2020 URBAN WATER MANAGEMENT PLAN Providing Water Security to Western Riverside County for over 60 years

Western is a regional leader for safe, reliable, and affordable water supply. The Western Municipal Water District (Western) was Legend formed in 1954 to bring supplemental water to the Box Springs Mutual Water Company City of Corona City of Norco growing western Riverside county. Today, Western Eagle Valley Mutual Water Company Elsinore Valley Municipal Water District provides water supply, wastewater treatment and Home Gardens County Water District Jurupa Community Services District disposal, and water resource management to nearly Rancho California Water District Riverside Highland Water Company Riverside Public Utilities one million people in a service area covering roughly Rubidoux Community Services District Santa Ana River Water Company 527-square miles in western Riverside County. Temescal Valley Water District Western Retail Western General District Boundary Western serves approximately 25,000 retail and fourteen (14) wholesale customers with water from the Colorado River, State Water Project, recycled water and local groundwater.

39

Glendora Legend 38 83 30 Rancho Western Retail Service Areas Cucamonga Fontana Rialto San BernaWesternrdino General District Boundary

Ontario 0 20,000 40,000 57 Pomona Feet 15 Redlands

Grand Terrace Yucaipa Chino Chino Hills Mira Loma Riverside

Chino Hills State Moreno Valley Park Loma Linda University, County of Riverside, Bureau of Land Management, Esri, 90 HERE, Garmin, USGS, NGA, EPA, USDA, NPS

91 Corona 79 91 0 15,000 30,000 As a member agencyWestern of Municipalthe Metropolitan Water District Water Feet 2020 UWMP and DCP ± Wholesale Service Area and Customers Orange District of Southern California (Metropolitan), Western Perris Wholesale provides supplemental water to the cities of Santa Ana 241

15 Corona, Norco, and Riverside and the water agencies 215 Sun City Irvine serving Box Springs, Eagle Valley, Elsinore Valley, 133 Costa Mesa Temescal Valley, and Temecula. Rancho Santa Margarita Lake Forest Newport Beach Mission Viejo Wildomar 79

San Bernardino 74 Laguna Niguel National Forest 210 Murrieta Los Angeles Ontario Riverside 1 Banning Corona Anaheim 5 Temecula Long BeachSanta Ana

Agua Tibia Murrieta Wilderness 5 San Clemente County of Riverside, Esri, HERE, Garmin, FAO, NOAA, USGS, Bureau of Land Management, County of Riverside, Esri, HERE, Garmin, SafeGraph, FAO, METI/NASA, USGS, EPA, NPS FallbrookBureau of Land Management, EPA, NPS Oceanside 5 Camp Pendleton Escondido Marine Corps Pala Base Reservation Western Retail servesWestern retail Municipal customers Water District directly in 2020 UWMP and DCP Orangecrest, Mission Grove,Vicinity MapEl Sobrante, Eagle Valley, Temescal Canyon, Woodcrest, Lake Mathews, portions of Mead Valley and Perris, and March Air Reserve Base.

WESTERN MUNICIPAL WATER DISTRICT EXECUTIVE SUMMARY 01 2020 URBAN WATER MANAGEMENT PLAN Western’s 2020 Urban Water Management Plan

