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

Supporting Information

Regional Board 4 - Los Angeles Region

Water Body Name:	Torrance Beach
Water Body ID:	CAX4051200019990924082657
Water Body Type:	Coastal & Bay Shoreline


DECISION ID	150337	Region 4
Torrance Beach

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:	Nonpoint Source
TMDL Name:	Santa Monica Bay Beach Closures/Coliform/Bacteria Indicators (48)
TMDL Project Code:	392
Date TMDL Approved by USEPA:	06/19/2003
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 4.3 of the Listing Policy. Under section 4.3 of the Policy, a minimum of one line of evidence is needed to assess listing status. 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. 5 of 12 samples exceeded the geometric mean for Enterococcus and 7 of 9 samples exceeded the geometric mean for fecal coliform and these exceed the allowable frequency listed in Table 4.2 of the Listing Policy. 4. The Santa Monica Bay Bacteria Dry Weather TMDL was approved by RWQCB on January 24, 2002 and subsequently approved by USEPA. The Santa Monica Bay Bacteria Wet Weather TMDL was approved by RWQCB on December 12, 2004 and approved by USEPA on June 19, 2003. 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 150337, Indicator Bacteria	Region 4
Torrance Beach

LOE ID:

302028

Pollutant:

Fecal Coliform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

SSM

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 SMBBB Coordinated Shoreline Monitoring Program data for Torrance Beach to determine beneficial use support and the results are as follows: 6 of the 29 samples exceeded the water quality threshold for Coliform, Fecal. The water quality threshold is based on a Single Sample Maximum (SSM) value that is calculated daily.

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 bacteria water quality objective to protect the REC-1 beneficial use in ocean waters applies a single sample maximum of fecal coliform, not to exceed 400 per 100 mL. (Ocean Plan 2019)

Objective/Criterion Reference:

SWRCB. 2005. Water Quality Control Plan, Ocean Waters of California (Ocean Plan). California Environmental Protection Agency, State Water Resources Control Board. February 2, 2019

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s), station(s): SMB-6-6 (SMB-6-6).

Temporal Representation:

The samples were collected between the days of 2015-07-13 and 2016-06-27 .

Environmental Conditions:

QAPP Information:

The technical Steering committee co-chairs city and county of los angeles co-chairs city and county of los angeles. 2004. SANTA MONICA BAY BEACHES BACTERIAL TMDLs COORDINATED SHORELINE MONITORING PLAN.

QAPP Information Reference(s):

SANTA MONICA BAY BEACHES BACTERIAL TMDLs COORDINATED SHORELINE MONITORING PLAN

Line of Evidence (LOE) for Decision ID 150337, Indicator Bacteria	Region 4
Torrance Beach

LOE ID:

303059

Pollutant:

Fecal Coliform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

SSM

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 Torrance Beach to determine beneficial use support and the results are as follows: 4 of the 55 samples exceeded the water quality threshold for Coliform, Fecal. The water quality threshold is based on a Single Sample Maximum (SSM) value that is calculated daily.

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 in ocean waters applies a single sample maximum of fecal coliform, not to exceed 400 per 100 mL. (Ocean Plan 2019)

Objective/Criterion Reference:

SWRCB. 2005. Water Quality Control Plan, Ocean Waters of California (Ocean Plan). California Environmental Protection Agency, State Water Resources Control Board. February 2, 2019

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s), station(s): SMB-6-6 (SMB-6-6).

Temporal Representation:

The samples were collected between the days of 2016-03-20 and 2018-12-31 .

Environmental Conditions:

QAPP Information:

Municipal Separate Storm Sewer System (MS4)

QAPP Information Reference(s):

Municipal Separate Storm Sewer System (MS4)

Line of Evidence (LOE) for Decision ID 150337, Indicator Bacteria	Region 4
Torrance Beach

LOE ID:

303098

Pollutant:

Enterococcus

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

STV

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed LA County MS4 data for Torrance Beach to determine beneficial use support and the results are as follows: 4 of the 18 samples exceeded the Statistical Threshold Value (STV) water quality threshold for Enterococcus. The STV is based on a 10% exceedance rate that is calculated monthly.

Data Reference:

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 in ocean waters, applies a Statistical Threshold Value to enterococcus of 110 cfu/100 mL, not to be exceeded by more than 10 percent of samples collected within in a calendar month. (Ocean Plan 2019)

Objective/Criterion Reference:

SWRCB. 2005. Water Quality Control Plan, Ocean Waters of California (Ocean Plan). California Environmental Protection Agency, State Water Resources Control Board. February 2, 2019

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s), station(s): SMB-6-6 (SMB-6-6).

Temporal Representation:

The samples were collected between the days of 2016-07-25 and 2018-12-31 .

Environmental Conditions:

QAPP Information:

Municipal Separate Storm Sewer System (MS4)

QAPP Information Reference(s):

Municipal Separate Storm Sewer System (MS4)

Line of Evidence (LOE) for Decision ID 150337, Indicator Bacteria	Region 4
Torrance Beach

LOE ID:

302160

Pollutant:

Enterococcus

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

GeoMean

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 SMBBB Coordinated Shoreline Monitoring Program data for Torrance Beach to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the geomean water quality threshold for Enterococcus. This is a six week rolling geomean that is calculated weekly.

