	150108	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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. 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 66 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:	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 150108, Mercury	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255309

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 14 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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

The samples were collected between the dates of 2017-05-02 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 150108, Mercury	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

86011

Pollutant:

Mercury

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:

None of the 95 samples exceeded the evaluation guideline.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 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:

The River was sampled between Figueroa St. and Riverside Dr.

Temporal Representation:

One sample was collected in 2007, two samples was collected in 2008, three samples were collected in 2009, and one sample was collected in 2010.

Environmental Conditions:

There was no special environmental condition reported.

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 150108, Mercury	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255331

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 2 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: 829991 (RSW-654(a)).

Temporal Representation:

The samples were collected between the dates of 2016-12-06 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 150108, Mercury	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255122

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 14 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: 833667 (RSW-LAGT650).

Temporal Representation:

The samples were collected between the dates of 2017-05-02 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 150108, Mercury	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255249

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: 770468 (RSW-650).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 150108, Mercury	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255096

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 17 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: 770470 (RSW-654).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2016-11-15

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138470	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	Methoxychlor
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. 2 lines of evidence are available in the administrative record to assess this pollutant. 0 of 23 samples exceeded the CRITERIA. 0 of 34 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 23 and 0 of 34 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 138470, Methoxychlor	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255101

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 10 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: 770468 (RSW-650).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138470, Methoxychlor	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255105

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 2 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: 829991 (RSW-654(a)).

Temporal Representation:

The samples were collected between the dates of 2016-12-06 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138470, Methoxychlor	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255357

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 7 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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

The samples were collected between the dates of 2017-08-01 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138470, Methoxychlor	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255359

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 7 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: 833667 (RSW-LAGT650).

Temporal Representation:

The samples were collected between the dates of 2017-08-01 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138470, Methoxychlor	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255041

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 8 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: 770470 (RSW-654).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2015-08-04

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138470, Methoxychlor	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

86012

Pollutant:

Methoxychlor

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 23 samples exceeded the water quality criteria/objective.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Los Angeles Region Basin Plan states "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 0.03 ug/L.

Guideline Reference:

Spatial Representation:

A total of 23 samples were collected at sampling locations, LA RIVER R-4 (9 samples), LA River R-5 (5 samples) and LA River R-7 (9 samples).

Temporal Representation:

Environmental Conditions:

There was no special environmental conditions reported.

QAPP Information:

QAPP Information Reference(s):


DECISION ID	138471	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	Mirex
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. 2 lines of evidence are available in the administrative record to assess this pollutant. 0 of 0 samples exceeded the CRITERIA. 0 of 23 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 0 and 0 of 23 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 138471, Mirex	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

86016

Pollutant:

Mirex

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 23 samples exceeded the water quality criteria/objective.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 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 Toxic Rule criteria fresh aquatic life protection maximum concentration (instantaneous) is 0.001 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 23 samples were collected at sampling locations, LA RIVER R-4 (9 samples), LA River R-5 (5 samples) and LA River R-7 (9 samples).

Temporal Representation:

Environmental Conditions:

There was no special environmental conditions reported.

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138471, Mirex	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255275

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 8 samples were collected, 8 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: 770470 (RSW-654).

Temporal Representation:

Data for this waterbody were collected over the date range 2012-02-07 to 2015-08-04

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138471, Mirex	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255293

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

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: 829991 (RSW-654(a)).

Temporal Representation:

Data for this waterbody were collected over the date range 2016-12-06 to 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138471, Mirex	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255233

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 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 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: 770468 (RSW-650).

Temporal Representation:

Data for this waterbody were collected over the date range 2012-02-07 to 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138471, Mirex	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255234

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-01 to 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138471, Mirex	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255272

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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: 833667 (RSW-LAGT650).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-01 to 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138472	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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 34 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 138472, Naphthalene	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255360

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 10 samples exceeded the water quality threshold for Naphthalene.

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:

Los Angeles River Watershed-Wide Monitoring Program

Spatial Representation:

The samples were collected at 1 monitoring site: 770468 (RSW-650).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138472, Naphthalene	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255337

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Naphthalene.

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:

Los Angeles River Watershed-Wide Monitoring Program

Spatial Representation:

The samples were collected at 1 monitoring site: 833670 (RSW-LAGT654(a)).

Temporal Representation:

The samples were collected between the dates of 2017-08-01 and 2020-08-18

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138472, Naphthalene	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255318

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Naphthalene.

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:

Los Angeles River Watershed-Wide Monitoring Program

Spatial Representation:

The samples were collected at 1 monitoring site: 829991 (RSW-654(a)).

Temporal Representation:

The samples were collected between the dates of 2016-12-06 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138472, Naphthalene	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255061

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Naphthalene.

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:

Los Angeles River Watershed-Wide Monitoring Program

Spatial Representation:

The samples were collected at 1 monitoring site: 833667 (RSW-LAGT650).

Temporal Representation:

The samples were collected between the dates of 2017-08-01 and 2020-08-18

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138472, Naphthalene	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255059

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Naphthalene.

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:

Los Angeles River Watershed-Wide Monitoring Program

Spatial Representation:

The samples were collected at 1 monitoring site: 770470 (RSW-654).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2015-08-04

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):


DECISION ID	138473	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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 66 and 0 of 46 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 138473, Nickel	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

86017

Pollutant:

Nickel

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:

None of the 46 samples exceeded the hardness adjusted criteria.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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.

Objective/Criterion 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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The River was sampled between Figueroa St. and Riverside Dr.

Temporal Representation:

One sample was collected in 2007, two samples was collected in 2008, three samples were collected in 2009, and one sample was collected in 2010.

Environmental Conditions:

There was no special environmental condition reported.

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138473, Nickel	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255346

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 14 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:

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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

The samples were collected between the dates of 2017-05-02 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138473, Nickel	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255155

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:

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: 770468 (RSW-650).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138473, Nickel	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255345

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 14 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: 833667 (RSW-LAGT650).

Temporal Representation:

The samples were collected between the dates of 2017-05-02 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138473, Nickel	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255236

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 17 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: 770470 (RSW-654).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2016-11-15

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138473, Nickel	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255222

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 2 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: 829991 (RSW-654(a)).

Temporal Representation:

The samples were collected between the dates of 2016-12-06 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138474	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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:	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. 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 16, 0n of 420 and 0 of 398 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 138474, Nitrate/Nitrite (Nitrite + Nitrate as N)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

243902

Pollutant:

Nitrate/Nitrite (Nitrite + Nitrate as N)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

126

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed data from the Los Angeles-Glendale Wastewater Reclamation Plant to determine beneficial use support. The results are as follows: 0 out of 126 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 Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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-LAGT650 (34.1377, -118.27532), located in Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.).

Temporal Representation:

The water samples were taken between 5/30/2017 -10/13/2020, per the monitoring requirements listed in the Los Angeles-Glendale Wastewater Reclamation Plant NPDES Permit monitoring and reporting program.

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the Los Angeles-Glendale Wastewater Reclamation Plant NDPES Permit quality assurance provisions for water quality monitoring.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138474, Nitrate/Nitrite (Nitrite + Nitrate as N)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

243884

Pollutant:

Nitrate/Nitrite (Nitrite + Nitrate as N)

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 data from the Los Angeles-Glendale Wastewater Reclamation Plant to determine beneficial use support. The results are as follows: 0 out of 71 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 Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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-654 (34.122833, -118.27045), located in Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.).

Temporal Representation:

The water samples were taken between 2/22/2012 - 11/8/2016, per the monitoring requirements listed in the Los Angeles-Glendale Wastewater Reclamation Plant NPDES Permit monitoring and reporting program.

