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2020 Urban Water Management Plan 2020 URBAN WATER MANAGEMENT PLAN JUNE 2021 This page intentionally blank 2 2020 URBAN WATER MANAGEMENT PLAN City of El Centro Prepared for: City of El Centro 1275 W. Main Street El Centro, CA 92243 Prepared by: 5 Hutton Centre Drive, Suite 300 Santa Ana, CA 92707 Date: June 2021 This page intentionally blank ii City of El Centro 2020 Urban Water Management Plan Table of Contents TABLE OF CONTENTS Acronyms and Abbreviations ........................................................................................................................ xi 1 INTRODUCTION.................................................................................................................................. 1-1 1.1 Urban Water Management Plan Requirements ........................................................................... 1-1 New Requirements Since 2015 ........................................................................................ 1-1 Senate Bill 7 of the Seventh Extraordinary Session of 2009, Water Conservation in the Delta Legislative Package ...................................................................................... 1-2 Assembly Bill 1668 and Senate Bill 606 ........................................................................... 1-2 1.2 Lay Description ............................................................................................................................ 1-3 Chapter 1: Introduction ..................................................................................................... 1-3 Chapter 2: Plan Preparation ............................................................................................. 1-3 Chapter 3: System Description ......................................................................................... 1-4 Chapter 4: System Water Use Characterization .............................................................. 1-4 Chapter 5: SBx7-7 Baselines and Targets ....................................................................... 1-4 Chapter 6: Water Sources and Supply Reliability ............................................................ 1-4 Chapter 7: Water Service Reliability and Drought Risk Assessment ............................... 1-5 Chapter 8: Water Shortage Contingency Plan ................................................................. 1-5 Chapter 9: Demand Management Measures ................................................................... 1-5 Chapter 10 Plan Adoption, Submittal, and Implementation ............................................. 1-6 2 PLAN PREPARATION ......................................................................................................................... 2-1 2.1 Basis for Preparing a Plan ........................................................................................................... 2-1 2.2 Individual or Regional Planning and Compliance ........................................................................ 2-1 2.3 Fiscal or Calendar Year and Units of Measure ............................................................................ 2-2 2.4 Coordination and Outreach .......................................................................................................... 2-3 3 SYSTEM DESCRIPTION ..................................................................................................................... 3-1 3.1 General Description ..................................................................................................................... 3-1 2012 Imperial Region Integrated Regional Water Management Plan and IID’s 2021 Water Supply Template ............................................................................................ 3-1 Colorado River Water Supply via Imperial Irrigation District ............................................ 3-3 City of El Centro ............................................................................................................... 3-4 3.1.3.1 City Water System Description ............................................................................... 3-6 i City of El Centro Table of Contents 2020 Urban Water Management Plan 3.2 Service Area Boundaries ............................................................................................................. 3-7 3.3 Service Area Climate ................................................................................................................... 3-8 3.4 Service Area Population and Demographics ............................................................................... 3-9 Service Area Population ................................................................................................... 3-9 Water-Use-Related Land Use Planning .........................................................................3-10 4 SYSTEM WATER USE CHARACTERIZATION .................................................................................. 4-1 4.1 Recycled Versus Potable and Raw Water Demand .................................................................... 4-1 4.2 Water Use by Sector .................................................................................................................... 4-2 Water Use Sectors Listed in Water Code ........................................................................ 4-2 Non-Revenue Water ......................................................................................................... 4-3 Past and Current Water Use ............................................................................................ 4-4 4.3 Projected Water Use .................................................................................................................... 4-5 Demand Projection Methodology ..................................................................................... 4-5 25-Year Projections .......................................................................................................... 4-8 4.4 Worksheets and Reporting Tables .............................................................................................. 4-8 Submittal Table 4-1: Total Gross Water Demand by Sector – 2020 ................................ 4-8 Submittal Table 4-2: Gross Water Use by Sector - Projected .......................................... 4-9 Submittal Table 4-3: Total Gross Water Use (Potable and Non-Potable) ........................ 4-9 Submittal Table 4-4: Preceding Five-Year Water Loss Audit Reporting ........................4-10 4.5 Water Use for Lower Income Households .................................................................................4-11 4.6 Climate Change Considerations ................................................................................................4-13 5 SBx7-7 BASELINES AND TARGETS ................................................................................................. 5-1 5.1 Baseline Water Use ..................................................................................................................... 5-1 Ten- to Fifteen-Year Baseline Period (Baseline GPCD) .................................................. 5-1 Five-Year Baseline Period (Target Confirmation) ............................................................ 5-2 Service Area Population ................................................................................................... 5-2 5.2 SBx7-7 Water Use Targets .......................................................................................................... 5-2 SBx7-7 Target Methods ................................................................................................... 5-2 2020 Target ...................................................................................................................... 5-3 5.3 Regional Alliance ......................................................................................................................... 5-4 ii City of El Centro 2020 Urban Water Management Plan Table of Contents 6 WATER SOURCES AND SUPPLY RELIABILITY ............................................................................... 6-1 6.1 Purchased Imported Water .......................................................................................................... 6-1 Colorado River Rights ...................................................................................................... 6-1 6.1.1.1 Colorado River Compact (1921) ............................................................................. 6-2 6.1.1.2 Boulder Canyon Project Act (1928) ........................................................................ 6-2 6.1.1.3 California Seven-Party Agreement (1931) ............................................................. 6-2 IID State Applications and Permits ................................................................................... 6-4 Subordination by Coachella Valley Water District ............................................................ 6-4 6.2 IID Present Perfected Rights, and Arizona v. California US Supreme Court Decision (1964, 1979) ................................................................................................................................. 6-5 Colorado River Basin Project Act (1968).......................................................................... 6-6 Quantification Settlement Agreement & Related Agreements (2003) .............................. 6-6 6.2.2.1 Colorado River Water Delivery Agreement (CRWDA) ........................................... 6-7 6.2.2.2 Inadvertent Overrun
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