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 bacteria water quality objective to protect the REC-1 beneficial in ocean waters applies a six-week rolling geomean to enterococcus, not to exceed 30 cfu/100mL. (Ocean Plan 2019)

Objective/Criterion Reference:

SWRCB. 2005. Water Quality Control Plan, Ocean Waters of California (Ocean Plan). California Environmental Protection Agency, State Water Resources Control Board. February 2, 2019

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s), station(s): SMB-6-6 (SMB-6-6).

Temporal Representation:

The samples were collected between the days of 2015-07-27 and 2016-03-07 .

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

SANTA MONICA BAY BEACHES BACTERIAL TMDLs COORDINATED SHORELINE MONITORING PLAN

Line of Evidence (LOE) for Decision ID 150337, Indicator Bacteria	Region 4
Torrance Beach

LOE ID:

3611

Pollutant:

Coliform Bacteria

LOE Subgroup:

Pollutant-Water

Matrix:

Not Specified

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.

Data Reference:

Placeholder reference 2006 303(d)

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 150337, Indicator Bacteria	Region 4
Torrance Beach

LOE ID:

302172

Pollutant:

Enterococcus

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

STV

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SMBBB Coordinated Shoreline Monitoring Program data for Torrance Beach to determine beneficial use support and the results are as follows: 0 of the 7 samples exceeded the Statistical Threshold Value (STV) water quality threshold for Enterococcus. The STV is based on a 10% exceedance rate that is calculated monthly.

Data Reference:

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:

SWRCB. 2005. Water Quality Control Plan, Ocean Waters of California (Ocean Plan). California Environmental Protection Agency, State Water Resources Control Board. February 2, 2019

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s), station(s): SMB-6-6 (SMB-6-6).

Temporal Representation:

The samples were collected between the days of 2015-07-27 and 2016-03-07 .

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

SANTA MONICA BAY BEACHES BACTERIAL TMDLs COORDINATED SHORELINE MONITORING PLAN

Line of Evidence (LOE) for Decision ID 150337, Indicator Bacteria	Region 4
Torrance Beach

LOE ID:

303027

Pollutant:

Enterococcus

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

GeoMean

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 Torrance Beach to determine beneficial use support and the results are as follows: 5 of the 8 samples exceeded the geomean water quality threshold for Enterococcus. This is a six week rolling geomean that is calculated weekly.

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 in ocean waters applies a six-week rolling geomean to enterococcus, not to exceed 30 cfu/100mL. (Ocean Plan 2019)

Objective/Criterion Reference:

SWRCB. 2005. Water Quality Control Plan, Ocean Waters of California (Ocean Plan). California Environmental Protection Agency, State Water Resources Control Board. February 2, 2019

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s), station(s): SMB-6-6 (SMB-6-6).

Temporal Representation:

The samples were collected between the days of 2016-07-25 and 2018-12-31 .

Environmental Conditions:

QAPP Information:

Municipal Separate Storm Sewer System (MS4)

QAPP Information Reference(s):

Municipal Separate Storm Sewer System (MS4)

Line of Evidence (LOE) for Decision ID 150337, Indicator Bacteria	Region 4
Torrance Beach

LOE ID:

302139

Pollutant:

Fecal Coliform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

GeoMean

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 SMBBB Coordinated Shoreline Monitoring Program data for Torrance Beach to determine beneficial use support and the results are as follows: 7 of the 9 samples exceeded the water quality threshold for Coliform, Fecal. The water quality threshold is based on a 30-Day rolling geomean.

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 bacteria water quality objective to protect the REC-1 beneficial use in ocean waters applies a 30 day geometric mean of fecal coliform based on the five most recent samples at each site, not to exceed 200 per 100 mL. (Ocean Plan 2019)

Objective/Criterion Reference:

SWRCB. 2005. Water Quality Control Plan, Ocean Waters of California (Ocean Plan). California Environmental Protection Agency, State Water Resources Control Board. February 2, 2019

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s), station(s): SMB-6-6 (SMB-6-6).

Temporal Representation:

The samples were collected between the days of 2015-07-13 and 2016-06-27 .

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

SANTA MONICA BAY BEACHES BACTERIAL TMDLs COORDINATED SHORELINE MONITORING PLAN


DECISION ID	70681	Region 4
Torrance Beach

Pollutant:	Beach Closures
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. The original line of evidence supporting the listing does not identify a pollutant but rather, a condition caused by a pollutant(s) (beach closures). The dry weather TMDL was approved by the RWQCB on 1/24/02, and the wet weather TMDL was approved on 12/12/04, and subsequently approved by USEPA on 6/19/03. These TMDLs are expected to 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 these listing from the 303(d) list because beach closures are not pollutants. Beach closure information should not be placed on the section 303(d) list because it is not a pollutant or toxicity (section 2 of the Listing Policy).

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 70681, Beach Closures	Region 4
Torrance Beach

LOE ID:

3610

Pollutant:

Beach Closures

LOE Subgroup:

Narrative Description Data

Matrix:

Not Specified

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

A TMDL and implementation plan has been approved for this water segment-pollutant combination. The Santa Monica Bay Bacteria Dry Weather TMDL was approved by RWQCB on January 24, 2002 and subsequently approved by USEPA. The Santa Monica Bay Bacteria Wet Weather TMDL was approved by RWQCB on December 12, 2002 and approved by USEPA on June 19, 2003.

Data Reference:

Placeholder reference 2006 303(d)

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):