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the Los Angeles-Glendale Wastewater Reclamation Plant NDPES Permit quality assurance provisions for water quality monitoring.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138474, Nitrate/Nitrite (Nitrite + Nitrate as N)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

243880

Pollutant:

Nitrate/Nitrite (Nitrite + Nitrate as N)

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 data from the Los Angeles-Glendale Wastewater Reclamation Plant to determine beneficial use support. The results are as follows: 0 out of 95 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 Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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-650 (34.134833, -118.274533), located in Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.).

Temporal Representation:

The water samples were taken between 2/15/2012 - 3/29/2017, per the monitoring requirements listed in the Los Angeles-Glendale Wastewater Reclamation Plant NPDES Permit monitoring and reporting program.

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the Los Angeles-Glendale Wastewater Reclamation Plant NDPES Permit quality assurance provisions for water quality monitoring.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138474, Nitrate/Nitrite (Nitrite + Nitrate as N)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

86018

Pollutant:

Nitrate/Nitrite (Nitrite + Nitrate as N)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

398

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

0 of the 398 samples exceeded the objective for nitrate + nitrite. Sampling data for nitrate and nitrite were summed to determine whether sampling data met the water quality objectives.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region site specific objective for Nitrogen (Nitrate + Nitrite as N) in the Los Angeles River Reach 3 is 8 mg/L. From table 3-8 titled "Water Quality Objectives for Selected Constituents in Inland Surface Waters".

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected in three locations: LAG R4, LAG R5, and LAG R7.

Temporal Representation:

Samples were collected weekly from 07/2005 through 06/2010.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138474, Nitrate/Nitrite (Nitrite + Nitrate as N)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

243951

Pollutant:

Nitrate/Nitrite (Nitrite + Nitrate as N)

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 data from the Los Angeles County MS4 Permit to determine beneficial use support. The results are as follows: 0 out of 8 samples exceed the criterion for Nitrate + Nitrite as N.

Data Reference:

WQ data from the MS4 database 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 gives a site specific objective for Nitrate + Nitrite as N in Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) of 8 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Station LAR_03_ZOO (34.155683, -118.28127), located in Los Angeles River (Zoo Dr).

Temporal Representation:

The water samples were taken between 1/20/2016 - 8/13/2019, per the monitoring requirements listed in the Los Angeles County Municipal Separate Storm Sewer Permit.

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the provisions of the Los Angeles Municipal Separate Storm Sewer System quality control and quality assurance procedures listed in coordinated integrated monitoring plan.

QAPP Information Reference(s):

WQ data from the MS4 database assembled for the 2024 Integrated Report in Region 4.

Line of Evidence (LOE) for Decision ID 138474, Nitrate/Nitrite (Nitrite + Nitrate as N)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

243950

Pollutant:

Nitrate/Nitrite (Nitrite + Nitrate as N)

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:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Los Angeles Region gives a site specific objective for Nitrate + Nitrite as N in Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) of 8 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Station LAR_03_FIG (34.081249, -118.227546), located in Los Angeles River (Figueroa St).

Temporal Representation:

The water samples were taken between 1/20/2016 - 8/13/2019, per the monitoring requirements listed in the Los Angeles County Municipal Separate Storm Sewer Permit.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 138474, Nitrate/Nitrite (Nitrite + Nitrate as N)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

243906

Pollutant:

Nitrate/Nitrite (Nitrite + Nitrate as N)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

121

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed data from the Los Angeles-Glendale Wastewater Reclamation Plant to determine beneficial use support. The results are as follows: 0 out of 121 samples exceed the criterion for Nitrate + Nitrite as N.

Data Reference:

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 Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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-LAGT654(a) (34.13, -118.27314), located in Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.).

Temporal Representation:

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the Los Angeles-Glendale Wastewater Reclamation Plant NDPES Permit quality assurance provisions for water quality monitoring.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138474, Nitrate/Nitrite (Nitrite + Nitrate as N)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

243893

Pollutant:

Nitrate/Nitrite (Nitrite + Nitrate as N)

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 data from the Los Angeles-Glendale Wastewater Reclamation Plant to determine beneficial use support. The results are as follows: 0 out of 7 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 Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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-654(a) (34.13, -118.27314), located in Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.).

Temporal Representation:

The water samples were taken between 12/20/2016 -3/29/2017, per the monitoring requirements listed in the Los Angeles-Glendale Wastewater Reclamation Plant NPDES Permit monitoring and reporting program.

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the Los Angeles-Glendale Wastewater Reclamation Plant NDPES Permit quality assurance provisions for water quality monitoring.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	149696	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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. 0 of 441 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:	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 149696, Nitrogen, Nitrate	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

302531

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 LA County MS4 data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Nitrate as N.

Data Reference:

WQ data from the MS4 database 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: LAR_03_FIG (Los Angeles River (Figueroa St)).

Temporal Representation:

The samples were collected between the dates of 2016-01-20 and 2019-08-13

Environmental Conditions:

QAPP Information:

Municipal Separate Storm Sewer System (MS4)

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 149696, Nitrogen, Nitrate	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

302585

Pollutant:

Nitrogen, Nitrate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

121

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 121 samples exceeded the water quality threshold for Nitrate as N.

Data Reference:

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: 770468 (RSW-650).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2017-04-25

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 149696, Nitrogen, Nitrate	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

302591

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 11 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: 829991 (RSW-654(a)).

Temporal Representation:

The samples were collected between the dates of 2016-12-13 and 2017-04-25

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 149696, Nitrogen, Nitrate	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

302597

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 91 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: 833667 (RSW-LAGT650).

Temporal Representation:

The samples were collected between the dates of 2017-05-09 and 2020-10-13

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 149696, Nitrogen, Nitrate	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

302522

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 MS4 database 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: LAR_03_ZOO (Los Angeles River (Zoo Dr)).

Temporal Representation:

The samples were collected between the dates of 2016-01-20 and 2019-08-13

Environmental Conditions:

QAPP Information:

Municipal Separate Storm Sewer System (MS4)

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 149696, Nitrogen, Nitrate	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

302604

Pollutant:

Nitrogen, Nitrate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

111

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 111 samples exceeded the water quality threshold for Nitrate as N.

Data Reference:

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: 770470 (RSW-654).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2016-11-30

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 149696, Nitrogen, Nitrate	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

302590

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 91 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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

The samples were collected between the dates of 2017-05-09 and 2020-10-13

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138476	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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. 1 of 61 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:	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 138476, Organophosphate Pesticides	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255656

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and the results are as follows: 0 of the 8 samples exceeded the water quality threshold for Organophosphorus Pesticides. Although a total of 16 samples were collected, 8 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 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 (833670).

Temporal Representation:

Data for this waterbody was collected over the date range 2017-05-02 to 2020-08-18

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138476, Organophosphate Pesticides	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255677

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the water quality threshold for Organophosphorus Pesticides. Although a total of 3 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 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 (829991).

Temporal Representation:

Data for this waterbody was collected over the date range 2016-12-06 to 2017-03-15

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138476, Organophosphate Pesticides	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255678

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and the results are as follows: 0 of the 21 samples exceeded the water quality threshold for Organophosphorus Pesticides. Although a total of 22 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 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 (770470).

Temporal Representation:

Data for this waterbody was collected over the date range 2012-04-17 to 2015-11-24

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138476, Organophosphate Pesticides	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255679

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and the results are as follows: 0 of the 22 samples exceeded the water quality threshold for Organophosphorus Pesticides. Although a total of 24 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

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 (770468).

Temporal Representation:

Data for this waterbody was collected over the date range 2012-04-17 to 2017-03-15

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138476, Organophosphate Pesticides	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255550

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and the results are as follows: 0 of the 8 samples exceeded the water quality threshold for Organophosphorus Pesticides. Although a total of 16 samples were collected, 8 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:

Guideline Reference:

Joint acute toxicity of Diazinon and Chlorpyrifos to Ceriodaphnia dubia.