One document that describes Contents of Western’s 2020 URBAN WATER Western’s water vision. MANAGEMENT PLAN Water agencies in California that The Plan includes sections for serve more than 3,000 customers Western Wholesale and Western PART 1: INTRODUCTION or 3,000 acre-feet (AF) annually Retail, and focuses on the Chapter 1 – Introduction are required by California law following topics: Chapter 2 – Outreach and to prepare an Urban Water Engagement Management Plan (UWMP or Supply and Demand – A detailed Chapter 3 – Service Area Plan) every five years. The Plan analysis of current and future water use and sources of supply Description supports Western’s long-term over a 25-year planning horizon resource planning to ensure PART 2: WESTERN WHOLESALE that adequate water supplies are Water Supply Reliability – Chapter 4 – Wholesale available to meet existing and A detailed assessment of water Water Supply future water needs. The Plan supply reliability Chapter 5 – Wholesale integrates local and regional Drought Risk Assessment – An Water Use land use planning, regional analysis of drought risk assuming Chapter 6 – Wholesale Water water supply, infrastructure, and a five consecutive year drought Service Reliability and Drought Risk Assessment demand management projects, Water Use Efficiency and Chapter 7 – Wholesale Demand as well as statewide issues of Conservation – A summary Management Measures concern like climate change and of water use efficiency and Chapter 8 – Wholesale Water regulatory requirements. conservation programs Shortage Contingency Plan Water Shortage Contingency Plan – A summary of planned PART 3: WESTERN RETAIL responses in the event of a water Chapter 9 – Retail Water Supply shortage Chapter 10 – Retail Water Use Outreach and Engagement – Chapter 11 – Retail Water Service A summary of the outreach, Reliability and Drought Risk communication and engagement Assessment that was conducted in support of Chapter 12 – Retail Demand the Plan Management Measures Chapter 13 – Retail Water Shortage Contingency Plan Western is both a water wholesaler (Western PART 4: SUPPORTING INFORMATION Wholesale) and retailer (Western Retail), References and the 2020 UWMP covers both Appendices roles separately.

WESTERN MUNICIPAL WATER DISTRICT EXECUTIVE SUMMARY 02 2020 URBAN WATER MANAGEMENT PLAN The 2020 UWMP is an Important Part of Water Planning in the Region

The UWMP integrates with many other regional and local planning efforts for planning consistency.

This UWMP is just one of many REGIONAL PLANS WESTERN’S PLANS LOCAL PLANS interrelated local and regional planning efforts Western is either Metropolitan Western Retail leading or coordinating with Integrated Resources Retial Agency UWMPs Facilities Master Plans to secure water supplies for Plan and 2020 UWMP customers within its service area. For more information on the One Water One Western’s 2020 Local Hazard Watershed (OWOW) specific scope and content of UWMP Mitigation Plan Plan each of the plans shown below, refer to Figure 1-2 in the UWMP. Risk and Resilience The 2020 UWMP was prepared 2020 Upper Santa Ana Watershed Integrated Assessment & in parallel with a Drought Emergency Response Regional UWMP Plan Contingency Plan (DCP) that is being developed for the entire Arlington Basin 2019 Water Use Western Wholesale service area. Groundwater Efficiency Master Plan Sustainability Plan

Western 2020 Drought Contingency Plan

WESTERN MUNICIPAL WATER DISTRICT EXECUTIVE SUMMARY 03 2020 URBAN WATER MANAGEMENT PLAN Connecting with Stakeholders and the Public

Western is committed to informing and engaging stakeholders and the general public.

Western is committed to engaging its customers and stakeholders in a proactive and collaborative way to assist in its water planning efforts. The various groups involved with the UWMP and their role are summarized in the graphics below. Western implemented a tiered engagement plan that included local, regional, state and national participation, including the general public and Western’s own Board of Directors.

DROUGHT TASK FORCE MEMBER ORGANIZATIONS

ENVIRONMENTAL AND CONSERVATION GROUPS RETAIL: CUSTOMER STAKEHOLDER Resource Altman Plants Conservation District March Air Reserve Base Inland Empire Waterkeeper Vons/Kroger Riverside-Corona Resource Woodcrest MAC Conservation District Woodcrest MAC/Riverside County Santa Ana Watershed Project Authority WATER AGENCY: REGIONAL ENVIRONMENT AND SOCIAL Eastern Municipal Water District JUSTICE Metropolitan Water District of Southern California Center for Community Action and Western created a webpage to provide Environmental Justice Municipal another opportunity for interested Water District individuals or organizations to learn REGIONAL GOVERNMENT (6%) Box Springs Mutual Water Company more about the UWMP, view the Riverside County Flood Control and Drought Task Force participants and City of Corona Water Conservation District workshop schedules, subscribe to City of Norco Western Riverside Council of project updates, review and comment Governments Elsinore Valley Municipal Water on the Plan and access related District resources. RESEARCH Jurupa Community Services District University of California, Riverside Rancho California Water District Water Resources Institute Riverside Highland Water Company

