Tuolumne-Stanislaus Integrated Regional Water Management Plan August 2013 Updated Fall 2017 Table of Contents Executive Summary ................................................................................................................ ES-1 Section 1: Introduction ............................................................................... 1-1 1.1 Introduction ......................................................................................... 1-1 1.2 Background ........................................................................................ 1-1 1.2.1 Regional Features ................................................................... 1-1 1.2.2 Primary Focal Points for the IRWM Plan ................................. 1-1 1.2.3 Formation of the IRWM Region ............................................... 1-4 1.3 Governance ........................................................................................ 1-5 1.3.1 Regional Water Management Group (RWMG) ....................... 1-5 1.3.2 Planning Grant Committee (PGC) ........................................... 1-7 1.4 Stakeholder Coordination and Outreach ............................................ 1-7 1.4.1 Overview of the Stakeholder Coordination and Outreach Process ................................................................................... 1-7 1.4.2 Stakeholders ........................................................................... 1-8 1.4.2.1 Municipal and County Governments ................... 1-10 1.4.2.2 Wholesale and Retail Water Purveyors, Wastewater Agencies, and Similar Special Districts ............................................................... 1-10 1.4.2.3 State and Federal Regulatory Resource Agencies ............................................................. 1-10 1.4.2.4 Environmental Community .................................. 1-10 1.4.2.5 Tribal Community ................................................ 1-10 1.4.2.6 Disadvantaged Community ................................. 1-10 1.4.2.7 Others ................................................................. 1-11 1.4.3 Community Outreach Overview ............................................ 1-11 1.4.3.1 Disadvantaged Communities .............................. 1-12 1.4.3.2 Tribal Outreach ................................................... 1-12 1.4.4 Neighboring IRWM Regions .................................................. 1-13 1.5 Plan Development ............................................................................ 1-13 1.5.1 Overview ............................................................................... 1-13 1.5.2 Subcommittees ...................................................................... 1-15 1.5.3 Plan Organization .................................................................. 1-16 1.6 Plan Adoption ................................................................................... 1-17 Section 2: Region Description .................................................................... 2-1 2.1 Introduction ......................................................................................... 2-1 2.2 Region Overview ................................................................................ 2-1 2.2.1 History of Water Development in the Region .......................... 2-4 2.2.1.1 Early History .......................................................... 2-4 2.2.1.2 19th Century ........................................................... 2-4 2.2.1.3 Development of Water Supply Infrastructure ........ 2-4 Tuolumne-Stanislaus IRWM Plan, August 2013 i Table of Contents Table of Contents (cont'd) 2.2.1.4 20th Century and Development of Water Systems ................................................................ 2-5 2.3 Social and Cultural Makeup ................................................................ 2-6 2.3.1 Population ............................................................................... 2-6 2.3.2 Socioeconomic Conditions ...................................................... 2-7 2.3.3 Disadvantaged Communities .................................................. 2-8 2.3.4 Native American Tribes ........................................................... 2-9 2.3.5 Water-Dependent Recreation .................................................. 2-9 2.4 Climate ............................................................................................. 2-12 2.5 Land Use .......................................................................................... 2-14 2.6 Jurisdictional Boundaries .................................................................. 2-16 2.7 Watersheds ...................................................................................... 2-21 2.7.1 Upper Tuolumne River Watershed ........................................ 2-22 2.7.2 Upper Stanislaus River Watershed ....................................... 2-25 2.7.3 Upper Rock Creek-French Camp Slough Watershed ........... 2-27 2.8 Ecological Processes and Environmental Resources ...................... 2-27 2.8.1 Aquatic Ecosystems and Fisheries ....................................... 2-27 2.8.2 Terrestrial Ecosystems .......................................................... 2-31 2.8.3 Endangered and Listed Species ........................................... 2-32 2.8.4 Ecosystem Challenges .......................................................... 2-35 2.8.4.1 Invasive Species ................................................. 2-35 2.8.4.2 Forest Management ............................................ 2-35 2.9 Water Resources .............................................................................. 2-36 2.9.1 Water Supply ......................................................................... 2-36 2.9.1.1 Surface Water Sources ....................................... 2-36 2.9.1.2 Groundwater Resources ..................................... 2-37 2.9.1.3 Groundwater Supply ........................................... 2-39 2.9.1.4 Regional Water Supplies ..................................... 2-39 2.9.1.5 Recycled Water ................................................... 2-41 2.9.2 Water Demands .................................................................... 2-41 2.9.2.1 Municipal and Agricultural Water Demands ........ 2-42 2.9.2.2 Non-Consumptive Demands – Hydropower Generation .......................................................... 2-44 2.9.2.3 Water Exports from the Region ........................... 2-44 2.10 Water Infrastructure .......................................................................... 2-45 2.10.1 Surface Water Infrastructure ................................................. 2-45 2.10.2 Groundwater Infrastructure ................................................... 2-48 2.10.3 Wastewater and Recycled Water Infrastructure .................... 2-49 2.10.4 Water Treatment and Distribution Infrastructure ................... 2-51 2.11 Water Quality .................................................................................... 2-52 2.11.1 Surface Water Quality ........................................................... 2-55 2.11.2 Groundwater Quality ............................................................. 2-58 2.11.3 Water from Storage ............................................................... 2-62 2.11.4 Current Wastewater and Recycled Water Quality ………….. 2-62 2.12 Storm Water ……………………………………………………………... 2-63 2.12.1 Tuolumne County ……………………………………………….. 2-63 Tuolumne-Stanislaus IRWM Plan, August 2013 ii Table of Contents Table of Contents (cont'd) 2.12.2 Calaveras County ……..………………………………………. 2-65 Section 3: Relation to Local Water and Land Use Planning ...................... 3-1 3.1 Relation to Local Water Planning ....................................................... 3-1 3.1.1 Local Water Supply Planning .................................................. 3-1 3.1.2 Incorporation of Water Planning .............................................. 3-3 3.1.3 Climate Change ....................................................................... 3-4 3.1.4 Making Water Conservation A California Way of Life ………. 3-6 3.1.5 The Sierra Headwaters in this Region ………………………... 3-6 3.1.6 Sustainable Groundwater Management Act …………………. 3-7 3.2 Relation to Local Land Use Planning ................................................. 3-4 3.2.1 Land Use Management Agencies ........................................... 3-4 3.2.2 Agricultural Land Use and the Williamson Act ........................ 3-5 3.2.3 Land Use and Water Resources Planning Collaboration ........ 3-6 3.2.4 Storm Water Planning ………………………………………… 3-14 Section 4: Major Water-Related Needs, Challenges, and Conflicts .......... 4-1 4.1 Introduction ......................................................................................... 4-1 4.2 Efficient Use and Distribution of Water Needs ................................... 4-1 4.2.1 Water Use Efficiency Measures .............................................. 4-1 4.2.2 Water Reuse ........................................................................... 4-2 4.2.3 Renewable Energy .................................................................. 4-2 4.3 Reliable and Affordable Water Supply ................................................ 4-3 4.3.1 Reliable and Affordable Water Supply .................................... 4-3 4.3.2 Water Exports and Senior Water Rights Holders .................... 4-4 4.3.3 Water Storage ......................................................................... 4-5 4.3.4