Spatial Representation:

The samples were collected at 1 monitoring site (833667).

Temporal Representation:

Data for this waterbody was collected over the date range 2017-05-24 to 2020-05-27

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	151916	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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. Six lines of evidence are available in the administrative record to assess this pollutant. 5 of 967 samples exceeded the OBJECTIVE. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 5 of 967 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:	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 151916, Oxygen, Dissolved	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

307830

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 11 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:

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: 829991 (RSW-654(a)).

Temporal Representation:

The samples were collected between the dates of 2016-12-13 and 2017-04-25

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 151916, Oxygen, Dissolved	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

85895

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

542

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Numeric data generated from 542 averages of Dissolved Oxygen concentration had 3 exceedences.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 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 5mg/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 R-4, R-5, and R-7 monitoring locations.

Temporal Representation:

Samples were collected approximately once a week from July 2005 to June 2010.

Environmental Conditions:

QAPP Information:

The quality assurance manual for the Environmental Monitoring Division Bureau of Sanitation, Department of Public Works, City of Los Angeles was provided. Toxicity testing methods and requirements are in the NPDES permit CA0056227.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 151916, Oxygen, Dissolved	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

307802

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

111

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 1 of 111 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: 770470 (RSW-654).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2016-11-30

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 151916, Oxygen, Dissolved	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

308179

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 91 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: 833667 (RSW-LAGT650).

Temporal Representation:

The samples were collected between the dates of 2017-05-09 and 2020-10-13

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 151916, Oxygen, Dissolved	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

308006

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

121

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 121 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: 770468 (RSW-650).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2017-04-25

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 151916, Oxygen, Dissolved	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

307856

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 1 of 91 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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

The samples were collected between the dates of 2017-05-09 and 2020-10-13

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138481	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	PCBs (Polychlorinated biphenyls)
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. 6 lines of evidence are available in the administrative record to assess this pollutant. 0 of 23 samples exceeded the CRITERIA. 0 of 23 samples exceeded the CRITERIA. 0 of 0 samples exceeded the CRITERIA. 0 of 0 samples exceeded the CRITERIA. 0 of 23 samples exceeded the CRITERIA. 0 of 0 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. 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 23, 0 of 23, 0 of 0, 0 of 0, 0 of 23 and 0 of 0 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 138481, PCBs (Polychlorinated biphenyls)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255448

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 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 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: 833667 (RSW-LAGT650).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-01 to 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138481, PCBs (Polychlorinated biphenyls)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255723

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 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:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 833670 (RSW-LAGT654(a)).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-01 to 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138481, PCBs (Polychlorinated biphenyls)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

85896

Pollutant:

PCB (Polychlorinated biphenyl)-1242

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:

The reporting limits for all 23 of the non-detect samples were greater than the criteria, therefore were not used in this assessment.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 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:

The CTR for freshwater habitat, continuous concentration, is 0.014 ug/L for total PCBs.

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:

The River was sampled between Figueroa St. and Riverside Dr.

Temporal Representation:

One sample was collected in 2007, two samples was collected in 2008, three samples were collected in 2009, and one sample was collected in 2010.

Environmental Conditions:

There was no special environmental condition reported.

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138481, PCBs (Polychlorinated biphenyls)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

85897

Pollutant:

PCB (Polychlorinated biphenyl)-1248

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:

The reporting limits for all 23 of the non-detect samples were greater than the criteria, therefore were not used in this assessment.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 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:

The CTR for freshwater habitat, continuous concentration, is 0.014 ug/L for total PCBs.

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:

The River was sampled between Figueroa St. and Riverside Dr.

Temporal Representation:

One sample was collected in 2007, two samples was collected in 2008, three samples were collected in 2009, and one sample was collected in 2010.

Environmental Conditions:

There was no special environmental condition reported.

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138481, PCBs (Polychlorinated biphenyls)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

85898

Pollutant:

PCB (Polychlorinated biphenyl)-1254

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:

The reporting limits for all 23 of the non-detect samples were greater than the criteria, therefore were not used in this assessment.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 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:

The CTR for freshwater habitat, continuous concentration, is 0.014 ug/L for total PCBs.

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:

The River was sampled between Figueroa St. and Riverside Dr.

Temporal Representation:

One sample was collected in 2007, two samples was collected in 2008, three samples were collected in 2009, and one sample was collected in 2010.

Environmental Conditions:

There was no special environmental condition reported.

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138481, PCBs (Polychlorinated biphenyls)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

85911

Pollutant:

PCB (Polychlorinated biphenyl)-1260

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:

The reporting limits for all 23 of the non-detect samples were greater than the criteria, therefore were not used in this assessment.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 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:

The CTR for freshwater habitat, continuous concentration, is 0.014 ug/L for total PCBs.

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:

The River was sampled between Figueroa St. and Riverside Dr.

Temporal Representation:

One sample was collected in 2007, two samples was collected in 2008, three samples were collected in 2009, and one sample was collected in 2010.

Environmental Conditions:

There was no special environmental condition reported.

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138481, PCBs (Polychlorinated biphenyls)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

85912

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

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 twenty three samples exceeded the evaluation guideline.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for total PCBs is 676 ug/Kg dry weight.

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Sediment samples were collected at station LA River R4, LA River R5 and LA River R7.

Temporal Representation:

Samples were collected in 2006 on February 7 and August 2, and in 2007 on February 7.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138481, PCBs (Polychlorinated biphenyls)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255425

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 8 samples were collected, 8 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: 770470 (RSW-654).

Temporal Representation:

Data for this waterbody were collected over the date range 2012-02-07 to 2015-08-04

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138481, PCBs (Polychlorinated biphenyls)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255447

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

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: 829991 (RSW-654(a)).

Temporal Representation:

Data for this waterbody were collected over the date range 2016-12-06 to 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138481, PCBs (Polychlorinated biphenyls)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255683

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 770468 (RSW-650).

Temporal Representation:

Data for this waterbody were collected over the date range 2012-02-07 to 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138478	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	Parathion
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 138478, Parathion	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255531

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

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: 829991 (RSW-654(a)).

Temporal Representation:

Data for this waterbody were collected over the date range 2016-12-06 to 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138478, Parathion	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255467

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 8 samples were collected, 8 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: 833667 (RSW-LAGT650).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-01 to 2020-08-18

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138478, Parathion	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255444

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 9 samples were collected, 9 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: 770470 (RSW-654).

Temporal Representation:

Data for this waterbody were collected over the date range 2012-02-07 to 2015-11-03

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138478, Parathion	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255532

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 8 samples were collected, 8 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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-01 to 2020-08-18

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138478, Parathion	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255510

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 11 samples were collected, 11 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: 770468 (RSW-650).

Temporal Representation:

Data for this waterbody were collected over the date range 2012-02-07 to 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138479	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	Pentachlorophenol (PCP)
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 138479, Pentachlorophenol (PCP)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

85913

Pollutant:

Pentachlorophenol (PCP)

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:

The reporting limits for all 23 of the non-detect samples were greater than the criteria, therefore were not used in this assessment.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 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:

The California Toxic Rule, 4-day avg. at pH 6.5 is 4 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:

The River was sampled between Figueroa St. and Riverside Dr.

Temporal Representation:

One sample was collected in 2007, two samples was collected in 2008, three samples were collected in 2009, and one sample was collected in 2010.

Environmental Conditions:

There was no special environmental condition reported.

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138479, Pentachlorophenol (PCP)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255623

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the water quality threshold for Pentachlorophenol. Although a total of 9 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

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 (770470).