LOCAL GOVERNMENT Riverside Public Utilities City of Murrieta Rubidoux Community Services District TRIBAL REPRESENTATIVES Temescal Valley Water District Pechanga Tribal Government

Western formed a Drought Task Force that includes diverse perspectives to inform development of the UWMP and the DCP that will be completed in 2022.

WESTERN MUNICIPAL WATER DISTRICT EXECUTIVE SUMMARY 04 2020 URBAN WATER MANAGEMENT PLAN Where Western’s Water Comes From

4 The region relies on a diverse San Bernardino Basin Area water supply portfolio. urupa Community Services District Retail water agencies in Western’s service area Chino Desalter 2 Ruidou CSD City of Riverside SWP rely on a variety of sources to meet demands, 7 City of 8 Norco 9 including imported water, local groundwater and 5 Mills Arlington W 7 recycled water. Many of the supply sources within 1 Desalter TP City of March Air the region are shared by multiple retail water 3 Sterling PS Corona 8 Corona Western Reserve Base agencies, including Western Retail. WTP Riverside Retail Area Corona CRA WTP Lake Matthews 8 SUPPLIES AND INFRASTRUCTURE 10

1 Arlington Desalter and Victoria Recharge Basin Produces drinking water by treating Lake Oroville Imported local non-potable groundwater using lsinore reverse osmosis to remove salt and Water alley MWD other matter. This process also helps Sierra Nevada emescal alley Mountains Water District 8 clean up the groundwater basin and Sacramento improve the quality over time. The Bay Delta Lake CRA new Victoria Recharge Basin captures lsinore stormwater from precipitation 9 and runoff and percolates into the Colorado River California Ski r groundwater basin where it is later Aqueduct Aqueduct Hoover nne used by the Arlington Desalter, Dam WTP increasing local supply reliability. 6 Western Murrieta Retail Area 2 Chino Desalter Western’s Western partners with several other Service Area Rancho California water agencies to treat local non- Water District Western potable groundwater using reverse Rainbow osmosis to create a new high quality Retail Area drinking water supply. 3 Sterling Pump Station and 6 Groundwater La Sierra Pipeline Western has rights to produce The recently completed Sterling water from this basin for service to pump Station and La Sierra Pipeline Western’s Murrieta Retail system. 9 Mills and Skinner Water connect the Chino and Arlington 7 Recycled Water a Local Drought Treatment Plants (WTP) Desalters to and allow Western Metropolitan treats imported water to deliver both water sources to Proof Supply Western provides recycled water and at their Mills and Skinner WTPs many different locations, increasing and provides potable imported regional reliability. non-potable groundwater to meet non-potable irrigation water needs, water to Western to distribute to Western Retail and other wholesale 4 San Bernardino Basin (SBBA) preserving the potable supplies for Western owns rights to pump local domestic use. customers. potable groundwater from the SBBA 8 10 Mills Gravity Line and has a long term lease with Meeks Imported Water Western Wholesale obtains potable Deliver treated imported water from & Daley Water Company to use the Mills WTP to Western Retail additional water from the SBBA. and nonpotable imported water supply from the SWP and CRA and several Western Wholesale customers. 5 City of Riverside through Metropolitan at various Western has an agreement with locations and delivers it to Western Riverside to purchase their surplus Retail and other wholesale customers Wholesale Retail local groundwater. Riverside also in their service area. Some Western pumps and delivers Western’s water Wholesale customers receive Wholesale & Retail raw imported water directly from from the SBBA to Western Retail at CRA - Colorado River Aqueduct interconnections using their existing Metropolitan pipelines and use the facilities. water for groundwater recharge or SWP - State Water Project treat it at their own treatment plants for potable use.

