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Water Quality Standards Regulations: California

Recent Proposed Rules

Proposed Rule - Numeric Criterion for Selenium for Fresh Waters in California

EPA is proposing to establish a federal CWA selenium water quality criterion for certain California fresh waters that protects aquatic life and aquatic-dependent wildlife. EPA's proposed rule does not apply to California waters where site-specific selenium criteria have been adopted, nor does it apply to California waters with selenium criteria promulgated in the National Toxics Rule.

Proposed Rule - Numeric Criteria for Selenium for the San Francisco Bay and Delta, State of California

EPA is proposing to revise the current federal Clean Water Act (CWA) selenium water quality criteria applicable to the salt and estuarine waters of San Francisco Bay and Delta to ensure that the criteria are set at levels that protect aquatic life and aquatic-dependent wildlife, including federally listed threatened and endangered species.

Presented below are water quality standards in effect for Clean Water Act (CWA) purposes for this state.

EPA is posting these standards as a convenience to users and has made a reasonable effort to assure their accuracy. Also, for each document listed under "State Standards in Effect for CWA Purposes", EPA has made a reasonable effort to identify parts of the standards that are disapproved or are otherwise not in effect for CWA purposes.


State Standards in Effect for CWA Purposes

State Water Resources Control Board

The State Water Resources Control Board (State Water Board) was created by the California State Legislature in 1967. The joint authority of water allocation and water quality protection enables the State Water Board to provide comprehensive protection for California's waters.

Regional Water Quality Control Boards

There are nine Regional Water Quality Control Boards (Regional Boards) with the mission to develop and enforce water quality objectives and implementation plans that will best protect the beneficial uses of the State’s waters, recognizing local differences in climate, topography, geology and hydrology. California’s water quality standards are embodied in Basin Plans administered by these Regional Water Quality Control Boards and in several statewide Plans and Policies administered by the State Water Resources Control Board. Amendments to a Basin Plan, prepared by the Regional Boards, are reviewed by the State Board and the State’s Office of Administrative Law (OAL). Once approved, the amendments are submitted to EPA for final approval.

On this page:


Statewide Plans

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Statewide Policies

Basin Plans with listed water quality standards amendments for the nine Regional Water Quality Control Boards are included under the other tabs on this webpage. Please note that the Basin Plans also include provisions outside the scope of water quality standards. The dates provided generally reflect the most recent effective date for the water quality standards portions of the plans.

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Regional Water Quality Control Board 2 (San Francisco Bay Region)

Amendments to the Water Quality Control Plan for the San Francisco Bay Region
Effective Date Description
07-02-19 [See Approved revisions to site-specific water quality objectives for dissolved oxygen (DO) in Suisun Marsh and non-substantive changes to the Water Quality Control Plan ]

Regional Water Quality Control Board 3 (Central Coast)


Regional Water Quality Control Board 4 (Los Angeles)

Amendments to the Water Quality Control Plan for the Los Angeles Region
Effective Date Description
01-27-97 [See Amendment to the Water Quality Control Plan for the Los Angeles Region (PDF)]
09-25-02 [See Update to bacteria objectives for waterbodies designated for Water Contact Recreation (PDF)]
06-19-03 [See Update to ammonia water quality objectives and implementation procedures for inland surface waters, enclosed bays, and estuaries which are characteristic of freshwater and support aquatic life (PDF)]
06-19-03 [See Incorporates (1) implementation provisions for the bacteria objectives; (2) the Santa Monica Bay Beaches wet-weather TMDL; and (3) the Santa Monica Bay Beaches dry-weather TMDL, Resolution 2002-022 (PDF)]
02-10-04 [See Amendment for the coastal watersheds of Los Angeles and Ventura Counties that incorporates language authorizing the inclusion of compliance schedules in NPDES permits, Resolution 2003-001 (PDF)]
02-17-06 [See Update to Beneficial Uses (PDF)]

These amendments incorporate 1) the removal of the potential REC-1 beneficial use associated with the Swimmable Goal - as expressed in the federal Clean Water Act Section 101(a)(2) - for "Ballona Creek," replace the potential REC-1 beneficial use for "Ballon Creek to Estuary" with an Existing Limited REC-1 Use, and 2) add bacteria objectives to prtect the new limited REC-1 use.

