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Water Quality Control Plan, Colorado River Basin

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Water Quality Control Plan, Colorado River Basin Presented below are water quality standards that are in effect for Clean Water Act purposes. EPA is posting these standards as a convenience to users and has made a reasonable effort to assure their accuracy. Additionally, EPA has made a reasonable effort to identify parts of the standards that are not approved, disapproved, or are otherwise not in effect for Clean Water Act purposes. EPA has approved all provisions in this document that are water quality standards, and those provisions are in effect for Clean Water Act purposes. Note that not all provisions of the attached document are water quality standards that require EPA review and approval. WATER QUALITY CONTROL PLAN COLORADO RIVER BASIN- REGION 7 Includes Amendments Adopted by the Regional Board through August 2017 CALIFORNIA REGIONAL WATER QUALITY CONTROL BOARD STATE WATER RESOURCES CONTROL BOARD FOREWORD On November 17, 1993 the Regional Board adopted Resolution No. 93-145 which approved this 1993 Basin Plan. This Basin Plan was subsequently approved by the State Water Resources Control Board on February 17, 1994 (Resolution No. 94-18). The California Office of Administrative Law approved the adoption of the 1993 Basin Plan on August 3, 1994. This Basin Plan now supersedes the previous (1991) Basin Plan. This Basin Plan was prepared by the California Regional Water Quality Control Board, Colorado River Basin Region, in accordance with criteria contained in the California Porter-Cologne Water Quality Control Act, the Federal Clean Water Act, and other pertinent state and federal rules and regulations. The intent of this plan is to provide definitive guidelines, and give direction to the full scope of Regional Board activities that serve to optimize the beneficial uses of state waters within the Colorado River Basin Region of California by preserving and protecting the quality of these waters. This plan is also subject to review by the United States Environmental Protection Agency (EPA). The plan is in itself not a final statement on regional water quality planning, but is subject to continuous review, and update as necessary. Updated sections of the plan may appear as periodic Basin Plan amendments, which are also subject to approval by the State Water Resources Control Board and the Office of Administrative Law. This Basin Plan includes amendments adopted by the Regional Board through August 2017. TABLE OF CONTENTS CHAPTER 1 - INTRODUCTION .................................................................................. 1 I. THE REGIONAL BOARD ................................................................................................. 1 II. FUNCTION OF THE BASIN PLAN ................................................................................... 1 III. LEGAL BASIS AND AUTHORITY .................................................................................... 2 FEDERAL REQUIREMENTS .................................................................................... 2 CALIFORNIA STATUTORY AND ADMINISTRATIVE LAWS ....................................... 3 OTHER PLANNING AGENCIES ................................................................................ 5 IV. THE PLANNING PROCESS ............................................................................................ 6 BASIN PLAN AMENDMENT PROCESS.................................................................... 6 TRIENNIAL REVIEW PROCESS ................................................................................ 7 V. THE COLORADO RIVER BASIN REGION ........................................................................ 8 GEOGRAPHICAL SETTING ..................................................................................... 8 GEOLOGY .............................................................................................................. 8 MAJOR HYDROLOGIC FEATURES .......................................................................... 9 CLIMATE ............................................................................................................. 10 FISH AND WILDLIFE RESOURCES ......................................................................... 10 VI. PLANNING AREAS ..................................................................................................... 11 LUCERNE VALLEY PLANNING AREA .................................................................... 11 HAYFIELD PLANNING AREA................................................................................. 12 COACHELLA VALLEY PLANNING AREA ................................................................ 14 ANZA-BORREGO PLANNING AREA ..................................................................... 15 IMPERIAL VALLEY PLANNING AREA .................................................................... 16 SALTON SEA PLANNING AREA ............................................................................. 16 EAST COLORADO RIVER BASIN PLANNING AREA ............................................... 17 CHAPTER 2 - BENEFICIAL USES ............................................................................. 1 I. PAST OR HISTORICAL BENEFICIAL USES ........................................................................ 1 II. PRESENT BENEFICIAL USES .......................................................................................... 2 III. POTENTIAL BENEFICIAL USES ..................................................................................... 3 IV. SOURCES OF DRINKING WATER POLICY ..................................................................... 3 SURFACE AND GROUND WATERS WHERE: .......................................................... 3 SURFACE WATERS WHERE: ................................................................................... 4 GROUND WATERS WHERE: .................................................................................. 4 REGIONAL BOARD AUTHORITY TO AMEND USE DESIGNATIONS: ........................ 4 CHAPTER 3 - WATER QUALITY OBJECTIVES ........................................................ 1 I. GENERAL OBJECTIVES ................................................................................................... 1 II. GENERAL SURFACE WATER OBJECTIVES ..................................................................... 1 AESTHETIC QUALITIES .......................................................................................... 2 TAINTING SUBSTANCES ........................................................................................ 2 TOXICITY .............................................................................................................. 2 TEMPERATURE ..................................................................................................... 2 pH .......................................................................................................................... 2 DISSOLVED OXYGEN .............................................................................................. 3 SUSPENDED SOLIDS AND SETTLEABLE SOLIDS ..................................................... 3 TOTAL DISSOLVED SOLIDS .................................................................................... 3 BACTERIA ............................................................................................................... 3 BIOSTIMULATORY SUBSTANCES ............................................................................ 4 SEDIMENT ............................................................................................................. 4 TURBIDITY ............................................................................................................. 4 RADIOACTIVITY .................................................................................................... 4 CHEMICAL CONSTITUENTS ................................................................................... 5 PESTICIDE WASTES ............................................................................................... 6 III. SPECIFIC SURFACE WATER OBJECTIVES ...................................................................... 6 COLORADO RIVER ................................................................................................. 6 NEW RIVER ........................................................................................................... 7 SALTON SEA .......................................................................................................... 8 IRRIGATION SUPPLY CANALS ................................................................................ 9 COACHELLA VALLEY STORM WATER CHANNEL .................................................... 9 IV. GROUND WATER OBJECTIVES .................................................................................. 10 TASTE AND ODORS ............................................................................................. 10 BACTERIOLOGICAL QUALITY ............................................................................... 10 CHEMICAL AND PHYSICAL QUALITY ................................................................... 10 BRINES ................................................................................................................ 10 RADIOACTIVITY ................................................................................................... 11 GROUND WATER OVERDRAFT ............................................................................ 11 CHAPTER 4 - IMPLEMENTATION ............................................................................. 1 I. INTRODUCTION ...........................................................................................................
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