WESTERN MUNICIPAL WATER DISTRICT EXECUTIVE SUMMARY 05 2020 URBAN WATER MANAGEMENT PLAN Total Water Use within Western’s Service Area

TOTAL WATER USE IN WESTERN’S SERVICE AREA Western’s retail agencies rely FROM 2016 THROUGH 2020. on a mix of supplies, and not all supply comes from Western. 300,000 273,043 280,329 281,124 231,922 245,048 250,000 Total water use within Western’s service area has 200,000 ranged from approximately 230,000 AF to more 150,000 than 280,000 AF in the last five years, including 100,000 Western Retail. In 2020, approximately 36% of the total water used withing Western’s service area 50,000 was provided by Western Wholesale. In addition to - wholesale water purchased from Western, most of 2016 2017 2018 2019 2020 the water purveyors within Western’s service area Imported Treated Imported Untreated Groundwater also deliver local surface and groundwater and/or Groundwater - Desalter Surface Water Recycled Water recycled water within their respective service areas Total Water Use and some rely solely on local water supplies.

Western Wholesale delivers potable and non-potable supplies to its wholesale customers. Western Wholesale’s total demand is expected to increase from 74,927 AF in 2020 to over 121,000 AF in 2045.

PROJECTED RETAIL DEMAND, AFY. PROJECTED WHOLESALE DEMAND, AFY, INCLUDING WESTERN RETAIL DEMANDS.

140,000 140,000 121,443 112,664 120,000 120,000 106,261 96,816 100,908 100,000 100,000 80,000 80,000

60,000 42,155 46,940 60,000 33,879 37,792 40,000 30,167 40,000 20,000 20,000 - - 2025 2030 2035 2040 2045 2025 2030 2035 2040 2045

Potable Demands Non-Potable Demands Potable Demand Non-Potable Demand Total Retail Demands Total Whole sale D ema nd

WESTERN MUNICIPAL WATER DISTRICT EXECUTIVE SUMMARY 06 2020 URBAN WATER MANAGEMENT PLAN Using Water Wisely

Western is an active and visible advocate and resource for wise water use in the region.

Western has been a leader in 20% BY 2020 water use efficiency for many By 2009, Western Retail had met their target to reduce per capita water consumption years and actively collaborates by 20% by 2020 and went on to achieve a reduction of more than 50% by 2020. with local and regional agencies Activities that have affected retail water usage in Western Municipal Water District. and the communities it serves to implement innovative programs 430 Baseline Water Use from 1995-2004, gallons per capita per daydrop and drive reductions in water usage. Western staff also serves in 352 2020 Water Use Target a leadership role for the California STAGE STAGE STAGE STAGE STAGE DROH 383 2 1 4B 3B 2 Water Efficiency Partnership SAS

(CalWEP) whose mission is to 353 Statewide Drought: Wet Wet Period State of Emergency Period Declaration maximize urban water efficiency CLIMA and conservation throughout 326 Recession COVID-19 285 289 California by supporting CONOM 277 and integrating innovative 269 267 Planning and Public Outreach Water Budgets Implemented for Water Budgets technologies and practices; WMWD 224 encouraging effective public 209 205 Water Use Efficiency Plan 199 201 WAR S Programs Water Use policies; advancing research, 186 Efficiency ICINC Plan Update training, and public education; 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 and building collaborative NEW ORDINANCES approaches and partnerships. Water use efficiency is a core business component in Western’s customer partnership with both wholesale and retail customers.