Temporal Representation:

Data for this waterbody was collected over the date range 2012-02-07 to 2016-11-15

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138509	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	Permethrin
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 138509, Permethrin	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

265002

Pollutant:

Permethrin

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 Surface Water Monitoring Project data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Permethrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

WQ data from the California Environmental Data Exchange Network 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 chronic criterion for permethrin is 1 ng/L (expressed as a 4-day average). If the freely dissolved concentrations of permethrin were reported or could be calculated then these values were used for this assessment. In the absence of freely dissolved concentrations, total concentrations were used.

Guideline Reference:

Water Quality Criteria Report for Permethrin

Spatial Representation:

The samples were collected at 1 monitoring site: Los Angeles 247 (Los Angeles River upper watershed).

Temporal Representation:

Data for this waterbody were collected over the date range 2015-06-03 to 2015-06-03

Environmental Conditions:

QAPP Information:

Department of Pesticide Regulation Environmental Monitoring Branch Surface Water Protection Program. 2018. STUDY 270: Ambient Surface Water and Mitigation Monitoring in Urban Areas in Southern.

QAPP Information Reference(s):

STUDY 270: Ambient Surface Water and Mitigation Monitoring in Urban Areas in Southern


DECISION ID	138491	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	Pyrethroids
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 138491, Pyrethroids	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

265418

Pollutant:

Pyrethroids

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 Surface Water Monitoring Project data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Pyrethroids. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

WQ data from the California Environmental Data Exchange Network 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 summed ratios of the pyrethroid pesticides bifenthrin, cyfluthrin, cypermethrin, esfenvalerate, lambda-cyhalothrin, permethrin and their respective chronic concentration goals are not to exceed 1. If the freely dissolved concentrations of these pesticides were reported or could be calculated then these values were used for this assessment. In the absence of freely dissolved concentrations, total concentrations were used.

Guideline Reference:

Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges

Spatial Representation:

The samples were collected at 1 monitoring site: Los Angeles 247 (Los Angeles River upper watershed).

Temporal Representation:

Data for this waterbody were collected over the date range 2015-06-03 to 2015-06-03

Environmental Conditions:

QAPP Information:

Department of Pesticide Regulation Environmental Monitoring Branch Surface Water Protection Program. 2018. STUDY 270: Ambient Surface Water and Mitigation Monitoring in Urban Areas in Southern.

QAPP Information Reference(s):

STUDY 270: Ambient Surface Water and Mitigation Monitoring in Urban Areas in Southern


DECISION ID	138482	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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. 2 lines of evidence are available in the administrative record to assess this pollutant. 0 of 31 samples exceeded the CRITERIA. 0 of 66 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 66 and 0 of 31 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 138482, Selenium	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255384

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 14 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: 833667 (RSW-LAGT650).

Temporal Representation:

The samples were collected between the dates of 2017-05-02 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138482, Selenium	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255803

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 2 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: 829991 (RSW-654(a)).

Temporal Representation:

The samples were collected between the dates of 2016-12-06 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138482, Selenium	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255873

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 17 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: 770470 (RSW-654).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2016-11-15

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138482, Selenium	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255411

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: 770468 (RSW-650).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138482, Selenium	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255846

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 14 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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

The samples were collected between the dates of 2017-05-02 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138482, Selenium	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

85915

Pollutant:

Selenium

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:

None of the 31 samples exceeded the criteria.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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.

Objective/Criterion 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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The River was sampled between Figueroa St. and Riverside Dr.

Temporal Representation:

One sample was collected in 2007, two samples was collected in 2008, three samples were collected in 2009, and one sample was collected in 2010.

Environmental Conditions:

There was no special environmental condition reported.

QAPP Information:

QAPP Information Reference(s):


DECISION ID	138483	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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. 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 66 and 0 of 31 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 138483, Silver	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255982

Pollutant:

Silver

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 14 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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

The samples were collected between the dates of 2017-05-02 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138483, Silver	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255983

Pollutant:

Silver

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 17 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:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 770470 (RSW-654).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2016-11-15

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138483, Silver	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

256001

Pollutant:

Silver

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: 770468 (RSW-650).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138483, Silver	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255812

Pollutant:

Silver

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 2 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:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 829991 (RSW-654(a)).

Temporal Representation:

The samples were collected between the dates of 2016-12-06 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138483, Silver	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255829

Pollutant:

Silver

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 14 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:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 833667 (RSW-LAGT650).

Temporal Representation:

The samples were collected between the dates of 2017-05-02 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138483, Silver	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

85932

Pollutant:

Silver

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:

None of the 31 samples exceeded the hardness adjusted criteria.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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.

Objective/Criterion 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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The River was sampled between Figueroa St. and Riverside Dr.

Temporal Representation:

One sample was collected in 2007, two samples was collected in 2008, three samples were collected in 2009, and one sample was collected in 2010.

Environmental Conditions:

There was no special environmental condition reported.

QAPP Information:

QAPP Information Reference(s):


DECISION ID	138484	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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 65 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:	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 138484, Sulfates	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

243907

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:

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 Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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-LAGT654(a) (34.13, -118.27314), located in Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.).

Temporal Representation:

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the Los Angeles-Glendale Wastewater Reclamation Plant NDPES Permit quality assurance provisions for water quality monitoring.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138484, Sulfates	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

243881

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 Los Angeles-Glendale Wastewater Reclamation Plant to determine beneficial use support. The results are as follows: 0 out of 18 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 Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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-650 (34.134833, -118.274533), located in Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.).

Temporal Representation:

The water samples were taken between 5/1/2012 - 2/16/2017, per the monitoring requirements listed in the Los Angeles-Glendale Wastewater Reclamation Plant NPDES Permit monitoring and reporting program.

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the Los Angeles-Glendale Wastewater Reclamation Plant NDPES Permit quality assurance provisions for water quality monitoring.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138484, Sulfates	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

243885

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:

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 Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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-654 (34.122833, -118.27045), located in Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.).

Temporal Representation:

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the Los Angeles-Glendale Wastewater Reclamation Plant NDPES Permit quality assurance provisions for water quality monitoring.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138484, Sulfates	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

243894

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:

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 Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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-654(a) (34.13, -118.27314), located in Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.).

Temporal Representation:

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the Los Angeles-Glendale Wastewater Reclamation Plant NDPES Permit quality assurance provisions for water quality monitoring.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138484, Sulfates	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

243903

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:

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 Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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-LAGT650 (34.1377, -118.27532), located in Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.).

Temporal Representation:

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the Los Angeles-Glendale Wastewater Reclamation Plant NDPES Permit quality assurance provisions for water quality monitoring.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138485	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	Temperature, water
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(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. 2 lines of evidence are available in the administrative record to assess this pollutant. 0 of 235 samples exceeded the objective. 0 of 766 samples exceeded the objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 0 of 235 and 0 of 766 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:	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 138485, Temperature, water	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255922

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

214

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 214 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:

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: 770468 (RSW-650).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2017-04-25

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138485, Temperature, water	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

85933

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

235

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

0 of the 235 samples exceeded the evaluation guideline for water temperature.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

For waters designated as WARM, water temperature shall not be altered more than 5 degrees F above the natural temperature. At no time shall these WARM designated waters be raised above 80 degrees F as a result of waste discharges.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

At no time shall these WARM designated waters be raised above 80 degrees F

Guideline Reference:

Fish introductions in CA: History and impact on native fishes. Davis, CA: University of CA, Davis

Spatial Representation:

Samples were collected at three locations in Reach 3 of the Los Angeles River: Site 1: Lat. 34.1377167 Lon. -118.2753667, Site 2: Lat. 34.1348333 Lon. -118.2745333, Site 3: Lat. 34.1228333 Lon. -118.2704500

Temporal Representation:

Samples collected between July 2005 and June 2010.

