2020 Watershed Sanitary Survey This page intentionally left blank 2 2020 Watershed Sanitary Survey (CDPH SYSTEM NUMBER 37-10020) MARCH 1, 2021 Public Utilities Department Contributing Agencies California Regional Water Quality Control Board, San Diego Region California Water Boards, State Water Resources Control Board County of San Diego, Department of Environmental Health County of San Diego, Department of Parks and Recreation National Oceanic and Atmospheric Association San Diego County Water Authority San Diego History Center San Diego Natural History Museum State of California, Department of Forestry and Fire Protection State of California, Department of Toxic Substances Control State of California, Department of Water Resources, California Data Exchange Center United States Department of Agriculture Forest Service, Cleveland National Forest United States Census Bureau United States Department of the Interior, Bureau of Land Management United States Geological Survey Cover Photographs Barrett Watershed, Surface Runoff Morena Reservoir Sutherland Dam and Spillway Alvarado Water Treatment Plant 3 This page intentionally left blank 4 TABLE OF CONTENTS Page Title Page .............................................................................................................................................................. 3 Table of Contents ................................................................................................................................................ 5 List of Figures & Tables ...................................................................................................................................... 9 Abbreviations ....................................................................................................................................................... 11 Summary .............................................................................................................................................................. 15 Review of Recommendations ..................................................................................................................... 24 Watershed Areas Under CSD Jurisdiction .......................................................................................... 24 Watershed Areas Not Under CSD Jurisdiction ................................................................................... 24 Chapter 1: Introduction ...................................................................................................................................... 27 1.1 Requirements of the Watershed Sanitary Survey (WSS) ......................................................................... 27 1.2 Objectives of the Watershed Sanitary Survey............................................................................................ 27 1.3 Conduct of the Watershed Sanitary Survey .............................................................................................. 27 1.4 Laws and Regulations .................................................................................................................................. 27 Federal Water Pollution Control Act / Clean Water Act (CWA) ............................................................... 28 Porter-Cologne Water Quality Control Act (California Water Code) ...................................................... 28 State Water Resources Control Board Antidegradation Policy .............................................................. 28 Federal Safe Drinking Water Act (FSDWA) ................................................................................................ 29 California Safe Drinking Water Act (CSDWA) ............................................................................................ 29 Federal Surface Water Treatment Rules (FSWTRs) .................................................................................. 29 California Surface Water Treatment Rules (CSWTRs) .............................................................................. 29 Endangered Species Act (ESA) .................................................................................................................... 30 1.5 Basic Water Rights ........................................................................................................................................ 30 Surface Water ............................................................................................................................................... 31 Riparian Rights ....................................................................................................................................... 31 Appropriative Rights ............................................................................................................................. 31 The Water Commission Act .................................................................................................................. 31 Public Trust Doctrine ............................................................................................................................ 31 Pueblo Water Rights .............................................................................................................................. 31 Adjudicated Rights ................................................................................................................................ 31 Reserved Rights ..................................................................................................................................... 31 Contractual Entitlements ..................................................................................................................... 31 Groundwater ................................................................................................................................................ 32 1.6 Historical Background of Water Development ......................................................................................... 32 Chapter 2: Description of the Source Water System ...................................................................................... 37 2.1 Water Sources ............................................................................................................................................... 37 Groundwater ................................................................................................................................................ 38 Imported Water ............................................................................................................................................ 38 Local Surface Water ..................................................................................................................................... 38 2.2 Source Water Reservoirs ............................................................................................................................. 40 San Diego River System ............................................................................................................................... 42 Murray Reservoir ................................................................................................................................... 42 San Vicente Reservoir ........................................................................................................................... 43 5 El Capitan Reservoir .............................................................................................................................. 43 Cuyamaca Reservoir ............................................................................................................................. 43 Sutherland Reservoir ............................................................................................................................ 44 Otay-Cottonwood System .................................................................................................................................. 45 Otay Reservoir ....................................................................................................................................... 45 Upper Otay Reservoir ........................................................................................................................... 45 Barrett Reservoir ................................................................................................................................... 46 Morena Reservoir .................................................................................................................................. 46 Miramar System ........................................................................................................................................... 47 Miramar Reservoir ................................................................................................................................ 47 Hodges System ............................................................................................................................................. 47 Hodges Reservoir .................................................................................................................................. 47 Chapter 3: Physical and Hydrogeological Description of the Local Watersheds ........................................ 49 3.1 Geology .......................................................................................................................................................... 53 Geology within the Local Source