WESTERN MUNICIPAL WATER DISTRICT EXECUTIVE SUMMARY 07 2020 URBAN WATER MANAGEMENT PLAN Western’s Supplies are Reliable, Even in Drought

PROJECTED WESTERN WHOLESALE SUPPLIES IN A Western’s diverse supplies and SINGLE DRY YEAR, AFY continued investments provide 140,000 121,443 112,664 reliable water for the region. 120,000 106,261 96,816 100,908 100,000 Western evaluates the reliability of its supplies 80,000 considering short and long-term variations in 60,000 weather and climate patterns, including the impacts 40,000 of climate change. Additionally, Western’s supply 20,000 sources may be impacted by water quality and legal restrictions, environmental and/or ecological - 2025 2030 2035 2040 2045 constraints, as well as potential for interruption of supply driven by catastrophic events. Local Potable Supply Imported Potable Supply Imported Non-Potable Supply Total Wholesale Supply To address these risks, Western and Metropolitan invest in a variety of projects and programs to PROJECTED WESTERN RETAIL SUPPLIES IN A SINGLE enhance water supply reliability. These include DRY YEAR, AFY investing in water conservation and development 60,000 of local supplies, as well as storage, transfer and 52,900 47,540 50,000 exchange programs, and improvements in regional 42,650 infrastructure. Metropolitan is also pursuing solutions 38,265 40,000 34,104 in enhance reliability of SWP supplies through long- term investments in the Sacramento-San Joaquin 30,000 Delta (Bay-Delta). The net effect is a very robust 20,000 and reliable supply, even under extended drought 10,000 conditions. 0 2025 2030 2035 2040 2045 Western evaluated supply reliability during a single Local Supply Imported Potable Supply Imported Non-Potable Supply Surplus Supply dry year, multiple dry years, and a multiple year Total Supply drought that could potentially occur within the next five years (2021-2025). In all cases, Western’s supplies were sufficient to meet demand without any supply shortages.

WESTERN MUNICIPAL WATER DISTRICT EXECUTIVE SUMMARY 08 2020 URBAN WATER MANAGEMENT PLAN What Happens if Supplies are Interrupted?

Western’s Water Shortage Contingency Plan (WSCP) describes how Western is preparing for and may respond to potential water shortage.

A water shortage occurs through proactive, rather than when water supply available is reactive, mitigation of water insufficient to meet the normally shortages. The Western WSCP expected customer water use at provides a process for an annual a given point in time. A shortage water supply and demand may occur due to several assessment and structured steps reasons, such as water supply designed to respond to actual quality changes, climate change, conditions. Although Western drought, regional power outage, does not foresee implementing and catastrophic events (e.g., water shortage levels for earthquake). Additionally, the Western Wholesale or Western State may declare a statewide Retail unless determined by drought emergency and Metropolitan, this level of detailed mandate that water suppliers planning and preparation provide reduce demands, as occurred accountability and predictability in 2014. The WSCP serves as and help Western maintain the operating manual that reliable supplies and reduce the Western will use to prevent impacts of any supply shortages catastrophic service disruptions and/or interruptions.

WESTERN MUNICIPAL WATER DISTRICT EXECUTIVE SUMMARY 09 2020 URBAN WATER MANAGEMENT PLAN Looking to the Future – Delivering Long-term Water Security

Western is poised for continued leadership to support the region’s long-term water security.

Western has ongoing programs to continue its mission of providing safe, reliable, environmentally sensitive, and financially responsible water resources for its customers.

Securing local water resources

Collaborating Making water with Metropolitan conservation in securing a way of life imported supplies

Additionally, Western is currently partnering with the Drought Task Force to prepare a Drought Contingency Plan (DCP) that takes a deeper dive into drought planning and preparedness across Western’s entire service area, including an in-depth evaluation of the potential range of impacts of climate change on Western’s long-term supplies.

STAY INFORMED AND INVOLVED

Tap into education, advocacy and awareness by staying involved with Western.

@WesternMWD @WesternMWD To stay informed and involved in Western’s ongoing programs and efforts, check out our website at www.wmwd.com, or @WesternMWD ww.WMWD.com follow us on Facebook, Twitter and Instagram.

WESTERN MUNICIPAL WATER DISTRICT EXECUTIVE SUMMARY 10