Environmental Conditions:

QAPP Information:

QUALITY ASSURANCE MANUAL Prepared for The Analysts, Supervisors, and Managers of the Environmental Monitoring Division ENVIRONMENTAL MONITORING DIVISION BUREAU OF SANITATION DEPARTMENT OF PUBLIC WORKS CITY OF LOS ANGELES, December 2009

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138485, Temperature, water	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255858

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

197

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 197 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: 770470 (RSW-654).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2016-11-30

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138485, Temperature, water	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255941

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 17 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: 829991 (RSW-654(a)).

Temporal Representation:

The samples were collected between the dates of 2016-12-06 and 2017-04-25

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138485, Temperature, water	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255966

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

169

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 169 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: 833667 (RSW-LAGT650).

Temporal Representation:

The samples were collected between the dates of 2017-05-02 and 2020-10-13

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138485, Temperature, water	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255989

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

169

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 169 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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

The samples were collected between the dates of 2017-05-02 and 2020-10-13

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138486	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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 66 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 138486, Thallium	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255906

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 2 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: 829991 (RSW-654(a)).

Temporal Representation:

The samples were collected between the dates of 2016-12-06 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138486, Thallium	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255773

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: 770468 (RSW-650).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138486, Thallium	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255770

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 17 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: 770470 (RSW-654).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2016-11-15

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138486, Thallium	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255757

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 14 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: 833667 (RSW-LAGT650).

Temporal Representation:

The samples were collected between the dates of 2017-05-02 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138486, Thallium	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

256036

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 14 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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

The samples were collected between the dates of 2017-05-02 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138487	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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. 0 of 66 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:	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 138487, Total Dissolved Solids	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

243904

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:

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 Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) of 950 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Station RSW-LAGT650 (34.1377, -118.27532), located in Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.).

Temporal Representation:

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the Los Angeles-Glendale Wastewater Reclamation Plant NDPES Permit quality assurance provisions for water quality monitoring.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138487, Total Dissolved Solids	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

243891

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:

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 Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) of 950 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Station RSW-654 (34.122833, -118.27045), located in Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.).

Temporal Representation:

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the Los Angeles-Glendale Wastewater Reclamation Plant NDPES Permit quality assurance provisions for water quality monitoring.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138487, Total Dissolved Solids	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

243882

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:

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 Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) of 950 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Station RSW-650 (34.134833, -118.274533), located in Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.).

Temporal Representation:

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the Los Angeles-Glendale Wastewater Reclamation Plant NDPES Permit quality assurance provisions for water quality monitoring.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138487, Total Dissolved Solids	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

243914

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:

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 Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) of 950 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Station RSW-LAGT654(a) (34.13, -118.27314), located in Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.).

Temporal Representation:

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the Los Angeles-Glendale Wastewater Reclamation Plant NDPES Permit quality assurance provisions for water quality monitoring.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138487, Total Dissolved Solids	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

243895

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:

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 Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) of 950 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Station RSW-654(a) (34.13, -118.27314), located in Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.).

Temporal Representation:

Environmental Conditions:

QAPP Information:

The work was performed in accordance with the Los Angeles-Glendale Wastewater Reclamation Plant NDPES Permit quality assurance provisions for water quality monitoring.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138488	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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 138488, Toxaphene	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

256178

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 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 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: 833667 (RSW-LAGT650).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-01 to 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138488, Toxaphene	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

85935

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 from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 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 23 samples were collected at sampling locations, LA RIVER R-4 (9 samples), LA River R-5 (5 samples) and LA River R-7 (9 samples).

Temporal Representation:

Environmental Conditions:

There was no special environmental conditions reported.

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138488, Toxaphene	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

256261

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 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 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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-01 to 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138488, Toxaphene	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

256246

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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: 770468 (RSW-650).

Temporal Representation:

Data for this waterbody were collected over the date range 2012-02-07 to 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138488, Toxaphene	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

256213

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

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: 829991 (RSW-654(a)).

Temporal Representation:

Data for this waterbody were collected over the date range 2016-12-06 to 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138488, Toxaphene	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

256110

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) 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 8 samples were collected, 8 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: 770470 (RSW-654).

Temporal Representation:

Data for this waterbody were collected over the date range 2012-02-07 to 2015-08-04

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138498	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	Triclopyr
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 138498, Triclopyr	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

267774

Pollutant:

Triclopyr

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 Environmental Data Exchange Network 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 triclopyr is the USEPA Aquatic Life Benchmark of 26 ug/L for a fish (chronic) for Triclopyr Butoxyethyl Ester (BEE).

Guideline Reference:

STUDY 270: Ambient Surface Water and Mitigation Monitoring in Urban Areas in Southern

Spatial Representation:

The samples were collected at 1 monitoring site: Los Angeles 247 (Los Angeles River upper watershed).

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

Department of Pesticide Regulation Environmental Monitoring Branch Surface Water Protection Program. 2018. STUDY 270: Ambient Surface Water and Mitigation Monitoring in Urban Areas in Southern.

QAPP Information Reference(s):


DECISION ID	138489	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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. 0 of 66 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:	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 138489, Turbidity	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

256216

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 17 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: 770470 (RSW-654).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2016-11-15

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138489, Turbidity	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

256285

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 14 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:

Guideline Reference:

The Effects of Turbidity on Prey Selection by Piscivorous Largemouth Bass

Spatial Representation:

The samples were collected at 1 monitoring site: 833670 (RSW-LAGT654(a)).

Temporal Representation:

The samples were collected between the dates of 2017-05-02 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138489, Turbidity	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

256295

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: 770468 (RSW-650).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138489, Turbidity	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

256217

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 14 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:

Guideline Reference:

The Effects of Turbidity on Prey Selection by Piscivorous Largemouth Bass

Spatial Representation:

The samples were collected at 1 monitoring site: 833667 (RSW-LAGT650).

Temporal Representation:

The samples were collected between the dates of 2017-05-02 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138489, Turbidity	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

256186

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 2 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:

Guideline Reference:

The Effects of Turbidity on Prey Selection by Piscivorous Largemouth Bass

Spatial Representation:

The samples were collected at 1 monitoring site: 829991 (RSW-654(a)).

Temporal Representation:

The samples were collected between the dates of 2016-12-06 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138490	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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. 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 18, 4 of 75 and 0 of 93 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 138490, Zinc	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

252896

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 MS4 database 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: LAR_03_ZOO (Los Angeles River (Zoo Dr)).

Temporal Representation:

The samples were collected between the dates of 2016-01-20 and 2019-08-13

Environmental Conditions:

QAPP Information:

Municipal Separate Storm Sewer System (MS4)

QAPP Information Reference(s):

WQ data from the MS4 database assembled for the 2024 Integrated Report in Region 4.

Line of Evidence (LOE) for Decision ID 138490, Zinc	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

252899

Pollutant:

Zinc

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 LA County MS4 data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Zinc.

Data Reference:

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: LAR_03_ZOO (Los Angeles River (Zoo Dr)).

Temporal Representation:

The samples were collected between the dates of 2016-08-20 and 2018-05-15

Environmental Conditions:

QAPP Information:

Municipal Separate Storm Sewer System (MS4)

QAPP Information Reference(s):

WQ data from the MS4 database assembled for the 2024 Integrated Report in Region 4.

Line of Evidence (LOE) for Decision ID 138490, Zinc	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

253039

Pollutant:

Zinc

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 LA County MS4 data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 4 of 7 samples exceeded the water quality threshold for Zinc.

Data Reference:

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: LAR_03_FIG (Los Angeles River (Figueroa St)).

Temporal Representation:

The samples were collected between the dates of 2016-08-20 and 2019-11-27

Environmental Conditions:

QAPP Information:

Municipal Separate Storm Sewer System (MS4)

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 138490, Zinc	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

256104

Pollutant:

Zinc

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Zinc.

Data Reference:

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: 829991 (RSW-654(a)).