[See Amended Beneficial Use Table 2.1 (PDF)]
02-16-07 [See Amendment for revised early life stage implementation provision for inland surface water ammonia objectives for freshwaters, Resolution 2005-014 (PDF)]
03-30-09 [See Amendment incorporating site-specific objectives for ammonia, Resolution 2007-005 (PDF)]
05-18-09 [See Amendment subdividing Santa Clara River reach 4 into two Reaches, 4A and 4B, Resolution R4-2007-018 (PDF)]
04-28-15 [See Attachment B to: Revision of the TMDL for Chloride in the Upper Santa Clara River, Resolution No. R4-2014-010 (PDF)]
12-12-16 [See Attachment A to: Revision of Lead Water Quality Objectives for Los Angeles River and Tributaries, Resolution No. R15-004 ]
05-11-17 [See Attachment A to: Implementation Plan for the Total Maximum Daily Loads for Metals and Selenium in the San Gabriel River and Impaired Tributaries, Resolution No. R13-004 ]

Regional Water Quality Control Board 5 (Central Valley)

Amendments to the Water Quality Control Plans for Central Valley (Board 5)
Effective Date Description
07-08-16 [See Variances from Surface Water Quality Standards for Point Source Dischargers, Variance Program for Salinity, and Exception from Implementation of Water Quality Objective for Salinity, Resolution R5-2014-0074 ]
Amendments to the Water Quality Control Plan for the Tulare Lake Basin
Effective Date Description
01-06-04 [See Modification of Language, Resolution No. R5-2014-0038 (PDF)]
09-23-15 [See Modification of language addressing antidegradation policies, Resolution R5-2002-0177 (PDF)]
Amendments to the Water Quality Control Plan for the Sacramento and San Joaquin River Basins
Effective Date Description
09-26-03 [See Establish a program for the control of mercury in Clear Lake, Resolution R5-2002-0207 (PDF)]
10-15-03 [See Establish site-specific objectives for pH and turbidity for Deer Creek in Sacramento and El Dorado counties, Resolution R5-2002-0127 (PDF)]
01-06-04 [See Modifies language addressing antidegradation policies, Resolution R5-2002-0151 (PDF)]
08-11-04 [See Diazinon objectives for Sacramento and Feather Rivers, Resolution R5-2003-0148 (PDF)]
05-01-06 [See Deer Creek temperature site-specific objectives, Resolution R5-2003-0006 (PDF)]
05-01-06 [See Correction to Deer Creek temperature site-specific objectives, Resolution R5-2005-0119 (PDF)]
08-07-06 [See Redesignation of Old Alamo Creek, Resolution R5-2005-0053 (PDF)]
12-20-06 [See Diazinon and chlorpyrifos objectives for Lower San Joaquin River, Resolution R5-2005-0138 (PDF)]
02-06-07 [See Designate commercial and sport fishing (COMM) use and establishing site-specific methylmercury in fish tissue criteria, Resolution R5-2005-0146 (PDF)]
10-10-07 [See Diazinon and chlorpyrifos objectives for the Sacramento/San Joaquin Delta, Resolution R5-2006-0061 (PDF)]
03-12-08 [See Establish compliance schedules for salt and boron wasteload allocations for a TMDL in the Lower San Joaquin River, Resolution R5-2004-0108 (PDF)]
08-11-08 [See Diazinon and chlopyrifos objectives for Sacramento and Feather Rivers, Resolution R5-2007-0034 (PDF)]
07-07-09 [See Revise pH and Turbidity Water Quality Objectives for All Waters in the Basin Plan, Resolution R5-2007-0136 (PDF)]
09-04-09 [See Remove Beneficial Uses and Establish Water Quality Objectives in Sulphur Creek, Colusa County, Resolution R5-2007-0021 (PDF)]
10-20-11 [See Control of Methylmercury and Total Mercury in the Sacramento-San Joaquin Delta Estuary, Resolution R5-2010-0043 (PDF)]
04-09-13 [See Water Quality Objectives for Chloroform, Chlorodibromomethane, and Dichlorobromomethane for New Alamo and Ulatis Creeks, Solano County, and Permit Implementation Provisions, Resolution R5-2010-0047 (PDF)]
11-20-14 [See Establishment of a Drinking Water Policy for Surface Waters of the Sacramento and San Joaquin River Basins Delta and Upstream Tributaries (PDF)]
09-23-15 [See Modification of Language, Resolution No. R5-2014-0037 (PDF)]
04-21-16 [See Removal of the Municipal and Domestic Supply (MUN) Beneficial Use in Twelve Constructed and/or Modified Water Bodies in the Sacramento River Basin Resolution R5-2015-0055 ]
08-16-17 [See Control of Diazinon and Chlorpyrifos Discharges, Resolution R5-2014-0041 ]
12-17-18 [See Electrical Conductivity in the Lower San Joaquin River Water Quality Standards Amendments ]

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Regional Water Quality Control Board 7 (Colorado River Basin)


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Regional Water Quality Control Board 9 (San Diego)


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