Temporal Representation:

The samples were collected between the dates of 2016-12-06 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138490, Zinc	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

256158

Pollutant:

Zinc

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 17 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:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 770470 (RSW-654).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2016-11-15

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138490, Zinc	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

256221

Pollutant:

Zinc

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: 770468 (RSW-650).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138490, Zinc	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

256223

Pollutant:

Zinc

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 14 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:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 833670 (RSW-LAGT654(a)).

Temporal Representation:

The samples were collected between the dates of 2017-05-02 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138490, Zinc	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

85953

Pollutant:

Zinc

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:

None of the 93 samples exceeded the hardness adjusted criteria.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion 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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The River was sampled between Figueroa St. and Riverside Dr.

Temporal Representation:

One sample was collected in 2007, two samples was collected in 2008, three samples were collected in 2009, and one sample was collected in 2010.

Environmental Conditions:

There was no special environmental condition reported.

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138490, Zinc	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

252991

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 LA County MS4 data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 10 samples exceeded the water quality threshold for Zinc.

Data Reference:

WQ data from the MS4 database 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: LAR_03_FIG (Los Angeles River (Figueroa St)).

Temporal Representation:

The samples were collected between the dates of 2016-01-20 and 2019-08-13

Environmental Conditions:

QAPP Information:

Municipal Separate Storm Sewer System (MS4)

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 138490, Zinc	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

256107

Pollutant:

Zinc

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 14 samples exceeded the water quality threshold for Zinc.

Data Reference:

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: 833667 (RSW-LAGT650).

Temporal Representation:

The samples were collected between the dates of 2017-05-02 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138460	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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 34 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 138460, alpha-Endosulfan (Endosulfan 1)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254623

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Endosulfan I.

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: 770470 (RSW-654).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2015-08-04

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138460, alpha-Endosulfan (Endosulfan 1)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254652

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Endosulfan I.

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: 833667 (RSW-LAGT650).

Temporal Representation:

The samples were collected between the dates of 2017-08-01 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138460, alpha-Endosulfan (Endosulfan 1)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254603

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 10 samples exceeded the water quality threshold for Endosulfan I.

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: 770468 (RSW-650).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138460, alpha-Endosulfan (Endosulfan 1)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254671

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Endosulfan I.

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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

The samples were collected between the dates of 2017-08-01 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138460, alpha-Endosulfan (Endosulfan 1)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254555

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Endosulfan I.

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: 829991 (RSW-654(a)).

Temporal Representation:

The samples were collected between the dates of 2016-12-06 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138477	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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 34 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 138477, beta-Endosulfan (Endosulfan 2)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254345

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Endosulfan II.

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: 770470 (RSW-654).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2015-08-04

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138477, beta-Endosulfan (Endosulfan 2)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254380

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Endosulfan II.

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: 829991 (RSW-654(a)).

Temporal Representation:

The samples were collected between the dates of 2016-12-06 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138477, beta-Endosulfan (Endosulfan 2)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254373

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Endosulfan II.

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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

The samples were collected between the dates of 2017-08-01 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138477, beta-Endosulfan (Endosulfan 2)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254355

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 10 samples exceeded the water quality threshold for Endosulfan II.

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: 770468 (RSW-650).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2017-02-16

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138477, beta-Endosulfan (Endosulfan 2)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

254354

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:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Endosulfan II.

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: 833667 (RSW-LAGT650).

Temporal Representation:

The samples were collected between the dates of 2017-08-01 and 2020-08-11

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	138480	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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. 1 line of evidence is available in the administrative record to assess this pollutant. 23 of 967 samples exceeded the OBJECTIVE. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. 23 of 967 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:	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 138480, pH	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

85914

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

542

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Seven of the 542 samples exceeded the objective.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 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 R-4, R-5, and R-7 monitoring locations.

Temporal Representation:

Samples were collected approximately once a week from July 2005 to June 2010.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 138480, pH	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255504

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 91 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: 833670 (RSW-LAGT654(a)).

Temporal Representation:

The samples were collected between the dates of 2017-05-09 and 2020-10-13

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138480, pH	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255403

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

121

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 10 of 121 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: 770468 (RSW-650).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2017-04-25

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138480, pH	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255479

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 6 of 91 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: 833667 (RSW-LAGT650).

Temporal Representation:

The samples were collected between the dates of 2017-05-09 and 2020-10-13

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138480, pH	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255404

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_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 11 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: 829991 (RSW-654(a)).

Temporal Representation:

The samples were collected between the dates of 2016-12-13 and 2017-04-25

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program

Line of Evidence (LOE) for Decision ID 138480, pH	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

255689

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

111

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed eSMR_Los Angeles-Glendale WWRP data for Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.) to determine beneficial use support and results are as follows: 0 of 111 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: 770470 (RSW-654).

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2016-11-30

Environmental Conditions:

QAPP Information:

Los Angeles & San Gabriel Rivers Watershed Council. 2010. Los Angeles River Watershed-Wide Monitoring Program.

QAPP Information Reference(s):

Los Angeles River Watershed-Wide Monitoring Program


DECISION ID	72373	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	Scum/Foam-unnatural
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:	Pollution

Regional Board Conclusion:	This pollutant is being considered for removal from the section 303(d) list under section 4 of the Listing Policy. Under this section of the Policy, a minimum of one line of evidence is needed to assess listing status. One line of evidence is available in the administrative record to assess this water body condition. A nitrogen TMDL has been developed and approved by USEPA and an approved implementation plan is expected to result in attainment of the nitrogen standard. Qualitative information on scum/foam-unnatural alone is not sufficient to support placement on the section 303(d) list (Listing Policy section 3.7). It is expected that this TMDL will address the pollutant(s) contributing to or causing these conditions. The Los Angeles River Nitrogen TMDL was approved by RWQCB on August 19, 2003 and subsequently approved by USEPA on March 18, 2004. This TMDL will address this water body condition. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of removing this water segment-pollutant combination from the section 303(d) list.

Regional Board Decision Recommendation:	This is a decision previously approved by the State Water Resources Control Board and the USEPA. No new data were assessed by the Regional Board for the current cycle. The decision has not changed.

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 72373, Scum/Foam-unnatural	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

2506

Pollutant:

Scum/Foam-unnatural

LOE Subgroup:

Narrative Description Data

Matrix:

Not Specified

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

A TMDL and implementation plan has been approved for this water segment-pollutant combination. The Los Angeles River Nitrogen TMDL was approved by RWQCB on August 19, 2003 and subsequently approved by USEPA on March 18, 2004. This TMDL will address this water body condition.

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

QA Info Missing

QAPP Information Reference(s):


DECISION ID	69968	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	Taste and odor
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:	Flaws in original listing
Impairment from Pollutant or Pollution:	Pollution

Regional Board Conclusion:	This pollutant is being considered for removal from the section 303(d) list under section 4 of the Listing Policy. Under this section of the Policy, a minimum of one line of evidence is needed to assess listing status. One line of evidence is available in the administrative record to assess this water body condition. A nitrogen TMDL has been developed and approved by USEPA and an approved implementation plan is expected to result in attainment of the nitrogen standard. Qualitative information on taste and odor alone is not sufficient to support placement on the section 303(d) list (Listing Policy section 3.7). It is expected that this TMDL will address the pollutant(s) contributing to or causing this condition. The Los Angeles River Nitrogen TMDL was approved by RWQCB on August 19, 2003 and subsequently approved by USEPA on March 18, 2004.

Regional Board Decision Recommendation:	This is a decision previously approved by the State Water Resources Control Board and the USEPA. No new data were assessed by the Regional Board for the current cycle. The decision has not changed.

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 69968, Taste and odor	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

2505

Pollutant:

Taste and odor

LOE Subgroup:

Pollutant-Water

Matrix:

Not Specified

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

QA Info Missing

QAPP Information Reference(s):


DECISION ID	70709	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	Lead
Final Listing Decision:	Delist from 303(d) list (being addressed by USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision:	Delist from 303(d) list (being addressed by USEPA approved TMDL)(2016)
Revision Status	Original
Reason for Delisting:	Applicable WQS attained; due to restoration activities
TMDL Name:	Los Angeles River Metals (13)
TMDL Project Code:	237
Date TMDL Approved by USEPA:	12/22/2005
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 4.1 of the Listing Policy. Under this section 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. 1 of the 93 samples exceeded the CRITERIA. 0 of the 0 samples exceeded the CRITERIA. 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. 1 of 93 and 0 of 0 samples exceeded the CRITERIA and this does not exceed the allowable frequency listed in Table 4.1 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 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 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 70709, Lead	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

86010

Pollutant:

Lead

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:

One of the 93 samples exceeded the hardness adjusted criteria.

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion 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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The River was sampled between Figueroa St. and Riverside Dr.

Temporal Representation:

One sample was collected in 2007, two samples was collected in 2008, three samples were collected in 2009, and one sample was collected in 2010.

Environmental Conditions:

There was no special environmental condition reported.

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 70709, Lead	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

2511

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Not Specified

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Unspecified--This LOE is a placeholder to support a listing decision made by USEPA for 2006.

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

QA Info Missing

QAPP Information Reference(s):


DECISION ID	69733	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	Copper
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:	Los Angeles River Metals (13)
TMDL Project Code:	237
Date TMDL Approved by USEPA:	10/29/2008
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for removal on the CWA section 303(d) List under sections 2.2 and 3.1 of the Listing Policy. Under SECTION 3.1 of the Policy, a minimum of one line of evidence is needed to assess listing status. 2 lines of evidence are 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 removing this water segment-pollutant combination from the CWA section 303(d) List. There is sufficient justification to place it in the Being Addressed portion of the CWA 303(d) List because a TMDL has been completed and approved by RWQCB and USEPA, and is expected to result in attainment of the standard. 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 93 samples exceeded the CRITERIA and these exceed the allowable frequency listed in Table 3.1of the Listing Policy. 4. The Los Angeles Metals TMDL was approved by USEPA on 12/22/2005 5. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not 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 Los Angeles River Metals TMDL was approved by USEPA on 10/29/2008.

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 69733, Copper	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

2510

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Not Specified

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Unspecified--This LOE is a placeholder to support a listing decision made by USEPA for 2006.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

QA Info Missing

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 69733, Copper	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

85997

Pollutant:

Copper

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:

Eight of the 93 samples exceeded the hardness adjusted criteria.

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion 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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The River was sampled between Figueroa St. and Riverside Dr.

Temporal Representation:

One sample was collected in 2007, two samples was collected in 2008, three samples were collected in 2009, and one sample was collected in 2010.

Environmental Conditions:

There was no special environmental condition reported.

QAPP Information:

QAPP Information Reference(s):


DECISION ID	99749	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	Benthic Community Effects
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:	Benthic Community Effects is being considered for placement on the CWA section 303(d) List under sections 3.9 of the Listing Policy. Under section 3.9, additional lines of evidence associating the Benthic Community Effects with a water or sediment concentration of pollutants and there are multiple lines of evidence for other impairments. Three samples were collected from the Los Angeles River Reach 3 over three years. Four of the four samples collected had an IBI score below 40. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing Benthic Community Effects in this water segment on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Three samples were collected from Los Angeles River Reach 3over two years. Four of the four samples collected had an IBI score below 40. However, the Los Angeles Water Board has identified this waterbody as needing further monitoring and data collection. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. The CSCI is applicable statewide, accounts for a much wider range of natural variability, and provides equivalent scoring thresholds in all regions of the state. The CSCI will be used in the future for water quality assessment purposes statewide over the regional indices of biologic integrity (IBIs).

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:	The CSCI is applicable statewide, accounts for a much wider range of natural variability, and provides equivalent scoring thresholds in all regions of the state. The CSCI will be used in the future for water quality assessment purposes statewide over the regional indices of biologic integrity (IBIs).

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 99749, Benthic Community Effects	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

85994

Pollutant:

Benthic-Macroinvertebrate Bioassessments

LOE Subgroup:

Population/Community Degradation

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Benthic macroinvertebrate surveys

Data Used to Assess Water Quality:

Four samples were collected from two sites on the Los Angeles River over two years. Four of the four samples collected had IBI scores below 40. The scores were 7 and 0 (2006) and 17 and 0 (2007).

Data Reference:

Bioassessment Monitoring Report in Los Angeles County, 2006-2008.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration or other appropriate methods as specified by the State or Regional Board.

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

The IBI is a multi-metric assessment that employs biological metrics that respond to a habitat or water quality impairment. Each of the biological metrics measured at a site are converted to an IBI score then summed. These cumulative scores are then ranked. For the Southern California IBI, sites with scores below 40 are considered to have impaired conditions.

Guideline Reference:

Development of a Benthic Index of Biotic Integrity (B-IBI) for Wadeable Streams in Northern Coastal California and its Application to Regional 305(b) Assessment

Spatial Representation:

The samples were collected from Los Angeles River near confluence with Arroyo Seco Channel, station 12 and Los Angeles River at Victory Blvd, station 11.

Temporal Representation:

The samples were collected in 2006 and 2007.

Environmental Conditions:

QAPP Information:

Qaulity assurance is good. Los Angeles County Department of Public Works (LACDPW) contracted Weston Solutions, Inc. to perform biological assessments. Sampling and analysis followed the protocols described in the California Stream Bioassessment Procedure (CSBP) (Harrington, 2003), and also incorporated the Southern California Index of Biotic Integrity (IBI) (Ode et al., 2005).

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 99749, Benthic Community Effects	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

28079

Pollutant:

Trash

LOE Subgroup:

Narrative Description Data

Matrix:

Not Specified

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

A TMDL has been approved for this water segment-pollutant combination. The Trash TMDL for the Los Angeles River Watershed was adopted by the Los Angeles RWQCB on August 09, 2007 and subsequently approved by USEPA. The TMDL was been integrated into the Basin Plan as Attachment A of Regional Board Resolution No. 2007-012.

Data Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

QA information unavailable.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 99749, Benthic Community Effects	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

85894

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

20 out of 60 monthly averages exceeded the site specific basin plan objective for total ammonia as nitrogen. All the exceedences were 2007 and prior.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 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 in three locations: LAG R4, LAG R5, and LAG R7.

Temporal Representation:

Samples were collected weekly from 07/2005 through 06/2010. Only samples collected from the months of April 1 to September 30 have been included.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 99749, Benthic Community Effects	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

86019

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

13 out of 51 monthly averages exceeded the site specific basin plan objective for total ammonia as nitrogen. All exceedences occurred 2007 and prior.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 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 in three locations: LAG R4, LAG R5, and LAG R7.

Temporal Representation:

Samples were collected weekly from 07/2005 through 06/2010. Only samples collected from the months of October 1 to March 31 have been included.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 99749, Benthic Community Effects	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

86010

Pollutant:

Lead

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:

One of the 93 samples exceeded the hardness adjusted criteria.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion 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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The River was sampled between Figueroa St. and Riverside Dr.

Temporal Representation:

One sample was collected in 2007, two samples was collected in 2008, three samples were collected in 2009, and one sample was collected in 2010.

Environmental Conditions:

There was no special environmental condition reported.

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 99749, Benthic Community Effects	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

2511

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Not Specified

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Unspecified--This LOE is a placeholder to support a listing decision made by USEPA for 2006.

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

QA Info Missing

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 99749, Benthic Community Effects	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

2504

Pollutant:

Nutrients (Algae)

LOE Subgroup:

Pollutant-Water

Matrix:

Not Specified

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

QA Info Missing

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 99749, Benthic Community Effects	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

85936

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:

Seventy-five samples were collected to evaluate water toxicity. Twenty-nine of the 75 samples exhibited significant toxicity. The toxicity tests included acute toxicity using Atherinops affinis and chronic toxicity using Ceriodaphnia dubia, Selenastrum capricornutum and Pimephales promelas.

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. The t-test is used to determine if there is a statistically significant decrease in organism response in the sample as compared to the control.

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:

The samples were collected at Los Angeles River R4, R5 and R7.

Temporal Representation:

The samples were collected every three months from November 2005 to May 2010.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 99749, Benthic Community Effects	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

2507

Pollutant:

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:

Not Specified

Data Used to Assess Water Quality:

Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

QA Info Missing

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 99749, Benthic Community Effects	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

2508

Pollutant:

Trash

LOE Subgroup:

Narrative Description Data

Matrix:

Not Specified

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

The Los Angeles River Trash TMDL was completed by the Regional Board on September 19, 2001 (USEPA, 2002) to address impairments caused by trash. However, on July 19, 2006 the State Board rescinded approval of this TMDL and remanded it back to the Regional Board based on court ruling City of Arcadia v. State Water Resources Control Board (D043877).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

QA Info Missing

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 99749, Benthic Community Effects	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

2510

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Not Specified

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Unspecified--This LOE is a placeholder to support a listing decision made by USEPA for 2006.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

QA Info Missing

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 99749, Benthic Community Effects	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

85997

Pollutant:

Copper

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:

Eight of the 93 samples exceeded the hardness adjusted criteria.

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion 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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The River was sampled between Figueroa St. and Riverside Dr.

Temporal Representation:

One sample was collected in 2007, two samples was collected in 2008, three samples were collected in 2009, and one sample was collected in 2010.

Environmental Conditions:

There was no special environmental condition reported.

QAPP Information:

QAPP Information Reference(s):


DECISION ID	100591	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	DDD (Dichlorodiphenyldichloroethane)
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 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. 1 line of evidence is available in the administrative record to assess this pollutant. 0 of 23 samples exceed the GUIDELINE. 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 23 samples exceed the GUIDELINE and this sample size is INSUFFICIENT to determine beneficial use support, with the power and confidence of the Listing Policy. There is not an associated sediment toxicity data as required by Section 3.6 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 100591, DDD (Dichlorodiphenyldichloroethane)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

85999

Pollutant:

DDD (Dichlorodiphenyldichloroethane)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

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 twenty three samples exceeded the evaluation guideline.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for sum of DDD is 28.0 ug/Kg dry weight.

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Sediment samples were collected at station LA River R4, LA River R5 and LA River R7.

Temporal Representation:

Samples were collected in 2006 on February 7 and August 2, and in 2007 on February 7.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):


DECISION ID	96144	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	DDE (Dichlorodiphenyldichloroethylene)
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 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. 1 line of evidence is available in the administrative record to assess this pollutant. 0 of 23 samples exceed the GUIDELINE. 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 23 samples exceed the GUIDELINE and this sample size is INSUFFICIENT to determine beneficial use support, with the power and confidence of the Listing Policy. There is not an associated sediment toxicity data as required by Section 3.6 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 96144, DDE (Dichlorodiphenyldichloroethylene)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

86000

Pollutant:

DDE (Dichlorodiphenyldichloroethylene)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

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 twenty three samples exceeded the evaluation guideline.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for sum of DDE is 31.3 ug/Kg dry weight.

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Sediment samples were collected at station LA River R4, LA River R5 and LA River R7.

Temporal Representation:

Samples were collected in 2006 on February 7 and August 2, and in 2007 on February 7.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):


DECISION ID	96145	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

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 is necessary to assess listing status. 1 line of evidence is available in the administrative record to assess this pollutant. 0 of 23 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 23 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 96145, Endosulfan	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

86003

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 23 samples exceeded the water quality criteria/objective.

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 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:

Toxic Rule criteria fresh aquatic life protection continuous concentration (4-day average)is 0.056 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 23 samples were collected at sampling locations, LA RIVER R-4 (9 samples), LA River R-5 (5 samples) and LA River R-7 (9 samples).

Temporal Representation:

Environmental Conditions:

There was no special environmental conditions reported.

QAPP Information:

QAPP Information Reference(s):


DECISION ID	100454	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	Toxicity
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Sources:	A Source Unknown
Expected TMDL Completion Date:	2027
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.6 of the Listing Policy. Under section 3.6 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. 29 of 75 samples exceeded the GUIDELINE. 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. 29 of 75 samples exceeded the GUIDELINE 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:	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 100454, Toxicity	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

85936

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:

Data Reference:

Data from Los Angeles-Glendale Water Reclamation Plant NPDES Permit no. CA0053953, Jul. 2005-Jun. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Water Quality Control Plan Los Angeles Region R4 Basin Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at Los Angeles River R4, R5 and R7.

Temporal Representation:

The samples were collected every three months from November 2005 to May 2010.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):


DECISION ID	68871	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	Nutrients (Algae)
Final Listing Decision:	List on 303(d) list (being addressed by USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision:	List on 303(d) list (being addressed by USEPA approved TMDL)(2016)
Revision Status	Original
Sources:	Nonpoint Source \| Point Source
TMDL Name:	Los Angeles River Nitrogen (11)
TMDL Project Code:	229
Date TMDL Approved by USEPA:	03/18/2004
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for listing under section 2.2 of the Listing Policy. Under this section of the Policy, a minimum of one line of evidence is needed to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. A TMDL has been developed and approved by USEPA and an approved implementation plan is expected to result in attainment of the standard. The Los Angeles River Nitrogen TMDL was approved by RWQCB on August 19, 2003 and subsequently approved by USEPA on March 18, 2004. This TMDL will address this water body condition. 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 in the Water Quality Limited Segments Being Addressed portion of the section 303(d) list.

Regional Board Decision Recommendation:	This is a decision previously approved by the State Water Resources Control Board and the USEPA. No new data were assessed by the Regional Board for the current cycle. The decision has not changed.

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 68871, Nutrients (Algae)	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

2504

Pollutant:

Nutrients (Algae)

LOE Subgroup:

Pollutant-Water

Matrix:

Not Specified

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

QA Info Missing

QAPP Information Reference(s):


DECISION ID	68157	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

Pollutant:	Trash
Final Listing Decision:	List on 303(d) list (being addressed by USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision:	List on 303(d) list (being addressed by USEPA approved TMDL)(2016)
Revision Status	Original
Sources:	Nonpoint Source \| Surface Runoff \| Urban Runoff/Storm Sewers
TMDL Name:	Los Angeles River Trash (12)
TMDL Project Code:	365
Date TMDL Approved by USEPA:	07/24/2008
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for removal on the section 303(d) list under sections 2.2 of the Listing Policy. Under 2.2 of the Policy, a minimum of one line of evidence is needed to assess listing status. Two lines of evidence are 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 removing this water segment-pollutant combination from the section 303(d) list. There is sufficient justification to place it in the Being Addressed portion of the 303(d) list because a TMDL has been completed and adopted by the Los Angeles RWQCB and approved by USEPA, and is expected to result in attainment of the standard.

Regional Board Decision Recommendation:	This is a decision previously approved by the State Water Resources Control Board and the USEPA. No new data were assessed by the Regional Board for the current cycle. The decision has not changed.

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 68157, Trash	Region 4
Los Angeles River Reach 3 (Figueroa St. to Riverside Dr.)

LOE ID:

2508

Pollutant:

Trash

LOE Subgroup:

Narrative Description Data

Matrix:

Not Specified

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Data Reference: