Hesperia City Council
June 2, 2026

Sub-Chapter 6.2 – Water Service and
System Description
The Agency manages water supplies from the urban, rural, industrial, recreational, and agricultural users throughout its expansive service area, depicted in Figure 2-1, which covers large portions of eastern San Bernardino County and the California side of the Mojave Desert.

The Mojave River is central to MWA history and settlement in the region. The river is more of an ephemeral stream which derives its flow from drainage of 217 square miles of the northern slope of the San Bernardino Mountains. Early farmers aggressively planted the Victor Valley with fruit trees and crops, which by the 1950s created serious water overdraft. This overdraft led to a halt in development in the area. Legislation for the SWP passed in 1959 to begin work on the California Aqueduct, along with the Davis-Grunsky Act, which afforded regions the opportunity to form local water agencies. Soon after, in 1960, the Mojave Water Agency was formed.

MWA’s service area is divided into seven divisions, each one represented by a publicly elected board member who serves a four-year term. The MWA Board uses a committee format to inform decisions and receive recommendations for voting matters with each committee member serving a one-year term (or until a successor is appointed). These committees generally meet once a month and include: Legislative and Community Partners Committee; Planning, Resources, Engineering and Operations Committee; Personnel, Finance, Security and Technology Committee; Morongo Basin Pipeline Commission; Technical Advisory Committee; and Watermaster.

MWA’s Sphere of Influence (SOI) is generally contiguous with its service area; however, there are two areas within the SOI that are currently not in its service area. Golden State Water Company serves the Wrightwood community’s 2,700 customers on the southern boundary of the MWA SOI. The other area is near Grass Valley Creek, which is a tributary to the Mojave River. These two areas are at the base of the San Bernardino Mountains and are part of the headwaters that connect the drainage to the groundwater basins that are part of the MBA Adjudication. MWA, serving as the court appointed MBA Watermaster according to the MBA Judgment, coordinates with these entities within the SOI to ensure established water supplies into the subbasins are maintained. An overview of the MBA Judgment is described in Chapter 3 – Regional Water Supply Characterization.

As also described more thoroughly in Chapter 3, water supply for MWA’s service area is sourced almost entirely from pumped groundwater from the various basins, subbasins, and aquifers in the area. MWA’s role is to help manage the groundwater basins by importing and managing delivery of imported supplies. To help with this, two primary water delivery projects were developed to deliver much-needed supply to additional locations in MWA’s service area from the SWP. The Morongo Basin Pipeline (MBP), completed in 1995, provides imported water to the upper portions of Mojave River Basin and to the Morongo subarea. The Mojave River Pipeline, completed in 2006, provides critical recharge to lower portions of Mojave River Basin (e.g. Centro and Baja subareas) and, more recently, will provide supplies to the Regional Aquifer west of Victorville.

6.2.1 Service Area Climate
A thorough description of the Mojave Region’s climate and considerations of climate change are included in Chapter 2 – The Mojave Region. Since MWA’s service area is concurrent with the Region’s boundary, details in Chapter 2 sufficiently address this UWMPA requirement and no additional details are provided in this sub-chapter.

Sub-Chapter 6.3 – Population, Land
Use, Economy, and Demographics
Service area population and land use projections are critical to developing a useful planning framework as population dynamics and growth are a primary influence on water use in the Mojave Region. These projections directly influence planning measures for system supply, delivery, infrastructure, and demand management. Because MWA’s service area is concurrent with the Mojave Region as defined for this 2025 RUWMP, the regional population, land use, economic, and demographic conditions applicable to MWA are described in Chapter 2 – The Mojave Region.

Accordingly, this sub-chapter does not repeat the full regional population and land use discussion provided in Chapter 2. Instead, it identifies the subset of the regional population that is directly relevant to MWA’s wholesale demand forecast: the small water system and rural domestic user population located outside the service area boundaries of the participating urban water retail suppliers. This population is summarized at the regional level in Table 2-8 and is further organized by RUWMP Subregion in Table 6-2 to support the water demand forecast presented in Sub-Chapter 6.6 – Water Use Characterization.

6.3.1 Small Water System and Rural Domestic User
Population
The MWA population presented in Table 2-8 represents the portion of the Mojave Region associated with small water systems and rural domestic users outside the service area boundaries of the participating urban water retail suppliers. While Table 2-8 summarizes this population at the regional level, the water demand forecast presented in Sub-Chapter 6.6 requires this population to be organized by RUWMP Subregion.

To support this subregional breakout, residential lands outside the service area boundaries of the participating urban water retail suppliers were identified using the SCAG HELPR 2.0 land use shapefile.
35 Lands designated as Mixed Use Residential, Commercial and Mixed Use Residential, Mobile Home and Trailer Parks, Multi-Family Residential, Rural Residential, and 35 SCAG HELPR 2.0 shapefile accessed at: https://rdp.scag.ca.gov/helpr/?page=Main-Page

Single-Family Residential were classified as residential for purposes of this analysis. These residential lands were then assigned to the appropriate RUWMP Subregion.

The number of residential parcels within each Subregion was used to determine the proportional share of the total small water system and rural domestic user population presented in Table 2-8. This method allowed the regional population total to be distributed among Subregions in a manner that reflects the relative location of residential land uses outside the participating retailer service areas. The resulting population projections are presented in Table 6-2 and provide basis for the small water system and rural domestic demand forecast presented in Sub-Chapter 6.6.

T
ABLE 6-2: PROJECTED SMALL WATER SYSTEM AND RURAL DOMESTIC USER POPULATION 2030-2050 Subregion 2030 2035 2040 2045 2050
Subregion 1 57,994 57,080 54,852 52,328 46,747
Subregion 2 14,075 13,853 13,313 12,700 11,345
Subregion 3 12,415 12,220 11,743 11,202 10,007

Sub-Chapter 6.4 – Imported Water
Supply and Reliability
Characterization
This sub-chapter describes MWA’s water supply sources. The description includes the historical sources available to MWA as well as projected water supply sources through 2050.36 MWA delivers imported surface water to recharge facilities and groundwater systems throughout its service area, where the water contributes to local aquifer replenishment and can subsequently be extracted by retail agencies and other water users.

MWA categorizes its supply sources in essentially two groupings. The first grouping includes supply sources that are generally available on an annual basis. These sources include MWA’s SWP supplies that are made available each year. Other sources may occasionally fall into this category but are not incorporated into this RUWMP. The second set of supply sources are those that MWA could make available in any given year but are generally not renewable in MWA’s supply portfolio once they are used. In other words, although they can be replaced, like a water savings account, they are not guaranteed to be replaced on an annual basis. MWA’s long-term water supply management actions focus on optimal utilization of its annually available supply sources and protection of its pre-stored supply sources to guard against extended drought conditions and catastrophic outage impacting water users in the Region.

This sub-chapter describes MWA’s water supply portfolio and develops a supply matrix that integrates the supply sources to reflect MWA’s operational objectives.

6.4.1 State Water Project
The SWP provides a primary water supply for MWA. The water supply is derived from a series of water rights and water contracts as well as pumping and conveyance structures that connect the SWP supplies to MWA’s delivery system as described in Chapter 2 – The Mojave Region. MWA became a State Water Project contractor in June 1963, entering into a water service contract with the California Department of Water Resources (DWR). 36 The UWMP Act mandates a 20-year planning horizon and the 2025 UWMP Guidebook recommends a 25 year planning horizon.

6.4.1.1 SWP Table A Contract Amount
MWA’s SWP Contract amount (Table A) has gradually increased since the Agency started taking deliveries in 1972. Initially the maximum Table A amount was 8,400 acre-feet per year (AFY) escalating to 50,800 AFY by 1990. MWA participated in two notable Table A permanent transfers, one in 1997 with Kern County Water Agency that augmented MWA’s Table A by 25,000 AFY, and one in 2009 with Dudley Ridge Water District for 14,000 AFY that stepped up the Table A amount in three increments (7,000 AF in 2010, 3,000 AF in 2015, and the final 4,000 AF in 2020). MWA’s current maximum SWP Contract Table A is 89,800 AFY.

MWA’s SWP Contract has numerous components that allow MWA to administer and control the annually available SWP water supplies. MWA’s SWP Contract has six important provisions that characterize the available supplies and the water delivery activities. The key aspects are:
(1) Annual Table A Amount, (2) Annual Table A Allocation, (3) Article 56 Carryover, (4) Article 21 Surplus Supplies, (5) Article 12(f) on SWP conveyance priorities, and (6) water transfer and exchanges supported by Amendment No. 17, the “Water Management Tools”.

As mentioned previously, MWA's Annual Table A Amount is 89,800 AFY, representing the maximum Table A amount available to the Agency under its SWP Contract. Although MWA’s SWP Contract provides for the Annual Table A Amount, that total volume of water supply is subject to reduction each year based on actual water supply availability in the SWP system as determined by DWR. The last 100% allocation year occurred in 2023. However, actual deliveries vary widely with significantly reduced percentages of maximum contract amount being available during drought years. The long-term average annual Table A Allocation provided by DWR’s 2025 Delivery Capability Report (DCR) is 54%. 37 Since 2005 the DCR’s
estimated average of total annual Table A water deliveries has decreased from 2,828 thousand acre-feet (TAF) to 2,234 TAF. This is based on several factors of note, including hydrology,
38 infrastructure issues through the system, Delta regulations which constrained exports, and updates to the CalSim3 model. As such, the estimated long-term average annual Table A deliveries were adjusted down from 57% of maximum in 2021, to the Final DCR 2025 long-term average estimate of 54% under existing climate conditions. 37 The DWR 2025 Delivery Capability Report uses a hydrological modeling simulation to determine estimated deliveries under existing conditions using a historical time period from 1922-2021. Future delivery capability conditions are also modeled using these simulations along with CalSim3 and multiple climate change scenarios and future SWP system performance “levels of concern”. Projections of future delivery capability are not part of this analysis.
38 The 2025 DCR adjusted its hydrological baseline that incorporates statistically significant changes rim inflow from the rim watersheds into California’s Central Valley in which standard deviations of precipitation and runoff during the early periods of the past 100 years are significantly different from the recent 30 years due to climate change.

As a point of reference, from 2010-2025, the average Table A Allocation for MWA was 39,218 AF (46% of max) in which allocations during that 15-year span ranged from 5% - 100%, as presented in Table 6-3. Average Table A Allocations over this period closely align with the 2025 DCR model projections for future conditions that incorporate climate change.39 It is important to note that extreme hydrologic variability may become more commonplace in future climate scenarios, and MWA could experience drastic variations in Table A Allocation and deliveries in the future.

T
ABLE 6-3: MWA’S HISTORIC SWP TABLE A ALLOCATIONS AND DELIVERIES Year MWA Contract Amount (AF) Table A Allocation Annual Allocation Amount (AF) 2010 82,800 50% 41,400
2011 82,800 80% 66,240
2012 82,800 65% 53,820
2013 82,800 35% 28,980
2014 82,800 5% 4,140
2015 82,800 20% 16,560
2016 85,800 60% 51,480
2017 85,800 85% 72,930
2018 85,800 35% 30,030
2019 85,800 75% 64,350
2020 89,800 20% 17,960
2021 89,800 5% 4,490
2022 89,800 5% 4,490
2023 89,800 100% 89,800
2024 89,800 40% 35,920
2025 89,800 50% 44,900
Average Allocation and Deliveries: 46% 39,218
39 Climate change effects modeled into the DCR delivery capability estimates include changes to monthly patterns of flows, more extreme hydrologic and drought events, and lower reservoir storage levels. Long-term average Table A delivery projections are estimated between 43-48% of maximum. (2025 DCR at Section 6, Table 6-2.)

MWA's annual Table A allocation has specific utility to provide replacement water for the adjudicated basins and support sustainable groundwater management. The Morongo Basin Pipeline and Mojave River Pipeline, along with the Mojave River itself, deliver this imported water directly to dedicated recharge facilities throughout the various adjudicated subareas.

MWA utilizes SWP water primarily for groundwater recharge at these facilities, while maintaining over 250,000 acre-feet of stored water supplies both within local groundwater basins and as carryover storage in the SWP system to provide reliability during drought conditions and ensure long-term water security for the numerous retail water suppliers and end users within its service area.

6.4.1.2 Article 21
Article 21 of MWA’s SWP contract outlines the rules for “interruptible water service.” Interruptible water service means allocation of water that is essentially surplus in the SWP system and is in addition to the Table A Allocation in any given year. In other words, DWR may determine at a later date that there is additional water that could be delivered to requesting contractors that is in excess to that system-wide Table A Allocation. Article 21 was recently amended (Contract Amendment 17), and outlines the provisions for allocation, notice, and process for obtaining, rates, and transfers of Article 21 interruptible water. Notably, Amendment 17 allows for transfers of Article 21 water from certain SWP contractors to others if the contractor can demonstrate a special need for the transfer.

As a SWP Contractor, the Agency has access to Article 21 water when “excess” water is made available. Article 21 water is identified as non–Table A water that becomes available on an intermittent, interruptible basis. Allocations of Article 21 water are made based on the available supply in proportion to each contractor’s annual entitlement as set forth in its Table A for that year.

When available, Article 21 water delivery is typically made in the wettest months of the year, December through May. As such, Article 21 water is sometimes called “wet weather water”. It is offered to contractors when there is ample water in the system, and the State publishes a notice to contractors when it is made available. Article 21 water is not available for carryover storage in SWP facilities; however, a change in point of delivery is possible with a separate agreement with DWR in order to store Article 21 water outside of the service area. Notifications of Article 21 water availability come based on forecasting and existing hydrology, and the Article provides for the timely processing of requests by contractors for delivery. Demands are typically submitted for Article 21 water on a weekly basis.

The ability to take advantage of Article 21 water for MWA requires access to conveyance capacity in the aqueduct and available storage outside of San Luis Reservoir. Importantly, that priority for conveyance within the SWP goes to Table A water, and Article 21 water delivery may be interrupted if it is impacting a contractor’s Table A water delivery through a shared reach of the aqueduct. The Agency’s location on the East Branch of the aqueduct factors into the inherent conveyance priority limitations associated with Article 21 water.

The 2025 SWP Delivery Capability Report indicates that Article 21 availability will be more frequent, especially in very wet years. Between 2000–2020, Article 21 water was available in all but two years; however, during multi-dry year stretches such as 2008-2010 and 2014–2016 the amount of Article 21 water available was orders of magnitude smaller than in normal to wet years. In summary, Article 21 water requires opportunistic operational flexibility for storage and conveyance capacity in the aqueduct to maximize its intermittent availability. Because of this uncertainty, this RUWMP does not include Article 21 as a quantifiable part of MWA’s water supply. Rather, MWA will continue to be opportunistic and access this supply as may best serve longer-term imported water policy objectives and groundwater basin needs.

6.4.1.3 Article 56 Carryover
Article 56 of MWA’s SWP Contract outlines the rules for storing unused Table A Allocation in any year for use in a subsequent year. The Article 56 Carryover water is stored in San Luis Reservoir. There are limitations to the total carryover amounts, subject to a percentage of the Annual Table A Amount, dependent on the final allocation percentage for that year. For example, if the final Table A Allocation was 50% (44,900 AF), MWA could store (carryover) 25% of its Table A Amount (22,450 AF). If storage requests exceed capacity in San Luis Reservoir, the available capacity will be allocated among contractors in proportion to their Table A entitlement. Reallocation can also result in “displacement” of stored water, sometimes known as “spill” that results in stored amounts being released.

Storing water in San Luis Reservoir for multiple years is allowed but comes with risk because of the potential of losing the stored water due to capacity restraints. Nevertheless, storage of SWP water in San Luis Reservoir under Article 56 is a critical component of MWA’s water asset management portfolio because it is a south of Delta storage option that allows carryover in multiple years. As an example of how this supply is managed, MWA had about 20,400 acre- feet of Article 56 supply available coming into the 2025 delivery year.

Due to the circumstances and water management choices made by MWA in 2025, a small amount of the available Table A supply was added to the carryover, resulting in the end-of- year 2025 Article 56 total being slightly over 21,000 acre-feet. Due to hydrologic and operational conditions in early 2026, a portion of this carryover supply was at risk of spilling.

MWA anticipates that carryover storage by the end of 2026 will be slightly more than 12,500 acre-feet. The difference is expected to be used as part of MWA’s broader imported water management strategy, including meeting regional needs in 2026, potentially increasing storage in local subareas, and supporting transfers to other SWP contractors.

Although MWA may use its carryover supplies under normal year conditions, it generally preserves these supplies to manage shortage conditions derived from extended drought or catastrophic water outages.

6.4.1.4 Summary of Historic SWP Deliveries
Collectively, MWA manages its SWP water supplies based on a variety of conditions, with each year reflecting a slight variance in both allocations, deliveries into the Region, and storage or sales to other parties. Table 6-4 shows this variance between 2010 and 2025 while Figure 6-1 provides a useful representation of how MWA evaluates and tracks its available SWP supplies year-over-year.

T
ABLE 6-4: SWP ALLOCATION COMPARED TO ACTUAL DELIVERIES INTO MWA SERVICE AREA Year Allocation Table A Amount (AF) Actual Deliveries (AF) 2010 50% 44,900 35,566
2011 80% 71,840 48,775
2012 65% 58,370 26,175
2013 35% 31,430 7,398
2014 5% 4,490 3,595
2015 20% 17,960 8,909
2016 60% 53,880 23,574
2017 85% 76,330 34,750
2018 35% 31,430 5,869
2019 75% 67,350 21,824
2020 20% 17,960 3,379
2021 5% 4,490 2,306
2022 5% 4,490 4,536
2023 100% 89,800 99,471*
2024 40% 35,920 2,618
2025 50% 44,900 19,220

FIGURE 6-1: EXAMPLE REPRESENTATION OF MWA’S ANNUAL MANAGEMENT OF SWP SUPPLIES

6.4.2 SWP Restrictions
Neither DWR nor the SWP guarantees delivery of 100% of water allocations every year. Under the historic lowest 5% of allocations, SWP deliveries to MWA were 4,490 AF for the year. This, in conjunction with the expected decrease in reliability of the SWP over time, places a significant constraint on the reliability of SWP supplies as a source of imported water for recharge of the Region’s managed groundwater supplies. In addition to SWP system conveyance capacity limitations, MWA’s SWP supplies are also subject to notable policy and regulatory constraints.

6.4.2.1 The Delta Reform Act
The Delta Reform Act (DRA) of 2009 established the Delta Plan and the Delta Stewardship Council.
40 Ultimately, the DRA requires water purveyors to reduce reliance on water supplies derived from the Sacramento-San Joaquin Delta and improve reliance on locally developed water sources (see this RUWMP’s representation of compliance in Chapter 3 – Regional Water Supply Characterization). The Delta Plan is the governing document that guides the Delta’s future and spawned the DRA regional self-reliance policies. The Delta Plan has two “co-equal goals:” (1) providing a more reliable water supply for California; and (2) protecting, restoring, and enhancing the Delta ecosystem.
40 California Water Code Section 85225

Specifically, urban water purveyors should demonstrate consistency with Delta Plan Policy WR P1 – Reduce Reliance on the Delta Through Improved Regional Water Self-Reliance (WR P1).41 WR P1 subsection (a) states that:

Water shall not be exported from, transferred through, or used in the Delta if all of the following apply:
1) One or more water suppliers that would receive water as a result of the export, transfer, or use have failed to adequately contribute to reduced reliance on the Delta and improved regional self-reliance consistent with all of the requirements listed in paragraph (1) of subsection (c);
2) That failure has significantly caused the need for the export, transfer, or use; and 3) The export, transfer, or use would have a significant adverse environmental impact in the Delta.

The DRA is relevant to MWA’s water asset portfolio and the water asset portfolios of its retailers because the DRA’s rules require reduced reliance on water supplies derived from the Delta in favor of locally developed water supplies. The methodology needed to comply with DRA’s regulatory requirement as noted in the policy is a reduction in “the percentage of water used from the Delta watershed.”

6.4.2.2 Healthy Rivers and Landscapes
The Bay Delta Plan's Healthy Rivers and Landscapes program, implemented through Voluntary Agreements (VAs), establishes specific "forgone export" requirements that would directly restrict SWP deliveries to south-of-delta contractors. Under these agreements, DWR and the Bureau of Reclamation must reduce exports from key Delta pumping facilities (Jones Pumping Plant and Clifton Court Forebay) based on water year types. The required export reductions range from zero in critical and wet years to 125,000 acre-feet in dry and below normal years, and up to 175,000 acre-feet in above normal years. These forgone exports are designed to ensure that additional upstream flows provided under the VAs actually reach the Delta as outflow rather than being captured by the export facilities.

The restriction mechanism works by establishing "reference conditions" representing pre-VA baseline operations, then requiring that SWP and Central Valley Project operations avoid exporting both these reference flows and the new additive VA flows. This creates a complex accounting system where south-of-delta water contractors would experience reduced deliveries not only from the direct export limitations, but also from the operational constraints needed to ensure VA tributary flows bypass the pumps and contribute to Delta outflow. The 41 Cal. Code Regs., tit. 23 Section 5003.

program includes detailed daily and monthly tracking requirements to verify that the projects are indeed forgoing exports rather than simply capturing the additional upstream flows, effectively prioritizing ecosystem benefits over south-of-delta water supply reliability.

6.4.3 Delta Conveyance Project
The Delta Conveyance Project (DCP) is a proposed project by DWR to mitigate lost supply to the SWP associated with transporting water through the Sacramento-San Joaquin Delta (Delta). SWP contractors situated south of the Delta are exposed to multiple risk scenarios for long-term SWP supplies, including previously discussed regulatory compliance statutes.

Additional mitigation against other water supply risks driven by rising sea levels, earthquakes, progressive risk of levee failures, and extreme drought and flood are also identified as DCP benefits. Continuation of existing operation of the Delta is expected to increasingly expose water users that depend on water exported from the Delta to risks of interrupted water supply and decreasing water supply reliability over time. In short, the DCP is a significant risk mitigation component to help overcome uncertainties associated with conveying SWP water through the Delta.

MWA is an investor and participant in the DCP. The investment costs associated with MWA’s role are to fund the work plan and reserve capacity space in the project. The DCP does not increase water rights associated with the SWP but rather would restore losses caused by current physical and regulatory issues and mitigate against future changed conditions affecting SWP exports by adding a new point of diversion in the northern Delta. The Final Environmental Impact Report for the DCP was certified by DWR in December 2023 and a Change in Point of Diversion Petition was filed with State Water Resources Control Board (SWRCB) February 22, 2024. MWA’s participation in the DCP is safeguard for long-term supply reliability for the Region and its critical imported water supply.

6.4.4 Evaluating and Managing Supply Reliability Risks
MWA's water supply reliability is anchored by a diverse portfolio that includes SWP allocations, natural and managed groundwater, imported wastewater, return flows, and strategically stored water supplies totaling over 250,000 acre-feet. This diversity provides crucial flexibility in responding to varying hydrological and regulatory conditions, though it also introduces complex interdependencies that require sophisticated risk management approaches.

As both SWP contractor and MBA Watermaster, MWA must navigate the intersection of imported water reliability—in which average delivery projections have declined an estimated 22% over the last 20 years—with local groundwater management obligations under multiple court judgments. The Agency's stored SWP water assets serve as a critical buffer, enabling the system to maintain reliability even during extended drought periods when imported supplies may be curtailed.

Still, MWA's water supply portfolio faces a range of threats that require comprehensive risk assessment and mitigation planning, including SWP operational and regulatory constraints, local infrastructure vulnerabilities, climate change-driven hydrological variability, extended drought scenarios, seismic risk, and other emerging challenges that could impact the Agency's ability to reliably meet regional water demands through the planning horizon.

6.4.5 Evaluating Future Risk Scenarios
MWA's reliability risk management operates within an increasingly complex regulatory environment, requiring coordination with Groundwater Sustainability Plans under the Sustainable Groundwater Management Act (SGMA), compliance with updated Urban Water Management Planning Act requirements, integration with local hazard mitigation planning, and compliance with statutes and authorities protecting federally endangered and threatened species under the Endangered Species Act (ESA), D-1641 Bay Delta Water Quality Control Plan, and California Endangered Species Act (CESA), among others.

Climate change introduces additional layers of complexity to traditional reliability planning.

Regional temperature data shows gradual warming trends over the past century, potentially increasing evapotranspiration rates and water demand pressures. While the high desert climate already experiences extreme conditions that limit the impact of incremental change, MWA recognizes the need to incorporate climate vulnerability assessment into long-term planning frameworks.

The significant risks to MWA’s water supplies mainly relate to sustained reductions in SWP deliveries. The SWP’s own climate adaptation planning, addressing more intense flood and drought cycles and rising sea levels in the Delta, directly impacts MWA's imported supply reliability. The DWR Delivery Capability Report, as discussed previously, indicates the expectation that the long-term average of the SWP deliveries will decrease. This trend of predicted long term average reductions has occurred in previous Delivery Capability Reports as well, and it is clear DWR plans to manage the SWP along these expectations. Even as projects like the Delta Conveyance Project are proposed to alleviate some of this supply reduction, it is only expected to mitigate reductions in supply rather than eliminate or even just stabilize the trend.

The most significant risk in the immediate future would be a sustained drought. If a multi- year severe drought were to impact SWP supplies and the MWA service area simultaneously, MWA would face a period with minimal capacity to recharge groundwater coupled with significant demand from within the service area that would strain basin health. Additionally, groundwater overdraft has led to ground subsidence along certain parts of SWP infrastructure, and while SMGA aims to mitigate subsidence and its impacts to the infrastructure, several groundwater basins across the State are still not in compliance and place the infrastructure at continued risk.

Seismic risks must also be considered in water supply reliability planning. Earthquakes put SWP infrastructure at risk, including dams, pumping plants, aqueducts, tunnels, and pipelines, many of which are located in seismically active parts of the state. Cascading risk such as fire from broken gas or electrical lines and flood risk from damaged dams or levees are also of concern. For instance, a major earthquake in the Bay Area that caused levee failure in the Delta could cause a catastrophic outage of water deliveries that could last for months or longer while repairs were made and salinity levels were restored. Seismic risks to critical infrastructure and potential supply disruptions require seismic monitoring and preparedness, infrastructure improvements, and comprehensive emergency response planning and system hardening strategies.

Water supply infrastructure within the MWA service area also poses potential risks to water deliveries. Significant portions of MWA’s pipelines face corrosion challenges, and repairs or replacement could reduce service capacities and the ability to take SWP water deliveries for groundwater recharge. Capital improvement projects must also be aligned to prevent artificial constraints on MWA supplies. Additionally, certain assets face other technical or biological constraints, such as water imports that could impact the Arroyo Toad or debris in the California Aqueduct limiting the ability to take water. These are systemic issues that impact the reliability of MWA’s water supplies but are manageable with foresight and prioritized action.

Sub-Chapter 6.5 – Managed
Groundwater Storage
As previously indicated, managed groundwater storage represents a critical component of water supply reliability across the Mojave Region, encompassing both the five MBA Judgment subareas and the Morongo Basin. MWA directly stores imported water in the MBA subareas, accounted for as “Managed Groundwater Storage,” and in the Morongo Basin under two separate agreements in the Ames Valley Basin and Warren Valley Basin.

Based on the most recent reporting, MWA maintains approximately 256,000 acre-feet of stored groundwater within the Mojave Basin Adjudication subareas, with an additional 173 acre-feet stored in the Morongo Basin under separate agreements. 42 6.5.1 Alto Subarea
The Alto Subarea storage account balance is approximately 194,000 acre-feet. The Alto Subarea above the Lower Narrows continues to serve as the largest repository of MWA's stored groundwater. Operating parameters have been established with a minimum operating level based on 2016 storage conditions and a maximum level representing eight years of average annual consumptive use (approximately 55,000 acre-feet). Since 1996, the subarea has experienced significant storage depletion, with a cumulative change of -510,826 acre-feet through 2024, though recent years showed recovery with a positive change of 35,963 acre-feet in Water Year 2023-2024. Water levels exhibit seasonal variation near the Mojave River, with declining trends in heavily pumped areas, particularly in the western portion of the Regional Aquifer.

6.5.2 Centro Subarea
The Centro Subarea storage account balance is approximately 35,000 acre-feet. The Centro Subarea operates under defined parameters established since 1997. The minimum operating range reflects the lowest storage since establishment of the Judgment when the basin was considered healthy, with maximum levels representing five years of average annual 42 Planning, Resources, Engineering, and Operations Committee presentation, March 31, 2026.

consumptive use (approximately 18,000 acre-feet). The subarea demonstrated positive storage recovery in Water Year 2023-2024 with a net gain of 29,794 acre-feet.

6.5.3 Baja Subarea
The Baja Subarea storage account balance is approximately 25,000 acre-feet. The Baja Subarea faces ongoing challenges, having lost approximately over 500,000 acre-feet of groundwater storage since 1996. However, recent trends suggest potential stabilization, with indications that continued pumping at current or lower levels due to reduced agricultural operations may halt continuous depletion. Optimal operating parameters remain under development.

6.5.4 Este Subarea
The Este Subarea storage account balance is approximately 1,300 acre-feet. The Este Subarea appears to maintain natural balance, with water supply and use remaining balanced over the past 20 years based on water level data. The subarea achieved equilibrium in Water Year 2023-2024 with no net change in storage. While optimal operating parameters have not been formally established, the long-term stability suggests sustainable management under current conditions. MWA has developed demonstration groundwater recharge facilities in the subarea and is continuing geotechnical investigations to support future recharge basin development.

6.5.5 Oeste Subarea
The Oeste Subarea currently maintains no MWA stored water accounts but demonstrates natural balance between water production, supply, and outflow. Water level data indicates short-term stability, leading to a "no change in storage" designation for planning purposes.

MWA has installed monitoring wells and approved design of a pilot recharge basin on a 10- acre Agency-owned parcel.
43 Geotechnical investigations are also ongoing to identify optimal locations for future off-Mojave River recharge facilities.

6.5.6 Morongo Basin
Beyond the MBA subareas, MWA maintains strategic storage in the Morongo Basin through two separate agreements. Storage includes 173 acre-feet in the Ames-Reche Management Area but zero acre-feet in Joshua Basin. The Ames-Reche Agreement covers 95 square miles and involves multiple agencies including Bighorn Desert View Water Agency and Hi-Desert Water District. Since 2012, water levels across the Ames-Reche Management Area have remained relatively stable, with annual pumping around 1,200 acre-feet compared to the 43 MWA Watermaster 2023-2024 Supply Conditions Report at p. 16.

established baseline of 1,646 acre-feet per year. The Warren Valley Basin within the Morongo area benefits from imported water deliveries through the Morongo Basin Pipeline, supporting both the Warren Valley Basin Judgment requirements and enhanced storage management.

Water levels have generally increased since implementation of recharge and management actions.

6.5.7 Summary of Managed Groundwater Storage by
Subregion
When organized into the three Subregions discussed in Chapter 2 – The Mojave Region, the Managed (Stored) Groundwater Storage is:

Subregion 1: 194,000 AF (Alto) + 1,300 AF (Este) + 0 AF (Oeste) = 195,300 AF Subregion 2: 35,000 AF (Centro) + 25,000 AF (Baja) = 60,000 AF Subregion 3: 173 AF (Ames) = 173 AF
While no formal minimum storage target has been set by MWA, this supply is viewed as a vital contingency source for potential repeating instances of very low SWP Table A Allocations in consecutive years – or for other drivers impacting the current year’s SWP Table A availability. As such, this source is recognized as available to meet Subregional demands whenever native groundwater (e.g. FPA for parties subject to the MBA Judgment), local recycled supplies, and anticipated Table A supplies are insufficient.

This supply is also available to help retail suppliers meet demands during future periods where demand may exceed the supply shown in their retail chapters in interim years but fall within the total 2050 supply shown in this RUWMP. Overall, use of this supply is represented within this RUWMP by making these supplies available in forecast supply tables for multiple dry year supply reliability in any event where a shortfall in Table A, native groundwater, or recycled water is projected prior to the use of the managed storage (see Chapter 5 – Regional Water Service Reliability).

6.5.8 Water Quality
This subsection focuses on the quality of State Water Project supplies imported into the region and recharged into the various portions of the groundwater basins and adjudicated areas throughout the Mojave Region. A discussion of groundwater quality is included in Chapter 3 – Regional Water Supply Characterization.

The quality of imported surface water conveyed through the California Aqueduct is monitored by the DWR Division of Operations and Maintenance. DWR maintains 16 continuous water quality monitoring stations located throughout the SWP and data collected from these stations is regularly updated to the California Data Exchange Center (CDEC). The parameters for monitoring SWP water quality include electrical conductivity, water temperature, turbidity,

pH, and fluorescence. SWP water quality changes as the water moves from precipitation and snowmelt runoff in Northern California to its termination points in Southern California. As such, the water quality measurements at each station are important for purposes of tracking water quality constituents in the SWP system.

Of the 16 water quality monitoring stations, Check 66 is located closest to MWA’s turnouts and Check 41 is examined to align operational decisions and data monitoring. Check 66 is located at an elevation of 3,448 feet in San Bernardino County near the City of Hesperia in the South Lahontan Hydrologic Region (see Figure 2-7). Figures 6-2 through 6-4 show the measured publicly available electrical conductivity, temperature, and turbidity at Check 66 since 2015 through 2025. Figure 6-5 shows pH at the Check 41 Kern measurement location and Figure 6-6 shows fluorescence at the Pacheco Pumping Plant.
44 FIGURE 6-2: CHECK 66 ELECTRICAL CONDUCTIVITY 2015-2025

44 These varying water quality monitoring station locations were chosen because Check 66 does not collect these water quality parameters and the Kern location (Check 41) and Pacheco Pumping Plant monitoring stations were the nearest to Check 66.

FIGURE 6-3: CHECK 66 WATER TEMPERATURE 2015-2025

FIGURE 6-4: CHECK 66 WATER TURBIDITY 2015-2025

FIGURE 6-5: CHECK 41 (KERN) PH VALUE (2015-2025)

FIGURE 6-6: PACHECO PUMPING PLANT FLUORESCENCE 2015-2025

6.5.9 Recycled Water Supplies
MWA is not directly involved with the creation or distribution of recycled water supplies. This activity does occur within a few of the retailer’s service areas, notably Hesperia Water District and the City of Victorville. MWA has zero recycled water supplies nor forecasts for such supplies.

6.5.10 Desalination Opportunities
The California UWMP Act requires a discussion of potential opportunities for use of desalinated water (Water Code Section 10631[i]). This discussion takes place in Section 3.1.3 of Chapter 3 – Regional Water Supply Characterization.

6.5.11 Water Transfers and Exchanges
MWA engages in water transfers and exchanges involving its SWP assets and other SWP Contractors’ SWP assets. Historically, MWA has both received and delivered water through these transfers and exchanges with various agencies throughout California. These transfers are essentially spot market transfers where short-term opportunities are identified and then actions taken for purchase and acquisition. These transfers help support management of MWA’s and its retail agencies’ water supply portfolios. Future MWA transfers and exchanges depend upon allocations available to MWA and other water purveyors and are not considered an available supply for purposes of this RUWMP.

6.5.12 Supply Summary
Mojave Water Agency operates a diverse and strategically managed water supply portfolio that serves over 500,000 residents across a 4,900-square-mile service area. As both a SWP contractor and MBA Watermaster, MWA's water supply strategy centers on importing surface water for groundwater recharge to support sustainable management of local groundwater basins.

MWA’s water supply portfolio consists of four primary components that work together to provide reliable water service through varying hydrological conditions. SWP imports form the foundation of MWA's supply strategy, with a maximum annual Table A contract amount of 89,800 acre-feet delivered through six turnout locations on the East Branch of the California Aqueduct. These imported supplies are primarily used for groundwater recharge rather than direct service delivery, supporting the adjudicated basin management framework that governs regional water use.

This integrated portfolio enables MWA to maintain water supply reliability across normal, single dry year, and multiple dry year conditions. The Agency's water supply diversification includes annual imported water deliveries combined with strategically managed locally

stored groundwater as well as SWP carryover supplies. A summary of MWA’s water supply portfolio is shown in Table 6-5.

TABLE 6-5: MWA WATER SUPPLY PORTFOLIO SUMMARY
Source Annual Amount Description
State Water Project – Table A 89,800
Maximum Table A contract amount;
actual deliveries vary (46% average
2010-2025)
SWP – Article 21 Variable Intermittent SWP surplus water when available
SWP – Article 56 Carryover Variable Stored SWP allocation in San Luis Reservoir
Managed Groundwater Storage 256,00045
Storage across Mojave Basin
subareas and Morongo Basin

For purposes of this RUWMP, the forecast of MWA’s SWP supplies are presented in Table 6-6 and Table 6-7.

TABLE 6-6: MWA’S PROJECTED SWP SUPPLY FOR 2026 – 2030 (AFY) Year SWP Contract Table A Percent Allocation Allocation Amount Normal 89,800 54% 48,492
Single Dry 89,800 5% 4,490
Multi-Year
Drought
2026 (1st year) 89,800 35% 31,430
2027 (2nd year) 89,800 5% 4,490
2028 (3rd year) 89,800 5% 4,490
2029 (4th year) 89,800 20% 17,960
2030 (5th year) 89,800 35% 31,430

45 March 2026 State Water Project Allocation and Imported Water Operations Plan Update, Presentation on March 31, 2026 to the Planning, Resources, Engineering, and Operations Committee.

TABLE 6-7: MWA’S PROJECTED SWP SUPPLY THROUGH 2050 (AFY) Total Supply Percent
Allocation 2030 2035 2040 2045 2050
Normal 54% 48,492 48,492 48,492 48,492 48,492
Single Dry Year 5% 4,490 4,490 4,490 4,490 4,490
Multi-Year
Drought
Year 1 35% 31,430 31,430 31,430 31,430 31,430
Year 2 5% 4,490 4,490 4,490 4,490 4,490
Year 3 5% 4,490 4,490 4,490 4,490 4,490
Year 4 20% 17,960 17,960 17,960 17,960 17,960
Year 5 35% 31,430 31,430 31,430 31,430 31,430

The characterizations of MWA’s SWP Table A Allocation long-term reliability reflect numerous hydrological and regulatory issues that inform the State’s DCR modeling, are reasonable assessments related to SWP system management, and reflect MWA’s local conditions. Long- term water management hydrological and regulatory issues include the Bay-Delta Water Quality Control Plan, the Coordinated Operations Agreement, the Delta Biological Opinion, the Delta Conveyance Project, modifications to San Luis Reservoir, SWP seismic considerations, DWR’s Emergency Planning, and assessments related to MWA’s local groundwater conditions and climate. MWA thoughtfully engages on all these issues and undertakes actions that help mitigate supply related impacts that may be caused by one or more listed items. These issues are all considered in MWA’s planning and incorporated into its supply characterizations in this RUWMP.

6.5.13 Groundwater within the Remaining Areas of the
Mojave Region
Besides its primary role as an importer of SWP supplies, MWA provides the geographic representation for the use of groundwater throughout the rest of the Region that is outside the service areas of the participating RUWMP retailers. The demand for water mostly reflects the other small retail water suppliers, rural domestic users, agricultural users, and large and small industries that are subject to the MBA Judgment.

Like to the other retail agencies, these users pump groundwater from the adjudicated MBA, specifically in Subregion 1 and Subregion 2 (see Figure 2-3). As discussed elsewhere, the basins used to meet these demands are recharged through several means, including natural recharge from the Mojave River, lateral subsurface groundwater movement from the adjacent San Gabriel mountains, imported water from the State Water Project (managed by MWA), and other sources like irrigation runoff, return flows from septic systems and water

delivery systems, and treated wastewater effluent. A detailed description of the MBA, Subareas, aquifer characteristics, adjudication, management areas, and other adjudicated basins is presented in Chapter 2 – The Mojave Region.

6.5.13.1 Mojave Region’s Remaining Free Production
Allowance
Under the MBA Judgment, each producer is assigned a Free Production Allowance (FPA), representing the annual quantity of groundwater that may be extracted without replacement obligations. The FPA for each participating retail water supplier is discussed and quantified for near- and long-term forecasts in each of their respective Chapters. For the remaining areas of the Mojave Region not part of the retail service areas, particularly in Subregion 1 and Subregion 2, there is a cumulative FPA that represents the near- and long-term FPA available to meet all these other users and uses. This groundwater is not controlled directly by MWA as a water supply but is managed through MWA’s role as the MBA Watermaster and represented in determinations of Base FPA.

For purposes of fully representing available FPA, this subchapter uses recent FPA quantities as they are presented by the MBA Watermaster in recent reports. Specifically, the forecast availability of native groundwater is determined by removing the retailer-specific FPA from the MBA Watermaster report for Base FPA.
46 This value, along with the representation of MWA’s
imported supply, is reflected in the water supply summary tables presented in Chapter 3 – Regional Water Supply Characterization.

Subregion 1 – Total annual Base FPA is approximately 70,400 acre-feet. Total RUWMP Retailer FPA is approximately 38,000 acre-feet. Remaining Base FPA is approximately 32,300 acre-feet.

Subregion 2 – Total annual Base FPA is approximately 39,600 acre-feet. Total retailer FPA is approximately 8,050 acre-feet. Remaining Base FPA is approximately 31,500 acre- feet.

46 Water Year 2024-2025 Watermaster Report, Appendix B-Summary, p. 15 of 16.

Sub-Chapter 6.6 – Water Use
Characterization
This sub-chapter describes the methodology used to forecast water demands within MWA’s service area that occur outside the service area boundaries of the ten participating urban water retail suppliers addressed in Chapters 7 through 16. These demands include small water systems, rural domestic users, agricultural uses, industrial uses, and golf course and recreational uses that are not otherwise quantified in the individual retailer chapters. Because MWA’s service area is concurrent with the Mojave Region, these demands are part of the overall regional water use forecast and are necessary to evaluate MWA’s wholesale water supply planning responsibilities.

Current regional water use, including use by participating urban water retail suppliers and other water users within the Mojave Region, is summarized in Section 4.4.1 – Current Regional Water Use of Chapter 4 – Water Use Characterization. Section 4.4.1 presents recent water use by major category and subregion and provides the current-use accounting used for the regional demand analysis. To avoid duplicating these tables and descriptions, this sub- chapter focuses on the methodology used to project future demands for small water systems and rural domestic users, industrial uses, golf course, recreational uses, and agricultural uses outside the service areas of the participating RUWMP retailers.

The resulting forecasts are incorporated into the regional demand summaries presented in Chapter 4 – Water Use Characterization and carried forward into Chapter 5 – Regional Water Service Reliability. Accordingly, this sub-chapter does not repeat the regional demand totals presented in Chapter 4 or the retailer-specific forecasts presented in Chapters 7 through 16.

Instead, it presents the other-use demand forecasts developed for MWA’s wholesale planning purposes and documents the assumptions, data sources, and methods used to develop those values. When combined with the applicable retailer forecasts, these other-use demands form the basis for the Subregion and Regional demand totals summarized in Tables 4-5 through 4-8.

6.6.1 Forecasting Water Demands Outside Participating
Retailer Service Areas
Small retail water supplier and rural domestic uses, agricultural uses, industrial uses, recreational uses, and golf course uses were forecast separately from the demands

developed for the participating urban water retail suppliers. For the adjudicated portions of MWA’s service area, these categories are tracked and reported annually by the Mojave Watermaster by adjudicated subarea. The Watermaster-reported production data were used as the primary basis for characterizing historical use and developing future demand forecasts in Subregions 1 and 2.

The Morongo Subarea is not part of the MBA adjudication, and comparable Watermaster- reported production data are not available for water uses outside of Hi-Desert Water District and Joshua Basin Water District. Accordingly, small retail water supplier and rural domestic, agricultural, industrial, recreational, and golf course demands outside of those retailer service areas were estimated using best available planning-level information, including available supplier data, land use and spatial information, and demand assumptions developed as part of MWA’s broader demand analysis.

6.6.1.1 Small Water Systems and Rural Domestic Use
MWA’s service area includes small public water systems and rural domestic users located outside the service area boundaries of the participating urban water retail suppliers. Chapter 2 – The Mojave Region presents the overall population associated with MWA’s wholesale demand area; however, this sub-chapter focuses on the methodology used to translate that population into projected water demands. For the adjudicated portions of MWA’s service area, small water system and rural domestic use is tracked through Mojave Watermaster reporting. Water use for small public water systems is generally metered and reported, while use by small private pumpers, which primarily reflects rural residential domestic use, is estimated by the Mojave Watermaster. These data were used to characterize recent historical use and develop a representative per-capita demand factor.

Future demand for this user class within Subregions 1 and 2 was estimated by dividing the reported total water use by the associated small water system and rural domestic population. In 2025, this user class within Subregions 1 and 2 had an estimated population of approximately 72,023 and a total water use of 14,544 acre-feet, resulting in an estimated use factor of 178 gallons per capita per day, or approximately 0.20 acre-feet per person per year.

This use factor is generally consistent with values calculated using 2021 through 2024 data and was therefore determined to be representative of recent and future demand conditions for this user class.

In 2025, the small water system and rural domestic population within Subregion 3 was estimated at approximately 12,580. However, because the Morongo Subarea is not part of the Mojave Basin Area adjudication, no comparable Watermaster reporting framework exists to track small water system and rural domestic production outside the service areas of Hi- Desert Water District and Joshua Basin Water District. Thus, future demands for this user class in Subregion 3 were estimated by applying the 0.20 acre-foot per person per year use factor developed from Subregions 1 and 2 to the Subregion 3 small water system and rural domestic population projections.

The resulting demand forecast was developed by applying the representative 0.20 acre-foot per person per year use factor to the small water system and rural domestic population projections presented in Table 6-2. Projected demands for this user class are summarized by Subregion in Table 6-8 and rounded to the nearest 5 acre-feet.

TABLE 6-8: PROJECTED SMALL WATER SYSTEM AND RURAL DOMESTIC DEMAND 2030-2050 (AFY)

Helendale Community Services District represents a notable component of the small water system and rural domestic demand forecast in Subregion 1. In 2025, Helendale CSD accounted for approximately 13% of Subregion 1’s small water system and rural domestic demand. Although Helendale CSA does not currently meet the UWMPA reporting threshold and is therefore not required to prepare an individual UWMP, it is one of the larger small retail water suppliers within the Mojave Region and is approaching the statutory threshold for UWMP preparation. Appropriately, Helendale CSD was included in MWA’s wholesale demand forecast and coordinated during development of the RUWMP, but its demands are addressed within this MWA wholesale chapter rather than in a separate retailer chapter.

6.6.1.2 Agricultural Use
Like the majority of groundwater users governed by the MBA Adjudication, agricultural users are assigned an FPA that is monitored by the Mojave Watermaster. Agricultural use has historically represented one of the larger water use categories in the Mojave Region; however, agricultural demands have declined substantially over the past several decades as production has adjusted to the adjudication framework and changing land use conditions.

Watermaster Annual Production Reports prepared since the 2020 MWA Wholesale UWMP indicate that agricultural has continued to decline below levels previously projected, particularly in the Centro and Baja Subareas where some agricultural lands have converted to solar development.
47 For purposes of this 2025 RUWMP, the 2025 agricultural demand of approximately 14,500 acre-feet is considered representative of long-term planning conditions. Therefore, agricultural demands are held constant by Subregion through 2050. The resulting agricultural demand forecast, rounded to the nearest five acre-feet, is presented in Table 6-9. 47 Regional Agricultural Water Use from 2021 through 2025 is presented in Table 4-1.

Subregion 2030 2035 2040 2045 2050
Subregion 1 11,550 11,370 10,925 10,420 9,310
Subregion 2 2,805 2,760 2,650 2,530 2,260
Subregion 3 2,475 2,435 2,340 2,230 1,995

TABLE 6-9: PROJECTED AGRICULTURAL DEMAND 2030-2050 (AFY)

6.6.1.3 Industrial, Golf Course, and Recreational Uses
Industrial, recreational, and golf course uses outside the service area boundaries of the participating urban water retail suppliers were forecast separately from the small water system, rural domestic and agricultural demands. For the adjudicated portions of MWA’s service area, these uses are tracked by the Mojave Watermaster and reported in the Watermaster Annual Production Reports. Based on recent reporting, these use categories have shown modest declines between 2021 and 2025, with no identified growth trend or known development activity indicating a near-term increase in demand.

For purposes of this 2025 RUWMP, 2025 water use was determined to be representative of long-term planning conditions for industrial, recreational, and golf course uses. Accordingly, the 2025 demand values are held constant by subregion through 2050. For Subregion 3, demands outside the service area boundaries of Hi-Desert Water District and Joshua Basin Water District were estimated using publicly available aerial imagery, remote sensing data, and land use information as the Morongo Subarea is not subject to a centralized Watermaster reporting framework. The resulting demand forecast, rounded to the nearest five acre-feet, is presented in Table 6-10.

48 A spatial review using aerial imagery, remote sensing data, and land use information confirmed the no agricultural use in Subregion 3. This review was conducted because the Morongo Subarea is not subject to a centralized Watermaster reporting framework comparable to the MBA adjudicated subareas.

Subregion 2030 2035 2040 2045 2050
Subregion 1 3,000 3,000 3,000 3,000 3,000
Subregion 2 11,500 11,500 11,500 11,500 11,500
Subregion 348 0 0 0 0 0

TABLE 6-10: PROJECTED INDUSTRIAL, RECREATIONAL, AND GOLF COURSE DEMAND 2030-2050 (AFY) Subregion 2030 2035 2040 2045 2050
Industrial Subregion 1 4,400 4,400 4,400 4,400 4,400
Subregion 2 2,600 2,600 2,600 2,600 2,600
Subregion 3 335 335 335 335 335
Recreational Subregion 1 5,400 5,400 5,400 5,400 5,400
Subregion 2 1,800 1,800 1,800 1,800 1,800
Subregion 3 50 50 50 50 50
Golf Course Subregion 1 5,000 5,000 5,000 5,000 5,000
Subregion 2 0 0 0 0 0
Subregion 3 215 215 215 215 215

The forecasts presented in Tables 6-8 through 6-10 represent the water demand components within MWA’s service area that are outside the service area of the participating urban water retail suppliers. These forecasts are not intended to replace or duplicate the regional demand summaries presented in Chapter 4 – Water Use Characterization. Rather, they provide the supporting other-use demand values that are combined with the applicable retailer demand forecasts to develop the Subregion and regional demand totals presented in Tables 4-5 through 4-8. The integrated regional demand forecast is then carried forward into Chapter 5 – Regional Water Service Reliability.

Sub-Chapter 6.7 – Water
Conservation and Shortage
Response
Pursuant to CWC Sections 10631(e) and 10632, this sub-chapter summarizes the MWA’s demand management measures and water shortage response framework. As a wholesale urban water supplier, MWA’s conservation and shortage response responsibilities differ from those of the participating retail water suppliers. MWA does not generally provide direct retail water service; rather, it supports regional water reliability through imported water management, groundwater recharge, stored water management, regional conservation coordination, and administration of adjudicated groundwater management responsibilities.

MWA’s demand management efforts are focused on supporting efficient regional water use, coordinating conservation messaging and programs with participating agencies, and maintaining long-term reliability of the groundwater supplies that serve the Mojave Region.

These efforts complement the retail-level demand management measures implemented by the participating urban water retail suppliers within their respective service areas.

MWA’s Water Shortage Contingency Plan (WSCP), adopted with the 2020 UWMP and readopted as part of this 2025 RUWMP, provides the Agency’s framework for evaluating water supply conditions and responding to potential shortages. The WSCP addresses water supply reliability, Annual Water Supply and Demand Assessment procedures, six standard shortage levels, shortage response actions, communication protocols, legal authorities, financial considerations, reevaluation procedures, and plan adoption and availability. Because MWA’s role is regional and wholesale in nature, implementation of the WSCP emphasizes coordination with retail water agencies, management of available imported and stored supplies, and actions to mitigate extended drought conditions or catastrophic interruptions to regional water supply availability.

No substantive changes have been made to MWA’s 2020 WSCP for purposes of this 2025 RUWMP. However, the water supply reliability analysis, demand forecasts, drought risk assessment, and related planning assumptions have been updated through the 2025 RUWMP. Accordingly, the WSCP remains applicable as MWA’s shortage response framework, while the updated reliability findings presented in this chapter and in Chapter 5 – Regional

Water Service Reliability provide the current basis for evaluating supply conditions over the planning horizon.

A complete description of MWA’s WSCP, including detailed implementation procedures and supporting documentation, is provided in Appendix 4.

6.7.1 Demand Management Measures
MWA has implemented a broad set of demand management measures (DMMs) to promote efficient use of water resources and support long-term regional water supply reliability.

Because MWA functions primarily as a wholesale water supplier, State Water Project contractor, and regional groundwater management agency, its DMMs differ from those implemented by retail water suppliers. MWA does not generally provide direct retail water service or regulate day-to-day customer water use within the service areas of participating urban water retail suppliers. Instead, MWA’s DMMs focus on regional conservation coordination, public education and outreach, technical support, water use efficiency programs, regional supply planning, and management of imported and stored water supplies.

MWA’s DMMs are implemented in coordination with participating retail agencies, small water systems, rural domestic users, and other regional water users. These efforts complement the retail-level DMMs described in the individual retailer chapters of this RUWMP and help provide a consistent regional framework for water conservation, efficient water use, and long-term reliability planning.

MWA will continue to implement and refine its DMMs to support efficient water use, regional water supply reliability, and compliance with applicable State requirements. Additional information regarding MWA’s foundational, recent, and planned DMM activities is provided in the following subsections.

6.7.2 Foundational Demand Management Measures
MWA’s foundational DMMs remain generally consistent with those described in the 2020 UWMP and continue to serve as the basis for regional conservation and water use efficiency efforts. These measures include metering of imported water deliveries, public education and outreach, conservation program coordination and staffing support, distribution system asset management for MWA-owned facilities, and wholesale supplier assistance.

Water Measurement and Accounting
MWA measures State Water Project deliveries received through its turnouts and tracks water delivered to recharge, recovery, and other Agency-managed facilities. These data support regional water accounting, operational planning, and long-term supply reliability analyses.

Public Education and Outreach
MWA implements public education and outreach programs to promote efficient water use throughout the Mojave Region. These efforts include conservation messaging, educational materials, public presentations, workshops, community events, and coordination with regional partners such as the Alliance for Water Awareness and Conservation.

Conservation Program Coordination and Staffing Support
MWA supports regional conservation through dedicated program coordination, staffing, and funding. These efforts include technical and administrative support for conservation programs, participation in regional events and conferences, and support for rebate, education, and outreach activities that encourage efficient water use across the Region.

MWA-Owned Facility Management
MWA operates and maintains facilities associated with imported water delivery, recharge, recovery, and regional water supply management. MWA monitors and maintains these facilities to support reliable operations, accurate flow measurement, water quality compliance where applicable, and efficient use of imported and stored water supplies.

Wholesale Supplier Assistance
MWA provides technical, financial, and programmatic assistance to retail suppliers and regional partners to support conservation and water-use efficiency. This assistance includes coordination through regional conservation programs, support for public information and education efforts, and implementation of programs that help retail suppliers and their customers reduce demand where appropriate.

6.7.2.1 Recent DMM Activities
Since the 2020 UWMP, MWA has continued to implement regional conservation, education, and coordination activities. These efforts have included continued public outreach, regional conservation messaging, coordination with participating retail agencies, support for conservation programs, and development of updated regional planning analyses through the 2025 RUWMP.

6.7.2.2 Planned DMM Activities
MWA will continue implementing DMMs that reflect its wholesale and regional water management role. Planned activities include continued coordination with participating retail agencies, ongoing public education and outreach, support for regional conservation programs, continued measurement and accounting of imported and stored supplies, and maintenance of MWA-owned facilities needed to support long-term regional water supply reliability.

6.7.3 Water Shortage Contingency Plan
MWA has adopted a WSCP in accordance with CWC Section 10632. The WSCP establishes a structured framework for evaluating regional water supply conditions, coordinating with retail water suppliers, and implementing appropriate response actions during drought, constrained imported water conditions, or other supply interruptions. Because MWA functions as a wholesale water supplier, SWP contractor, and regional groundwater management agency, the WSCP is focused on regional supply management and coordination rather than direct regulation of retail customer water use.

6.7.3.1 Summary of Water Shortage Levels and Response
Actions
MWA’s WSCP includes six standard shortage stages corresponding to progressively severe shortage conditions of up to 10%, 20%, 30%, 40%, 50% and greater than 50%. These stages provide a consistent framework for evaluating the relative severity of regional supply constraints. However, unlike retail shortage stages, MWA’s stages are implemented primarily through wholesale and regional water management actions, including use of stored supplies, access to flexible or alternative supplies, coordination of voluntary demand reduction messaging, and operational adjustments to MWA facilities, including R-Cubed deliveries where appropriate.

Stage 1 – Up to 10% Shortage:

During Stage 1, MWA may access stored supplies, as needed, to address supply deficits. MWA may also coordinate voluntary conservation messaging with retail agencies, public agencies, and the broader community to encourage efficient water use and communicate the potential for future shortage conditions.

Stage 2 – Up to 20% Shortage:

During Stage 2, MWA may continue to access stored supplies while increasing coordination with retail agencies. MWA may also implement voluntary demand reduction messaging and reduce R-Cubed deliveries, as appropriate, to help align supply availability with projected demands.

Stage 3 – Up to 30% Shortage:

During Stage 3, MWA may intensify regional coordination, continue use of stored supplies, and further evaluate operational adjustments to MWA-managed facilities. R- Cubed deliveries may be reduced in coordination with affected retail agencies, while voluntary demand reduction messaging may be expanded to address increased severity of the shortage condition.

Stage 4 – Up to 40% Shortage:

During Stage 4, MWA may continue to rely on stored supplies, voluntary demand reduction, and reduced R-Cubed deliveries as appropriate. At this stage, MWA would evaluate regional supply conditions, operational constraints, and available management actions to preserve stored water assets and maintain reliability for essential regional needs.

Stage 5 – Up to 50% Shortage:

During Stage 5, MWA may implement more intensive regional supple management actions, including increased reliance on stored supplies, pursuit of alternative supplies, and continued operational coordination with retail agencies. MWA may also further reduce R-Cubed deliveries where appropriate and expand regional communication regarding shortage conditions and available response actions.

Stage 6 – Greater than 50% Shortage:

During Stage 6, MWA would implement emergency-level regional supply management actions necessary to address severe shortage conditions or catastrophic supply interruptions. These actions may include use of available stored supplies, pursuit of alternative supplies or transfers, operational adjustments to MWA facilities, reduction of R-Cubed deliveries, and close coordination with retail agencies, DWR, SWP contractors, and other regional partners to support continued water supply reliability for essential needs.

6.7.3.2 Summary of Monitoring Procedures and
Implementation
MWA conducts an Annual Water Supply and Demand Assessment each year in accordance with CWC requirements. These assessments are prepared and submitted to DWR by July 1 and evaluate anticipated regional water supply and demand conditions over a rolling twelve-month period spanning July through June. The Annual Assessment serves as the primary mechanism for evaluating near-term supply reliability and determining whether implementation of one or more WSCP shortage stages may be warranted.

MWA has completed and submitted an Annual Assessment each year since 2022, as required by statute. While the results of these assessments are not included in this RUWMP, the methodology and demand assumptions applied are consistent with those presented in this chapter and in Chapter 5 – Regional Water Service Reliability. The Annual Assessment considers available regional supplies, projected demands, infrastructure capability, imported water availability, stored water assets, and other locally applicable factors that may influence water supply reliability.

Implementation of the WSCP relies on coordination among MWA staff, retail water suppliers, regional partners, stakeholders, and the public. During shortage conditions, MWA may

communicate regional supply conditions, shortage stage determinations, available response actions, and recommended coordination measures to retailer water suppliers, regional partners, stakeholders, and the public. This approach supports consistent messaging while allowing retail suppliers to implement customer-level shortage response actions within their respective service areas.

Sub-Chapter 6.8 – Water System
Reliability and Drought Risk
Assessment
MWA’s water system reliability and drought risk assessment findings are presented in Chapter 5 – Regional Water Service Reliability. The reliability analysis is informed by the MWA-specific supply and operational information presented in this chapter, including imported water supply availability and reliability considerations described in Sub-Chapter

6.4, managed groundwater storage described in Sub-Chapter 6.5, and MWA’s wholesale demand forecast for uses outside the participating retail supplier service areas described in Sub-Chapter 6.6. These MWA-specific inputs are combined with the regional supply characterization presented in Chapter 3 – Regional Supply Characterization and the regional water use forecast presented in Chapter 4 – Water Use Characterization to evaluate regional reliability under the UWMPA-required considerations. Chapter 5 integrates these assumptions to satisfy the applicable water system reliability and drought risk assessment requirements, including the Five-Year Drought Risk Assessment, normal year, single dry year, and five consecutive dry year analyses through 2050.

The results demonstrated in Chapter 5 demonstrate that the Mojave Region’s water supply portfolio is capable of meeting the water uses in the Region in normal, single dry, and five consecutive dry years from 2025 through 2050.

Sub-Chapter 6.9 – Energy Intensity
Analysis
Pursuant to CWC Section 10631.2, this sub-chapter summarizes energy use associated with MWA’s water management operations to the extent such information is readily available.

MWA’s energy reporting differs from a traditional retail water supplier because the Agency does not generally operate a retail potable water distribution system or deliver water directly to end-use customers. Instead, MWA’s primary operations consist of importing SWP supplies, conveying water to recharge locations, placing water into groundwater storage, and managing regional water supply reliability. Accordingly, the energy information presented in this sub-chapter focuses on MWA-controlled water management processes for which energy and water volume data are readily obtainable, including conveyance, recharge, recovery, and related operations, as applicable.

The principal exception to MWA’s recharge-focused operating model is the Regional Recharge and Recovery Project, or R-Cubed, which stores imported supplies in the Floodplain Aquifer and, when needed, recovers and delivers that water through MWA-owned wells and pipelines directly to participating retail water suppliers. Because R-Cubed includes recovery and direct delivery components, its energy use is included in MWA’s energy evaluation where data are readily available.

T
ABLE 6-11: ENERGY INTENSITY – TOTAL UTILITY APPROACH FOR MONTH YEAR THROUGH MONTH YEAR Sum of All Water Management Processes
Volume of Water Entering Process (acre-feet)
Energy Consumed (kWh)
Energy Intensity (kWh/acre-foot)

Chapter 7.0 THE CITY OF ADELANTO

This page is reserved for Chapter 7 – The City of Adelanto. The complete City of Adelanto retail specific chapter is included in the full 2025 Mojave RUWMP and is adopted separately by the City of Adelanto.

Chapter 8.0 COUNTY SERVICE AREA
64 SPRING VALLEY LAKE

This page is reserved for Chapter 8 – County Service Area 64 Spring Valley Lake. The complete County Service Area 64 Spring Valley Lake retail specific chapter is included in the full 2025 Mojave RUWMP and is adopted separately by the County of San Bernardino.

Chapter 9.0 COUNTY SERVICE AREA
70J OAK HILLS

This page is reserved for Chapter 9 – County Service Area 70J Oak Hills. The complete County Service Area 70J Oak Hills retail specific chapter is included in the full 2025 Mojave RUWMP and is adopted separately by the County of San Bernardino.

Chapter 10.0 GOLDEN STATE WATER
COMPANY – BARSTOW SYSTEM

This page is reserved for Chapter 10 – Golden State Water Company – Barstow System. The complete Golden State Water Company – Barstow System retail specific chapter is included in the full 2025 Mojave RUWMP and is adopted separately by the Golden State Water Company.

Chapter 11.0 HESPERIA WATER

DISTRICT

.

TABLE OF CONTENTS
Sub-Chapter 11.1 – Introduction .................................................................................................................................................................. 11-7

11.1.1 Background and Purpose ...................................................................................................................................................... 11-7

11.1.2 Basis for Plan Preparation ..................................................................................................................................................... 11-8

11.1.3 Coordination and Outreach ................................................................................................................................................ 11-8

11.1.4 RUWMP Adoption ......................................................................................................................................................................... 11-9

11.1.5 Document Organization ....................................................................................................................................................... 11-10 Sub-Chapter 11.2 – Water Service and System Description..................................................................................................... 11-11

11.2.1 Service Area Climate ............................................................................................................................................................... 11-13 Sub-Chapter 11.3 – Population, Land Use, Economy, and Demographics .................................................................... 11-14

11.3.1 Current Population and Historic Trends ..................................................................................................................... 11-14

11.3.2 Projected Population .............................................................................................................................................................. 11-15

11.3.3 Current and Projected Land Use ..................................................................................................................................... 11-16

11.3.4 Economic Trends & Other Social and Demographic Factors ...................................................................... 11-19 Sub-Chapter 11.4 – Water Supply and Infrastructure Characterization ....................................................................... 11- 20

11.4.1 Groundwater ............................................................................................................................................................................... 11- 20

11.4.2 Groundwater Quality ............................................................................................................................................................. 11- 24

11.4.3 Recycled Water Supplies .................................................................................................................................................... 11- 26

11.4.4 Desalination Opportunities ................................................................................................................................................ 11- 28

11.4.5 Water Transfers and Exchanges .................................................................................................................................... 11- 28

11.4.6 Supply Summary ...................................................................................................................................................................... 11- 29

11.4.7 Delivery System Details .......................................................................................................................................................... 11- 31 Sub-Chapter 11.5 – Water Use Characterization .......................................................................................................................... 11- 32

11.5.1 Current Customer Water Use........................................................................................................................................... 11- 33

11.5.2 Compliance with Water Use Targets and Objectives ....................................................................................... 11-37

11.5.3 Forecasting Customer Use ................................................................................................................................................ 11- 38

11.5.4 Forecasting Water Use for DRA and Annual Assessment .............................................................................. 11- 41

11.5.5 Projecting Disadvantaged Community Water Use ........................................................................................... 11- 43 Sub-Chapter 11.6 – Water Conservation and Shortage Response ................................................................................. 11-44

11.6.1 Demand Management Measures ................................................................................................................................ 11- 44

11.6.2 Foundational Demand Management Measures ................................................................................................ 11- 45

11.6.3 Water Shortage Contingency Plan............................................................................................................................... 11- 47 Sub-Chapter 11.7 – Water System Reliability and Drought Risk Assessment ............................................................ 11-50

11.7.1 Five-year Drought Risk Assessment ............................................................................................................................ 11- 50

11.7.2 Long-Term Service Reliability ........................................................................................................................................... 11- 51

11.7.3 Annual Reliability Assessment ........................................................................................................................................ 11- 53

11.7.4 Water Supply Reliability Summary ............................................................................................................................... 11- 54 Sub-Chapter 11.8 – Energy Intensity Analysis ................................................................................................................................. 11- 55

LIST OF TABLES
Table 11-1: Public Water System Information ...................................................................................................................................... 11-8 Table 11-2: Customer Water Service Connections ......................................................................................................................... 11-12 Table 11-3: Historical Population ............................................................................................................................................................... 11-15 Table 11-4: Population Growth Rate - 2015-2024 ........................................................................................................................... 11-15 Table 11-5: Population Forecast and Growth Rate ........................................................................................................................ 11-16 Table 11-6: Known Land Use Plans in Service Area ........................................................................................................................ 11-17 Table 11-7: Last five years of Hesperia Water District's FPA Supply (AFY) ....................................................................... 11-21 Table 11-8: Projected Mojave Adjudication FPA for the District through 2030 (AFY) .............................................. 11-22 Table 11-9: Projected Mojave Adjudication FPA for the District through 2050 (AFY) .............................................. 11-22 Table 11-10: Last five years of Replacement and Make-up Water Supplies (AFY) .................................................. 11-23 Table 11-11: Hesperia Water District Potable Water Quality .................................................................................................... 11- 25 Table 11-12: Last five years of Recycled Water Supplies (AFY) .............................................................................................. 11-27 Table 11-13: Projected Recycled Water Supplies 2030 (AFY) .................................................................................................. 11-27 Table 11-14: Projected Recycled Water Supplies through 2050 (AFY) ............................................................................. 11- 28 Table 11-15: District's Managed Groundwater Production 2021-2025 (AFY) ................................................................ 11-29 Table 11-16: District's Projected Managed Groundwater Supply 2026-2030 (AFY) ................................................ 11-30 Table 11-17: District's Projected Managed Groundwater Supply through 2050 (AFY) ........................................... 11-30 Table 11-18: Potable Customer Use 2021-2025 (AF) .................................................................................................................... 11- 35 Table 11-19: Non-Potable Customer Use 2021-2025 (AF) ......................................................................................................... 11- 36 Table 11-20: Distribution System Loss 2021-2024 ........................................................................................................................... 11- 37 Table 11-21: Forecast Future Water Use (AFY) .................................................................................................................................. 11- 40 Table 11-22: Forecast DRA Water Use for 2026 through 2030 (AFY) ................................................................................. 11- 43 Table 11-23: Five-year Drought Risk Assessment (AFY) ............................................................................................................. 11- 51 Table 11-24: Normal and Single Dry Year Water Supply and Demand through 2050 (AFY) ............................ 11-52 Table 11-25: Five Consecutive Dry Years Water Supply and Demand through 2050 (AFY) ............................. 11-53 Table 11-26: Energy Intensity - Total Utility Approach for Oct 2024 through Sept 2025 ...................................... 11-55

LIST OF FIGURES
Figure 11-1: Hesperia Water District Service Area ............................................................................................................................ 11-12 Figure 11-2: Known Land Use Plans in Service Area Map ........................................................................................................... 11-18 Figure 11-3: Potable Water System ........................................................................................................................................................... 11- 31

APPENDICES
Appendix 7A- Hesperia Water District WSCP ..................................................................................................................................... A-5 Appendix 7B- Hesperia Water District DWR Checklist .................................................................................................................. A-6

Sub-Chapter 11.1 – Introduction
The Hesperia Water District (District) operates as a subsidiary special district of the City of Hesperia (City), and the City Council serves as the District’s Board of Directors. The City’s Water Department includes the following divisions: Water Production, Water Distribution, Water Pipeline, Sewer and Stormwater, and Customer Service and Meters.

The City of Hesperia, known as the “Gateway to the High Desert,” is situated just north of the San Bernardino Mountains and only 35 miles from downtown San Bernardino over the Cajon Pass. The City is in the Victor Valley at the foot of the north slope of the San Bernardino Mountains at an elevation of about 3,100 feet above sea level in the northern area, to about 4,000 feet in the south at the foot of the mountains. The City’s key planning objectives include responsible growth for its rural, suburban, agricultural, commercial, and industrial land uses, paired with economic development that attracts and maintains quality business and industry while being beneficial to its residents.

The District’s water supply is sourced almost entirely from groundwater pumped from the Mojave River Groundwater Basin, with a small portion of demand met through recycled water derived from that supply. Ensuring an adequate and reliable water supply for current and future customers is fundamental to the District’s mission. Through participation in the 2025 Mojave RUWMP (2025 RUWMP), the District supports coordinated, basin-wide planning.

Regional conditions and assumptions are presented in the 2025 RUWMP regional chapters, while this chapter focuses on District-specific system characteristics, demands, demand management measures, and reliability.

11.1.1 Background and Purpose
The District has ensured compliance with the Urban Water Management Plan Act (UWMPA) requirements for urban water suppliers through its participation in the 2025 RUWMP and preparation of this retail-specific chapter.
49 The UWMPA requires urban water suppliers to
evaluate the adequacy of their water supplies to meet projected demands under average conditions, single dry years, and multiple dry year scenarios through a 20-year planning horizon. This chapter presents the District’s evaluation of these requirements and demonstrates its ability to meet anticipated demands under normal and drought conditions.

The 2025 RUWMP, together with this retail-specific chapter, updates the District’s 2020 Urban Water Management Plan (UWMP) and incorporates new data, analyses, and regulatory 49 California Water Code Sections 10610 through 10657.

guidance issued since 2020 by the California Department of Water Resources (DWR) pursuant to the California Water Code (CWC). In addition to satisfying statutory requirements, the 2025 RUWMP serves as a comprehensive planning document describing existing and future water supplies, projected water demands, demand management progress, and actions necessary to maintain long-term supply reliability. The regional plan also documents cooperative efforts among participating agencies to efficiently manage shared resources and address future water needs across the RUWMP Planning Area.

11.1.2 Basis for Plan Preparation
The District operates a Public Water System as described in California Health and Safety Code Section 116275. The District is also classified as an Urban Water Supplier pursuant to CWC Section 10617, as it provides water for municipal purposes to more than 3,000 service connections and supplies more than 3,000 acre-feet of water annually. These qualifications require the preparation and adoption of a UWMP every five years. Under CWC Section 10620 (d)(1), these requirements may be satisfied through participation in a RUWMP, which the District and the other Urban Water Suppliers within the RUWMP Planning Area have elected to prepare collaboratively. Details of the District’s Public Water System are provided in Table 11-1.

T
ABLE 11-1: PUBLIC WATER SYSTEM INFORMATION
Public Water System Number Public Water System Name Number of Municipal Connections CA3610024 HESPERIA WATER DISTRICT ~29,205

11.1.3 Coordination and Outreach
Preparation of the 2025 RUWMP involved coordination among the participating Urban Water Suppliers and the Mojave Water Agency (MWA), which serves as the region’s wholesale water supplier. This coordination ensured consistency in assumptions, methodologies, and regional analyses. The District actively participated in this collaborative process through technical meetings, data sharing, and review of draft materials addressing both regional conditions and District-specific operations.

As required by the UWMPA, the District coordinated with nearby agencies during development of this chapter to ensure consistency with related land use and water resource planning efforts, including City General Plans, Water Master Plans, and Specific Plans associated with anticipated development.

Consistent with CWC Section 10641, the District encouraged active participation from a broad cross-section of the community representing diverse social, cultural, and economic interests within its service area during preparation of this chapter. Public notice of the plan’s

availability and the scheduled public hearing was provided, and a public hearing was conducted prior to adoption to solicit input from customers, stakeholders, and interested parties.

Comprehensive documentation of the regional planning process, including interagency coordination, formal notifications provided in accordance with CWC Section 10621(b), stakeholder engagement, and outreach activities conducted on behalf of all participating agencies, is provided in Sub-Chapter 1.1.3 Coordination and Outreach of Regional Chapter 1 - Introduction.

11.1.3.1 Water Supplier Information Exchange
Compliance with CWC Section 10631 is described in Sub-Chapter 1.1.3 Coordination and Outreach of Regional Chapter 1 – Introduction.

11.1.4 RUWMP Adoption
The District held a public hearing regarding the 2025 RUWMP on May 19, 2026. Before the hearing, the District made a draft of the 2025 RUWMP available for public inspection at City Hall, 9700 Seventh Avenue, Hesperia, CA 92345, and on the City’s website. Pursuant to CWC Section 10642, general notice of the public hearing was provided through publication of the hearing date and time in the local press as required under the UWMPA.

The District’s elected body adopted this 2025 RUWMP on May 19, 2026. A copy of the 2025 RUWMP will be submitted to DWR, provided to the County and the California State Library, and posted onto the City’s website.

The District plans to submit all required documentation related to the UWMPA through the DWR submittal website soon after adoption, including the on-line submittal of information associated with the following DWR Excel workbooks:
“FINAL Submittal 2025 UWMP Tables – Hesperia WD – 06.01.2026.xls” “Appendix F 2025 Checklist – Hesperia WD – 06.01.2026.xls”

11.1.5 Document Organization
This chapter is organized as follows:

Sub-Chapter 11.2 Water Service and System Description
Sub-Chapter 11.3 Population, Land Use, Economy, and Demographics Sub-Chapter 11.4 Water Supply and Infrastructure Characterization Sub-Chapter 11.5 Water Use Characterization
Sub-Chapter 11.6 Water Conservation and Shortage Response Sub-Chapter 11.7 Water System Reliability and Drought Risk Assessment Sub-Chapter 11.8 Energy Intensity Analysis

Sub-Chapter 11.2 – Water Service and
System Description
The Hesperia Water District provides potable water service to the residents and businesses within its service area, depicted in Figure 11-1, which largely coincides with the boundaries of the City of Hesperia.

Water service in the District relies entirely on groundwater extracted from wells located throughout the service area. The District manages 15 active wells that tap into local aquifers to provide the community’s water supply. Once extracted, water is treated to meet all applicable federal and state water quality standards and is either directed into the distribution system or stored in one of the District’s 14 reservoirs, which collectively provide more than 64 million gallons of storage. These reservoirs help ensure that the community has access to adequate water during periods of high demand, particularly in the summer months.

The District’s water system encompasses an extensive distribution network designed to deliver water efficiently to homes, businesses, and fire protection systems. The system includes over 600 miles of water mains, thousands of service connections, and thousands of valves and fire hydrants that allow the District to isolate portions of the system for maintenance or emergencies without disrupting service to the broader community. Table 11-2 summarizes recent historical service connections by customer type, providing an overview of the composition of the District’s customer base. The District also engages in regular inspection, maintenance, and replacement of system components to ensure long- term reliability and safety of the water supply.

The District has also developed a recycled water program to maximize local water resource resiliency. Recycled water produced within the District is treated to appropriate regulatory standards and used for non-potable purposes such as irrigation of parks, landscapes, and the Hesperia Golf Course. These efforts enhance local water reliability, conserve groundwater, and support sustainable water management throughout the community.

FIGURE 11-1: HESPERIA WATER DISTRICT SERVICE AREA

TABLE 11-2: CUSTOMER WATER SERVICE CONNECTIONS
Customer Class 2021 2022 2023 2024 2025
Single-Family Residential 25,639 25,875 26,054 26,237 26,802 Multi-Family Residential 528 531 532 529 527
Commercial/Institutional 1,031 1,039 1,047 1,053 1,064
Landscape Irrigation 122 129 137 143 161
Other 575 599 610 630 651
Total 27,895 28,173 28,380 28,592 29,205

11.2.1 Service Area Climate
Located in California’s Mojave Basin Area, the District’s service area experiences the climate characteristic of the High Desert. The region is highly arid due to the rain shadow effects of surrounding mountain ranges and is marked by hot summers and relatively cool winters. This results in low precipitation and pronounced diurnal temperature variations throughout the year. Average annual precipitation is minimal, with a 30-year average of 8.17 inches, occurring primarily as rainfall between December and March. Precipitation generally tapers off by May. While late summer monsoonal thunderstorms may contribute episodic precipitation, these events typically account for only a small portion of total annual precipitation. Although snowfall is rare, winter snowfall averages four inches annually. The annual average temperature is approximately 60 degrees Fahrenheit; however, the High Desert climate produces substantial seasonal extremes, with summer temperatures frequently exceeding 100 degrees and winter lows occasionally falling below freezing. Overall, the District’s service area climate is generally consistent with climatic conditions across the RUWMP Planning Area. A more detailed discussion of the RUWMP Planning Area’s climate characteristics is provided in Sub-Chapter 2.1.5 Climate of Regional Chapter 2 – The Mojave Region.

11.2.1.1 Climate Change
Climate change is driven by increasing concentrations of atmospheric carbon dioxide and other greenhouse gases, resulting in rising temperatures and greater hydrologic variability.

These effects underscore the importance of considering climate change in this 2025 RUWMP.

While the CWC does not prescribe specific climate change planning or management measures for retail water suppliers, it emphasizes that climate change is an appropriate consideration for general water management and planning. Accordingly, climate change is a critical factor in assessing the availability and reliability of water supplies, as well as future demand projections. A detailed discussion of climate change impacts on the District’s water supplies and demands, as well as those of the RUWMP Planning Area at-large, is provided in Sub-Chapter 2.1.5 Climate of Regional Chapter 2 – The Mojave Region.

Sub-Chapter 11.3 – Population, Land
Use, Economy, and Demographics
Service area population and land use projections are critical to developing a useful planning framework as population dynamics and growth are a primary influence on water use. These projections directly influence planning measures for system supply, delivery, infrastructure, and demand management. Similarly, understanding the service area’s economic, social, and demographic trends provide valuable insight into water management and planning. This sub-chapter addresses these factors to provide a supportable basis for forecasting future water use.

11.3.1 Current Population and Historic Trends
Population estimates for the District are based on the population forecast prepared in 2020 by the Center for Economic Forecasting and Development at the University of California, Riverside (UCR Study), which was commissioned by MWA as part of the 2020 Urban Water Management Plan cycle. The UCR Study developed population estimates for the entire MWA service area as well as for individual retailer water supplies using a comprehensive economic and demographic modeling approach.

In 2023, as part of MWA’s Master Plan development, the agency reviewed and refined the UCR Study population projections using updated information not available during the study’s development, including 2020 Census data and other available demographic indicators, to ensure that near-term population levels and growth patterns were accurately represented.

Where appropriate, adjustments were applied to align study estimates with observed population totals while maintaining the long-term growth trajectory established by the UCR Study.

Population projections for the District reflect these regionally refined UCR Study estimates and therefore align with those used by the other retailers participating in the 2025 RUWMP. This approach ensures that demand projections developed for participating parties are consistent with basin-wide planning assumptions and analyses. Detailed methodologies used to develop and refine the regional population projections included in the UCR Study are presented in Sub-Chapter 2.1.6 Current and Projected Population of Regional Chapter 2 – The Mojave Region.

Historical population trends within the District have generally followed broader regional growth patterns associated with residential development, employment opportunities, and land availability in the High Desert. Much of the growth over the past several decades has been characterized by low-density suburban neighborhoods and expansion of retail and commercial areas to serve the needs of a growing population. Continued growth is anticipated over the planning horizon, which will influence future water demand, infrastructure requirements, and resource management strategies. The population estimates presented in this sub-chapter provide the basis for the demand projections discussed in subsequent sub-chapters.

Table 11-3 presents the District’s historical population while Table 11-4 presents the District’s population growth over the last decade. The population values reflect the Hesperia Water District service area, which generally corresponds to the City of Hesperia’s boundaries as shown in Figure 11-1, but extends beyond the City limits in some areas and excludes small portions of the City in the Oak Hills Community Plan Area.

T
ABLE 11-3: HISTORICAL POPULATION

TABLE 11-4: POPULATION GROWTH RATE - 2015-2024

11.3.2 Projected Population
CWC Section 10631(a) requires urban retail water suppliers to evaluate projected service area populations while considering past growth rates, economic conditions, and anticipated land use changes. Coordination with local land use planning efforts helps ensure that anticipated development patterns are appropriately represented in long-term demand forecasting.

Population within the District is projected to increase steadily over the planning horizon, reflecting continued residential development, housing availability, and the community’s role as a regional population center in the High Desert. Growth is expected to occur primarily through suburban expansion supported by commercial and service development needed to accommodate new residents. While growth rates are projected to moderate over time, overall population is expected to continue increasing throughout the planning horizon. More 1990 2000 2010 2015 2020 2025
50,976 62,592 89,742 92,022 99,328 120,530
2015 2016 2017 2018 2019 2020 2021 2022 2023 2024
Population 92,022 92,732 93,787 94,676 95,905 99,328 103,568 107,809 112,049 116,290 Growth Rate 0.77% 1.14% 0.95% 1.30% 3.57% 4.27% 4.09% 3.93% 3.78%

broadly, incorporated areas served by municipal water providers within the RUWMP Planning Area are projected to accommodate a substantial share of future regional population growth relative to unincorporated areas as illustrated in Sub-Chapter 2.1.6 Current and Projected Population of Regional Chapter 2 – The Mojave Region.

Table 11-5 presents the District’s projected population and associated growth rates through 2060.

T
ABLE 11-5: POPULATION FORECAST AND GROWTH RATE

11.3.3 Current and Projected Land Use
Land use patterns within the District’s service area are governed primarily by the City of Hesperia General Plan, which establishes the distribution, type, and intensity of development across residential, commercial, industrial, public, and open space uses. The City adopted a comprehensive update to its General Plan in July 2025, replacing the prior 2010 plan and providing updated land use designations, policies, and growth assumptions to guide long- term development.
50 The District’s service area, which is largely governed by the City of Hesperia’s land use framework, is characterized predominantly by low-density residential development interspersed with commercial corridors, industrial areas, public facilities, and open space.

Residential land uses represent the largest share of developed land and account for the majority of potable water demand, as discussed further in Sub-Chapter 11.5 Water Use Characterization.

Two adopted Specific Plans within the District’s service area are expected to influence future development patterns and associated water demand. These include the Main Street and Freeway Corridor Specific Plan and the Silverwood Specific Plan (formerly Tapestry Specific Plan). Specific Plans establish detailed land use regulations, phasing schedules, and infrastructure requirements for large development areas and collectively represent a 50 City of Hesperia General Plan 2025 accessed at: https://www.hesperiaca.gov/409/Hesperia-General- Plan
2025 2030 2035 2040 2045 2050 2055 2060
Hesperia Water
District 120,530 124,771 129,012 133,252 137,493 141,733 145,974 150,214 Growth Rate 3.52% 3.40% 3.29% 3.18% 3.08% 2.99% 2.90%

substantial portion of the City’s and District’s planned growth. In particular, the Silverwood Specific Plan encompasses thousands of acres and proposes a mix of residential uses, commercial areas, schools, parks, and open space developed over multiple phases spanning several decades. In addition to new development areas, continued infill development within existing neighborhoods is expected to contribute to future population growth. The General Plan notes that much of the existing housing stock consists of single-family detached homes on relatively large lots, with ongoing subdivision activity introducing a range of densities to accommodate diverse housing needs.

Land use planning decisions, including allowable densities, development intensity, and timing of Specific Plan buildout, will directly influence water demand, infrastructure requirements, and system operations within the District. The population projections presented in the prior subsection reflect these planned development patterns and provide the basis for estimating future water use across the service area.

Table 11-6 summarizes the adopted Specific Plans within the District’s service area, while Figure 11-2 illustrates their geographic distribution. Together, these areas identify the primary locations of anticipated residential, commercial, and mixed-use development that will influence future water demand and infrastructure needs.

T
ABLE 11-6: KNOWN LAND USE PLANS IN SERVICE AREA

51 The Main Street / Freeway Corridor Specific Plan establishes land use designations and development standards but does not identify a fixed number of residential dwelling units.

Existing or Planned Project Project Area (acres) Residential Units Main Street / Freeway Corridor Specific Plan 10,637 N/A51 Silverwood Specific Plan 9,336 16,196

FIGURE 11-2: KNOWN LAND USE PLANS IN SERVICE AREA MAP

11.3.4 Economic Trends & Other Social and Demographic
Factors
The District’s service area encompasses a community experiencing continued economic transition and growth. The City of Hesperia promotes itself as “Strategically Located, Rapidly Growing, Open for Business,” reflecting its role as a major residential, transportation, logistics, and service-oriented center within the High Desert portion of the Inland Empire. Historically, economic growth in the area has been driven by housing affordability and suburban expansion, attracting households seeking lower-cost alternatives to coastal and metropolitan markets. These conditions continue to support population growth within the District.

In recent years, the transportation and logistics sector has emerged as a primary driver of economic development. The service area’s proximity to Interstate 15 provides regional connectivity to Southern California markets and supports distribution, warehousing, and related commercial activity. Notable developments include the Hesperia Commerce Center, which hosts major tenants such as Maersk and Modway Furniture, as well as a planned large- scale Amazon fulfillment facility. Industrial expansion is further supported by infrastructure improvements, including rail connections that enhance freight movement capabilities. These developments are expected to increase local employment opportunities and contribute to sustained economic growth within the service area.

Despite growing local employment opportunities, the community has historically functioned as a net exporter of labor, with many residents commuting to employment centers elsewhere in the Inland Empire and Southern California. Future economic development efforts are focused on expanding local job opportunities to reduce commute patterns and strengthen the local employment base. Broader regional economic conditions that influence growth within the District are discussed in Sub-Chapter 2.1.7.2 Economic Trends and Other Social and Demographic Factors of Regional Chapter 2 – The Mojave Region.

Demographically, the service area is characterized by a growing and diverse population. The community includes a substantial Hispanic/Latino population and a mix of household types, income levels, and housing tenure. According to the 2020 Census, approximately 62.7 percent of residents identify as Hispanic or Latino, 26.8 percent as White, 5.8 percent as African American, and 1.6 percent as Asian, with 20.2 percent identifying as two or more races. The median household income is approximately $72,160, and roughly two-thirds of residents are homeowners. Approximately 16.9 percent of the population falls below the federal poverty line.

Sub-Chapter 11.4 – Water Supply and
Infrastructure Characterization
The District sources its water supplies primarily from groundwater. Through a municipal network of 15 active wells, the District pumps groundwater from the underlying Alto Subarea of the Mojave Basin Area (MBA). As discussed in Regional Chapter 3 – Regional Water Supply Characterization, the MBA is an adjudicated basin administered by a court-appointed Watermaster. The aforementioned regional chapter describes the MBA’s water supplies and related management structures and details. Generally, the District pumps groundwater that is recharged and managed by MWA, while obtaining supplemental water supplies through recycled water obtained from capturing and locally treating some of the originally pumped groundwater.

11.4.1 Groundwater
Groundwater is the primary water supply source for all urban retail water suppliers within the MBA. Hesperia Water District, like many of the MWA’s other retail agencies, pumps groundwater from the adjudicated MBA, specifically the Alto Subarea. The basin is recharged through several means, including natural recharge from the Mojave River, lateral subsurface groundwater movement from the adjacent San Gabriel mountains, imported water from the State Water Project (managed by MWA), and other sources like irrigation runoff, return flows from septic systems and water delivery systems, and treated wastewater effluent. A detailed description of the MBA, Subareas, aquifer characteristics, adjudication, management areas, and other adjudicated basins is presented in Sub-Chapter 3.1.1 Mojave Region Water Supply Sources of Regional Chapter 3 – Regional Water Supply Characterization.

11.4.1.1 Hesperia Water District’s Free Production Allowance Under the Judgment governing the MBA, each producer is assigned a Free Production Allowance (FPA), representing the annual quantity of groundwater that may be extracted without replacement obligations. The District’s FPA is based on historical production coupled with evaluation of groundwater conditions, as administered by MWA in its role as the Watermaster.

The District’s FPA changes over time as the Watermaster assesses supply availability for all adjudicated purveyors against the long-term health and production safe yield of the MBA.

The District’s FPA has continued to be significantly reduced as a percentage of the Base

Annual Production (BAP) number. Hesperia’s FPA is tracked through two entries in the Watermaster’s annual report: “Hesperia Water District” and “Hesperia, City of.” Hesperia Water District’s BAP in water year 2025 was 14,664 acre-feet per year and the City of Hesperia’s BAP was 6,736 acre-feet per year. The combined BAP for these entities in water year 2025 was 21,400 acre-feet per year.

Importantly, the City of Hesperia’s BAP and the Hesperia Water District’s BAP are still separated in the Watermaster’s annual report. The supplies for both entities have been aggregated to simplify the analysis of the available assets. Thus, the current 50.4% FPA of these sources is 10,786 acre-feet. Table 11-7 presents the District’s FPA for the most recent five-year period pursuant to the MBA Judgment. Detailed discussion of the adjudication framework and administration of production allowances is provided in Regional Chapter 3 – Regional Water Supply Characterization.

T
ABLE 11-7: LAST FIVE YEARS OF HESPERIA WATER DISTRICT'S FPA SUPPLY (AFY)

The 50.4% FPA represents a reduction that aligns with the long-term Production Safe Yield considered by the Watermaster. Accordingly, the District’s projected FPA in a normal year, single dry year, and five consecutive dry years through 2030 is set at 50.4% as shown in Table 11-8.

Year Base Annual Production Percent FPA FPA Supply
2021 20,907 55% 11,499
2022 21,267 50% 10,634
2023 21,267 53.3% 11,335
2024 21,277 50.4% 10,724
2025 21,400 50.4% 10,786

TABLE 11-8: PROJECTED MOJAVE ADJUDICATION FPA FOR THE DISTRICT THROUGH 2030 (AFY)

Although the Production Safe Yield of the MBA appears to be stabilizing in the Alto Subarea, out of an abundance of caution the future FPA has been reduced to 50% to address long- term water supply planning options. Table 11-9 presents the District’s projected FPA in a normal year, single dry year, and five consecutive dry years from 2030 through 2050 at 50%.

TABLE 11-9: PROJECTED MOJAVE ADJUDICATION FPA FOR THE DISTRICT THROUGH 2050 (AFY)

A summary of long-term reliability and other factors that will affect FPA such as hydrological and regulatory issues is provided in Regional Chapter 3 – Regional Water Supply Characterization.

Year Type Projected FPA
Normal 10,786
Single Dry Year 10,786
Multi-Year Drought 2026 (1st Year) 10,786
2027 (2nd Year) 10,786
2028 (3rd Year) 10,786
2029 (4th Year) 10,786
2030 (5th Year) 10,786
Projected FPA 2030 2035 2040 2045 2050
Normal 10,700 10,700 10,700 10,700 10,700
Single Dry Year 10,700 10,700 10,700 10,700 10,700
Multi-Year Drought Year 1 10,700 10,700 10,700 10,700 10,700 Year 2 10,700 10,700 10,700 10,700 10,700
Year 3 10,700 10,700 10,700 10,700 10,700
Year 4 10,700 10,700 10,700 10,700 10,700
Year 5 10,700 10,700 10,700 10,700 10,700

11.4.1.2 Carryover Water Supplies
The District does hold some carryover supplies as part of its overall water supply management in the Alto Subarea. Specifically, the District’s carryover supply totals 3,395 acre-feet.
52 Although these supplies may be available to meet the District's water needs, we do not account for these supplies in the availability analysis in this sub-chapter in order to preserve these supplies for purposes of meeting emergency supply conditions.

11.4.1.3 Replacement and Make-up Water Supplies
The District has taken actions to augment its water supplies through the Watermaster’s water replacement water supply program and by acquiring make-up water supplies. Replacement water supplies are those supplies acquired by the Watermaster in order to replace supplies pumped from the Basin that exceed the District’s annual FPA from the Alto Subarea. Make-up water supplies, by contrast, are acquired to satisfy obligations under the Judgment to maintain flows from the Alto Subarea to downstream subareas when natural conditions and production patterns would otherwise result in a shortfall.

A detailed description of these programs, obligations, and administrative processes is provided in Regional Chapter 3 – Regional Water Supply Characterization. Table 11-10 summarizes the quantities of replacement and make-up water supplied to the District during the most recent five-year period.

T
ABLE 11-10: LAST FIVE YEARS OF REPLACEMENT AND MAKE-UP WATER SUPPLIES (AFY)

52 Water Year 2025 Watermaster Report, Appendix H.
53 Water Acquisitions calculated as (Verified Production – Base FPA) + Makeup Water Obligation Year Water Acquisitions53
2021 6,697
2022 5,762
2023 5,001
2024 6,357
2025 6,950

11.4.2 Groundwater Quality
Groundwater produced by the District is obtained from wells completed in the Mojave River Groundwater Basin and is treated as necessary to meet all applicable federal and state drinking water standards prior to delivery to customers. Water quality within the basin is influenced by natural hydrogeologic conditions as well as localized land use and recharge patterns. The District routinely monitors groundwater quality in accordance with regulatory requirements to ensure the continued safety and reliability of its potable water supply.

Detailed information regarding the quality of water delivered to customers, including detected constituents, regulatory compliance status, and treatment practices, is provided annually in the District’s Consumer Confidence Report (CCR). The most recent available report is the 2024 CCR, published in June 2025, which reflects water quality data from the 2024 calendar year in accordance with state reporting requirements that mandate annual preparation and distribution of CCRs by July 1 of the following year. The CCR summarizes monitoring results for the most recent reporting year and demonstrates compliance with primary drinking water standards established by the U.S. Environmental Protection Agency and the State Water Resources Control Board Division of Drinking Water (SWRCB). The District’s most recent CCR is available through the District’s website and provides the most current information on potable water quality conditions. 54 While this section focuses on groundwater quality as it pertains to the District’s supply sources, a broader discussion of water quality conditions throughout the Mojave Region, including basin-wide characteristics, regulatory considerations, and regional management issues, is presented in Sub-Chapter 3.1.2 of Regional Chapter 3 – Regional Water Supply Characterization.

Table 11-11 presents a summary of groundwater quality constituents based on information reported in the District’s 2024 CCR. The table reflects a subset of reported constituents and has been adapted for clarity and relevance to this UWMP. 54 Hesperia Water District 2024 CCR available at:
https://www.hesperiaca.gov/DocumentCenter/View/20046/2024-Annual-Water-Quality-Report

TABLE 11-11: HESPERIA WATER DISTRICT POTABLE WATER QUALITY Water Quality Standards Goal Level Max Level Range Amount Detected
Primary Standards
Arsenic (ppb) 0.004 10 ND - 2.4 0.29
Chromium (ppb) 100 50 ND - 1.4 0.09
Fluoride (ppm) 1 2 ND - .66 0.21
Goss Alpha Particle Activity (pCi/L) 0 15 ND - 4.88 1.4 Nitrate as N (ppm) 10 10 ND - 2.7 0.9
Total Coliform Bacteria (# of positive samples) 0 <5% N/A 0 Fecal Coliform or E.coli (# of positive samples) 0 0 N/A 0 Chlorine (ppm) 4 4 0.2 - 1.40 0.7
Copper (ppm) 0.3 1.3 N/A ND
Lead (ppb) 0.2 15 N/A ND
Secondary Standards
Chloride (ppm) N/A 500 3.3 - 31 12.63
Foaming Agents (ppm) N/A 500 ND - 0.27 0.02
Odor (tons) N/A 3 ND - 1 0.93
Specific Conductance (umho/cm) N/A 1,600 110 - 360 243.33 Sulfate (ppm) N/A 500 1.9 - 23 10.47
Turbidity (NTU) N/A 5 ND - 0.2 0.02
TDS (ppm) N/A 1,000 73 - 240 151.53
Federal Unregulated Contaminates
Alkalinity, Bicarbonate (ppm) N/A N/A 83 - 140 101.6
Calcium (ppm) N/A N/A 14 - 47 24.73
Chromium, Hex (ppb) N/A N/A ND - 10 2.68
Hardness (ppm) N/A N/A 26 - 140 75
Magnesium (ppm) N/A N/A ND - 6.9 3.35
Perfluorohexanoic Acid (PFHXA) N/A N/A ND - 3.2 3.2
Perfluoropentanoic Acid (PFPEA) N/A N/A ND - 2.4 2.4
pH (units) N/A N/A 7.1 - 8.2 7.71
Sodium (ppm) N/A N/A 15 - 29 21.2

11.4.3 Recycled Water Supplies
The Victor Valley Wastewater Reclamation Authority (VVWRA) is a Joint Powers Authority that provides regional wastewater treatment and recycled water services to its member agencies, including the Town of Apple Valley, the cities of Hesperia and Victorville, and San Bernardino County Service Areas 42 and 64. This section summarizes existing and projected wastewater flows within the District’s service area and identifies current and planned opportunities for use of recycled water.

A portion of wastewater generated within the District is conveyed through the City of Hesperia’s sewer collection system to VVWRA facilities for treatment, while the remaining areas continue to rely on on-site wastewater disposal systems (septic systems). Expansion of the sewer collection system over time is expected to increase the volume of wastewater available for centralized treatment and future recycled water production. Coordination among the City, the District, and VVWRA is necessary to ensure that wastewater infrastructure planning aligns with anticipated growth and supports long-term recycled water supply development. VVWRA’s regional strategy for managing wastewater flows and sustaining local water supplies includes development of subregional water reclamation plants (WRPs) located within member agency service areas. These facilities function as “scalping plants,” meaning they treat a portion of the local wastewater flow to produce recycled water for nearby uses while returning solids to the regional collection system for final treatment at VVWRA’s main plant. This approach reduces conveyance demands, lowers energy requirements associated with pumping treated water long distances, and provides locally available recycled water supplies to support community needs.

In Hesperia, a WRP located near Maple Avenue began delivering recycled water in the Spring of 2022. The facility has an initial treatment capacity of approximately 1.0 million gallons per day and produces recycled water that is conveyed to storage facilities and distribution infrastructure for non-potable uses. Current primary uses include irrigation of the Hesperia Course and nearby parks and landscaped areas. Additional recycled water use is anticipated as large planned developments are constructed. The Silverwood Specific Plan Development (formerly Tapestry Specific Plan Development) is currently under development and is expected to incorporate recycled water to meet a substantial portion of the project’s non- potable demands. According to the project’s Water Supply Assessment, approximately 40% of the project’s water demands could ultimately be supplied with recycled water once the necessary treatment and distribution infrastructure is implemented. These efforts represent a significant step toward implementing the City’s Recycled Water Master Plan and expanding recycled water use within the service area. Recycled water supplies will continue to play an important role in conserving potable groundwater resources and enhancing long-term water supply reliability for the District and the broader region. Table 11-12 summarizes the quantities of recycled water utilized by the District during the most recent five-year period.

TABLE 11-12: LAST FIVE YEARS OF RECYCLED WATER SUPPLIES (AFY)

The approach to forecasting future recycled water supplies is informed by the City of Hesperia’s 2015 Recycled Water Master Plan (RWMP), which identified potential recycled water customers and estimated long-term demand associated with expanded wastewater treatment and distribution infrastructure. Consistent with the methodology used in the District’s 2020 UWMP, recycled water supply projections are intentionally conservative relative to the long-term supply and demand estimates identified in this chapter. This approach provides a planning baseline that reflects currently available infrastructure and near-term implementation timelines while recognizing that actual recycled water deliveries could increase as additional recycled water facilities and distribution systems are developed.

Table 11-13 shows the projected recycled water in 2026-2030 in normal, single dry, and five consecutive dry years while Table 11-14 shows the projected recycled water supplies from 2030-2050 in normal, single dry, and five consecutive dry years.

T
ABLE 11-13: PROJECTED RECYCLED WATER SUPPLIES 2030 (AFY) 55 Recycled water deliveries began in Spring 2022.

Year Recycled Water Supplies
2021 055
2022 169
2023 311
2024 389
2025 240
Year Type Projected Recycled Water Supplies
Normal 500
Single Dry Year 500
Multi-Year Drought 2026 (1st Year) 500
2027 (2nd Year) 625
2028 (3rd Year) 750
2029 (4th Year) 875
2030 (5th Year) 1,000

TABLE 11-14: PROJECTED RECYCLED WATER SUPPLIES THROUGH 2050 (AFY)

11.4.4 Desalination Opportunities
The UWMPA requires urban water suppliers to evaluate potential opportunities for the use of desalinated water CWC Section 10631[i]. Based on current conditions, desalination is not considered a viable supply option for the District due to the absence of suitable source waters and the substantial cost associated with treatment, conveyance, and disposal.

Therefore, the District has no plans to develop desalination facilities, and desalinated supplies are not incorporated into the supply projections presented in this sub-chapter.

11.4.5 Water Transfers and Exchanges
In addition to its groundwater resources and planned alternative supplies, such as recycled water, the District continues to evaluate opportunities to acquire water supplies from other agencies and sources. Transfers, exchanges, and groundwater banking programs represent important mechanisms for enhancing the long-term reliability and flexibility of the District’s available supplies.

The District has executed numerous permanent transfers of BAP rights from other parties within the Alto subarea to increase its long-term groundwater production capacity under the MBA Judgment. These permanent transfers augment the District’s BAP and therefore increase the quantity of groundwater that may be produced annually without incurring replacement obligations. The District continues to pursue such opportunities as they become available and anticipates further augmenting its BAP over time.

In addition, the District regularly participates in temporary transfers of FPA to supplement its baseline production in a given year. These temporary transfers may occur through direct transactions with other producers or may result from replacement and makeup water Projected Recycled Water Supplies 2030 2035 2040 2045 2050 Normal 1,000 1,500 2,000 2,500 3,000
Single Dry Year 1,000 1,500 2,000 2,500 3,000
Multi-Year Drought Year 1 1,000 1,500 2,000 2,500 3,000 Year 2 1,000 1,500 2,000 2,500 3,000
Year 3 1,000 1,500 2,000 2,500 3,000
Year 4 1,000 1,500 2,000 2,500 3,000
Year 5 1,000 1,500 2,000 2,500 3,000

obligations administered by the Watermaster, including transactions involving other subareas. Supplies obtained through temporary transfers are incorporated into the District’s annual water supply portfolio as needed to meet demands.

The District expects to continue utilizing transfer and exchange mechanisms, when available, as part of its overall water management strategy to support both near-term operational needs and long-term supply reliability.

11.4.6 Supply Summary
Groundwater serves as the District’s principal water supply source. These supplies, pumped from the Alto Subarea of the MBA, are generally sufficient to meet existing and future demands. To enhance sustainability and reduce potable demand, the District also produces limited recycled water for irrigation at places like the Hesperia Golf Course. Additionally, the District is involved in regional initiatives with MWA exploring supplemental supplies, such as the One Water Project, which could feasibly deliver stored water from outside basins to support future growth.

The District’s water supplies are aggregated into the historical managed groundwater system. Managed groundwater consists of supplies provided through the Mojave Basin Area Adjudication, including make-up and replacement supplies as well as transfers and exchanges among producers. Under the MBA Judgment, producers in the Alto Subarea are able to meet their water supply requirements through production from the basin’s managed groundwater system. This system incorporates the natural yield of the basin along with supplies made available through regional management actions, including imported water recharge managed by MWA, conservation, water reuse, and transfers of FPA among producers. Consistent with this framework, the District’s total managed groundwater production for the historical period represents the supply available to meet system demands.

Total managed groundwater production from 2021 through 2025 is shown in Table 11-15.

T
ABLE 11-15: DISTRICT'S MANAGED GROUNDWATER PRODUCTION 2021-2025 (AFY)

Year Groundwater Production
2021 14,253
2022 13,645
2023 12,604
2024 13,724
2025 13,852

Projected groundwater supplies are derived from the demand projections described in Sub- Chapter 11.5 Water Use Characterization. Within the adjudicated MBA management framework, the District’s groundwater production adjusts to meet water demands through the managed groundwater system. Accordingly, projected groundwater supplies for the planning horizon are shown in Table 11-16 and Table 11-17. 56 TABLE 11-16: DISTRICT'S PROJECTED MANAGED GROUNDWATER SUPPLY 2026-2030 (AFY)

TABLE 11-17: DISTRICT'S PROJECTED MANAGED GROUNDWATER SUPPLY THROUGH 2050 (AFY)

56 The values presented in Tables 11-16 and 11-17 have been rounded to reflect congruency with the projected demands presented in Sub-Chapter 11.5 Water Use Characterization.

Year Type Managed Groundwater Production
Normal 14,180
Single Dry Year 14,180
Multi-Year Drought 2026 (1st Year) 14,180
2027 (2nd Year) 14,250
2028 (3rd Year) 14,320
2029 (4th Year) 14,390
2030 (5th Year) 14,435
Managed Groundwater Production 2030 2035 2040 2045 2050 Normal 14,345 14,765 15,090 15,145 15,740
Single Dry Year 14,345 14,765 15,090 15,145 15,740
Multi-Year Drought Year 1 14,345 14,765 15,090 15,145 15,740 Year 2 14,500 14,830 15,155 15,480 15,805
Year 3 14,565 14,895 15,220 15,545 15,870
Year 4 14,635 14,960 15,285 15,610 15,935
Year 5 14,700 15,025 15,350 15,675 16,000

11.4.7 Delivery System Details
The District’s potable water system conveys groundwater produced from wells located throughout the service area to storage and distribution facilities that deliver water to customers. Extracted groundwater is conveyed to one of the District’s storage reservoirs, which collectively provide approximately 64.5 million gallons of storage before being distributed through the pressurized potable water system. The distribution system consists of more than 600 miles of pipeline, approximately 5,000 fire hydrants, and approximately 29,205 service connections. In recent years, the District has expanded the use of Advanced Meter Infrastructure (AMI), with approximately 81% of meters converted, improving the ability to monitor system performance and customer water use. The District’s potable water distribution system is shown in Figure 11-3.

F
IGURE 11-3: POTABLE WATER SYSTEM

Sub-Chapter 11.5 – Water Use
Characterization
Understanding water use characteristics is essential for the District to reliably and cost- effectively manage its water supplies and meet the needs of customers within its service area. This sub-chapter characterizes the District’s retail customer water needs – current and forecast over the next few decades. Characteristics regarding how water use varies amongst different land use classifications, throughout the year, and under differing hydrologic conditions, help to bolster that understanding.

A thorough characterization and analysis provides a realistic prediction of future water use based upon the District’s past and current water use, in addition to considerations of anticipated growth, new regulations, climate change conditions and trends in customer water use behaviors. The analysis presented in this sub-chapter utilizes the water use forecast methodology presented in Sub-Chapter 4.1 of Regional Chapter 4 – Water Use Characterization which examines each water use sector for a variety of factors before aggregating the information into a comprehensive projection of customer water use that becomes the foundation for integration with the District’s water supplies, presented in Sub- Chapter 11.4 Water Supply and Infrastructure Characterization, to assess long-term water system reliability, presented in Sub-Chapter 11.7 Water System Reliability and Drought Risk Assessment.

As discussed in Regional Chapter 1 – Introduction, there have been no legislative changes to the UWMPA since the adoption of the District’s 2020 UWMP; however, updates to annual water use reporting have been implemented. These include Urban Water Use Objective (UWUO) reports, and monthly drought and conservation reporting to the Safe and Affordable Funding for Equity and Resilience (SAFER) portal that are consolidated annually into an auto- generated Clearinghouse Annual Inventory Report (CAIR).

This section is organized as follows:

Current Customer Water Use – This subsection presents actual water use data reflecting the District’s residential and non-residential customers for 2021 through 2025 as well as distribution system losses for this same period.

Compliance with Urban Water Use Objectives and past urban water use efficiency efforts – This subsection documents the derivation of the District’s UWUO, comparison to the

District’s actual water use, UWUO reporting process, and past urban water use efficiency efforts, including the District’s 2020 GPCD target.

Forecasting Customer Use – This subsection presents the derivation and results of future water use forecasts for potable and non-potable water within the District’s service area and estimation of distribution system losses. This subsection also estimates the variations in customer water use the District should expect during years with low rainfall as well as discusses longer-term climate change considerations.

Forecasting Water Use for DRA and Annual Assessment – This subsection focuses on the subset of the customer water use forecast that is necessary for completing the five- year Drought Risk Assessment (DRA) and defining the “unconstrained demand” for purposes of the District’s annual water supply and demand assessment.

Projecting Disadvantaged Community Water Use – This subsection presents the estimated water use necessary to meet lower income households, pursuant to CWC Section 10631.1.

11.5.1 Current Customer Water Use
As described in Sub-Chapter 11.2 Water Service and System Description, the District provides water service to approximately 29,205 service connections within its service area. Under normal operating conditions, customers are served groundwater supplies pumped from wells located throughout the District and treated to meet all applicable state and federal drinking water standards. Information regarding the District’s current customers, recent water use patterns, and expected trends in water demand provides the basis for developing the water use forecasts presented in this 2025 RUWMP. Furthermore, annual records of actual water use provides the basis for determining the District’s compliance with its UWUO, reported annually to DWR beginning in January of 2024.

11.5.1.1 Customer Water Use 2021 - 2025
Recent customer water use data assists the District in understanding water use trends, effects of any temporary use restrictions imposed during the most recent prolonged drought and recovery from such temporary restrictions, effects of long-term demand management measures, and other pertinent water use factors relevant to its forecast of future water use.

The District is also required to quantify past customer water use pursuant to CWC Section 10631(d)(1). The District records potable water use within five primary categories:

Single-Family Residential
Multi-Family Residential
Commercial and Institutional
Irrigation

Other
Table 11-18 presents the District’s past customer potable water use by customer classification for 2021 – 2025 in acre-feet.

TABLE 11-18: POTABLE CUSTOMER USE 2021-2025 (AF)

Use Category Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Total Single-Family
Residential
2021 740 508 602 545 909 745 1,242 1,000 1,226 922 909 594 9,942 2022 741 477 624 550 850 706 1,118 886 1,176 880 844 563 9,413 2023 679 433 571 440 703 685 1,050 853 1,117 783 846 613 8,774 2024 724 458 612 436 717 711 1,088 965 1,259 848 969 652 9,439 2025 745 523 637 485 815 717 1,058 950 1,222 820 940 579 9,491 Multi-Family
Residential
2021 92 67 71 65 97 79 119 108 115 108 93 69 1,084
2022 92 62 73 68 93 79 113 96 117 95 104 65 1,057
2023 93 59 77 54 84 77 111 91 120 92 96 72 1,026
2024 95 59 81 55 86 82 110 106 126 91 110 82 1,085
2025 95 72 85 67 95 78 111 102 124 93 104 69 1,096
Commercial/
Institutional
2021 86 41 77 39 102 50 112 64 110 64 92 43 881
2022 93 43 85 47 90 47 102 55 103 59 86 41 851
2023 84 41 72 44 76 45 97 51 100 56 83 49 800
2024 88 40 79 45 78 52 92 57 107 56 98 52 843
2025 90 45 80 40 87 47 96 61 104 61 103 46 860
Irrigation
2021 27 8 14 12 39 25 58 36 69 32 45 12 377
2022 21 7 18 14 37 36 62 40 73 63 45 30 446
2023 24 16 13 22 25 91 66 75 71 64 57 69 594
2024 36 13 18 23 33 77 61 82 84 73 64 39 602
2025 35 29 23 29 37 87 67 90 90 65 64 40 656
Other
2021 59 92 73 85 131 111 184 146 188 109 94 38 1,311
2022 39 26 54 59 99 143 257 104 182 122 95 35 1,214
2023 41 23 23 24 72 91 171 125 160 95 90 49 963
2024 44 17 35 25 78 112 170 138 180 102 100 68 1,068
2025 78 49 53 81 106 93 150 119 153 97 94 36 1,110
Total Metered
Deliveries
2021 1,003 717 838 746 1,279 1,009 1,716 1,355 1,708 1,234 1,234 755 13,595 2022 986 615 853 738 1,168 1,011 1,651 1,180 1,651 1,221 1,174 733 12,981 2023 921 573 756 584 961 989 1,496 1,195 1,568 1,089 1,172 852 12,156 2024 988 587 826 584 991 1,033 1,521 1,348 1,756 1,170 1,342 892 13,038 2025 1,043 717 877 703 1,141 1,023 1,482 1,323 1,694 1,136 1,304 771 13,213

The “Other” water use category included in Table 11-18 captures a range of small, non- standard uses related to fire and construction services. Additionally, the District supplies non- potable water for irrigation of parks, landscapes, and the Hesperia Golf Course. Table 11-19 provides the historic monthly deliveries of non-potable water.

TABLE 11-19: NON-POTABLE CUSTOMER USE 2021-2025 (AF)
Use Category Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Total Non-Potable
2021 6 0 4 0 15 0 26 0 26 0 15 0 94
2022 8 0 8 0 14 27 24 26 26 56 11 48 248
2023 4 12 2 16 9 66 23 44 25 36 16 53 307
2024 9 16 3 71 11 56 23 44 28 47 14 48 369
2025 6 66 4 49 11 56 20 32 25 0 0 0 268

The single-family residential classification continues to illustrate two important characteristics of the District’s water service: (1) it represents about 72% of the District’s annual potable water demand, and (2) it has summer demands that are roughly two times the monthly volume needed in winter months. When combined with multi-family residential use, overall residential use represents over 80% of the District’s potable water service. When compared to previous use data, these water use characteristics have remained relatively consistent throughout the last 10 years, reflecting the District’s predominantly residential service area and the continued prevalence of low-density single-family housing throughout Hesperia.

11.5.1.2 Existing Distribution System Losses
Distribution system water losses (also known as “real losses”) are the physical water losses from the District’s water distribution system up to the point of delivery to the customer’s system (e.g., up to the residential water meter).

Since 2016, the District has been required to quantify its distribution system losses using the American Water Works Association Method (AWWA).
57 An electronic copy of the audit in Excel
format is to be submitted to DWR by October 1 of each year for the prior year’s estimated system losses, using DWR’s online submittal tool pursuant to California Code of Regulations (CCR) Section 638.5. Although the AWWA-based audit remains in effect as the primary tool for monitoring distribution system losses, mandated water loss reductions are on the horizon with the SWRCB’s April 1, 2023 adoption of volumetric water loss performance standards.

Pursuant to CCR Section 996, the SWRCB will require suppliers to reduce real loss by January 1, 2028 to no greater than the real water loss standard calculated in its 2027 audit. After 2028, 57 Title 23 California Code of Regulations Section 638.1 et seq.

the District shall assess compliance every three years as an average of recent losses.

Additionally, the District will be required to evaluate apparent losses and submit an inventory of apparent losses should average losses exceed the real water loss standard.

Consistent with DWR’s 2025 UWMP guidance, distribution system losses are reported using values submitted through DWR’s Water Loss Audit Program. Table 11-20 summarizes the District’s reported losses for 2021 through 2024. 2025 data was not available at the time this 2025 RUWMP was prepared due to the reporting schedule associated with the AWWA water loss audit process.

T
ABLE 11-20: DISTRIBUTION SYSTEM LOSS 2021-2024

Due to the dynamic functions of a pressurized potable water distribution system, the estimated annual distribution system loss as a percentage of water entering the system will vary year to year and month to month. On average, however, the District’s distribution system loss represents about 6.6% of water entering the system.

11.5.1.3 Water Loss Control Standard
CWC Section 10608.34 required the SWRCB to develop water loss control and performance standards (Real Water Loss Standards) applicable to urban retail water suppliers. The Real Water Loss Standard for the District was developed using information submitted as part of the District’s annual water loss reporting to the State, specifically for the period 2017 through 2020. The resulting Real Water Loss Standard is 16.3 gallons per (active and inactive) service connection per day. The resulting Real Water Loss Standard as an average percent of total water supplied is 3.7%. Using the information from the same period, the average “apparent” water loss averaged 1.0% (of total water supplied). The total water loss estimate as a percentage of total water supplied is 4.6%, although recent AWWA audits discussed above show losses closer to 7%.

11.5.2 Compliance with Water Use Targets and
Objectives
This subsection examines the District’s derivation and compliance with state-mandated water use targets and objectives. The Water Conservation Act of 2009, also known as SB X7-7, introduced water conservation targets that served as a valuable measure of progress through 2020 and beyond.
2021 2022 2023 2024

4.2% 15.0% 3.0% 4.2%
Average: 6.6%

11.5.2.1 Compliance with 2020 Urban Water Use Target
SB X7-7, also known as the Water Conservation Act of 2009, introduced sustainable water use and demand reduction legislation requiring the District to make incremental progress in reducing per capita water use. Specifically, urban water retailers were tasked with achieving a 10% reduction in per capita water use by December 31, 2015, and a 20% reduction by December 31, 2020. Beyond 2020, although reporting on compliance is no longer required, this target remains valuable as a baseline for the District to measure progress on achieving water efficiency goals.

The District’s 2020 target was established in the 2015 UWMP as 184 GPCD, derived as the “gross water use” divided by the population during a defined baseline period, and reduced pursuant to one of four methods defined under CWC Section 10608.20(b). The District’s calculation of their 2020 actual GPCD used the same methodology: “Gross water” was defined as total water production measured and reported based upon well production records. This value, divided by the District’s estimated population in 2020, resulted in a compliance value of 129 GPCD. Because this value was less than the District’s established target, the District was determined to be in compliance with CWC Section 10608.24(b).

Although not required by the UWMPA, in 2025, the District was determined to have an actual GPCD of 105, calculated using the same methodology presented above.

11.5.2.2 Urban Water Use Objective Compliance
In 2018, the California Legislature passed Senate Bill 606 and Assembly Bill 1668, directing the SWRCB to adopt standards to encourage more efficient urban water use. This legislation, known as "Making Conservation a California Way of Life," was adopted in 2024, establishing individualized UWUO for each urban retail water supplier. In contrast to the SB X7-7 per capita targets, this legislation functions as a water budget tailored to a supplier’s service area, considering residential indoor use, residential and commercial outdoor use based on local evapotranspiration and irrigable landscape area, water loss, and bonus incentives for potable reuse. In addition to the volumetric UWUO, the regulation establishes performance measures for commercial, industrial, and institutional (CII) sectors. The standards become progressively more stringent through 2040. In each of the first three reporting years, the District submitted required annual reports to the SWRCB demonstrating that actual water use remained below its calculated UWUO, confirming compliance in 2023, 2024, and 2025.

11.5.3 Forecasting Customer Use
Future water use within the District’s service area is projected using a regionally consistent forecasting methodology developed as part of the 2025 RUWMP. As described in Sub- Chapter 4.1.2 Forecasting Regional Water Use of Regional Chapter 4 – Water Use Characterization, this methodology integrates population and land use projections, historical

water use trends, and demand management assumptions to estimate future water demands across participating agencies.

Consistent with this approach, the District’s future water use projections reflect both anticipated changes in customer demand and continued implementation of water use efficiency measures. Forecasts are developed by considering existing customer use characteristics, projected growth in population and service connections, and expected changes in per capita water use over the planning horizon.

The results of this regional forecasting framework, as applied to the District, are presented in the following subsections and corresponding tables.

11.5.3.1 Existing Customer Future Use
Future water use associated with the District’s existing customer base is projected based on current potable water use characteristics and representative GPCD values. As described in Subsection 11.5.2.1, the District’s current GPCD, derived from recent water production and population data, reflects the combined water use of all customer sectors, including both residential and non-residential demands.

The methodology used to develop the representative GPCD value for existing customers is fully described in Sub-Chapter 4.1.2 Forecasting Regional Water Use of Regional Chapter 4 – Water Use Characterization. In general, this approach utilizes total annual potable water production divided by the corresponding service area population to establish a baseline GPCD value representative of current conditions.

For purposes of projecting future demand associated with existing customers, the District has assumed that current water use levels will remain constant over the planning horizon. This assumption reflects observed demand conditions within the District’s service area, where water use has stabilized following prior conservation efforts, regulatory requirements, and long-term demand management measures. As such, existing customer demand is considered “hardened” and no additional reductions in per capita water use have been applied to this customer group.

Accordingly, the District’s existing customer demand is projected to remain at approximately 14,110 acre-feet per year, based on a representative GPCD of 105, for the duration of the planning horizon. Because the representative GPCD is derived from total potable water production, it inherently includes distribution system losses; therefore, no separate adjustment for the District’s representative loss percentage, as described in the prior subsection, has been applied to the existing customer demand projections.

11.5.3.2 New Customer Future Use
Future water use associated with new customers is projected using a regionally consistent forecasting methodology developed as part of the 2025 RUWMP as described in Sub-Chapter

4.1.2 Forecasting Regional Water Use of Regional Chapter 4 – Water Use Characterization.

This approach applies representative water use factors to projected population growth to estimate incremental demand associated with new development within the District’s service area.

Unlike existing customer demand, which is based on observed production, the new customer forecast is developed by aggregating the individual components of the District’s GPCD to reflect anticipated water use characteristics for future growth and development. These components distinguish between residential indoor and outdoor use, as well as non- residential demands, and are applied to projected population growth to estimate future demand.

For the District, the representative GPCD components applied to new customers are as follows:

Indoor Residential Use: 47 GPCD
Outdoor Residential Use: 3 GPCD
Total Non-Residential Use: 24 GPCD
Total Use: 74 GPCD
As with the existing customer demand GPCD, the resulting new GPCD represents total potable water production. However, the composition of this GPCD differs for new customers, as residential indoor water use is reduced over time to reflect compliance with applicable UWUO indoor standards, while outdoor residential and non-residential (CII) components are assumed to remain constant. The specific implementation schedule and applicable indoor water use standards are described in Sub-Chapter 4.1.2 Forecasting Regional Water Use of Regional Chapter 4 – Water Use Characterization. Accordingly, the aggregate GPCD applied to new customers declines over the planning horizon as indoor efficiency requirements are incrementally achieved. Because the representative GPCD is based on total potable water production, it inherently includes distribution system losses; therefore, no separate adjustment for the District’s representative loss percentage has been applied to new customer demand projections.

Table 11-21 presents the resulting combined existing and future customer water use forecast, with values rounded to the nearest five acre-feet, which serves as the basis for evaluating the District's ability to meet projected demands under normal and drought conditions as described in Sub-Chapter 11.7 Water System Reliability and Drought Risk Assessment.

T
ABLE 11-21: FORECAST FUTURE WATER USE (AFY)

2025 2030 2035 2040 2045 2050
14,110 14,435 14,765 15,090 15,415 15,740

11.5.3.3 Adjusting Water Use Forecasts for Single Dry and Multiple Dry Conditions
The water use forecast presented in Table 11-21 represents expected water needs under normal climatic conditions. In some regions, adjustments to this forecast may be warranted under drier conditions to reflect increased irrigation resulting from reduced rainfall. However, within the High Desert climate of the RUWMP Planning Area, urban water use is not typically influenced by variations in rainfall. Landscape and agricultural irrigation demands are not dependent on precipitation to meet water needs; therefore, reduced rainfall does not result in increased water use as it might in more temperate or rainfall-dependent regions.

Accordingly, no adjustments have been made to the forecast to account for single dry or multiple dry year conditions. The values presented in Table 11-21 represent unconstrained demand and are assumed to be consistent across all hydrologic year types. 58 11.5.3.4 Climate Change Considerations
Incorporating climate change considerations into water use analysis can help inform long- term planning by identifying potential shifts in demand patterns, such as increased landscape irrigation associated with hotter and drier conditions. However, within the High Desert climate of the RUMWP Planning Area, baseline conditions are already characterized by low precipitation and high evapotranspiration rates. As a result, near-term climate change is not expected to materially alter water use behavior or increase demand beyond levels already reflected in existing conditions. Accordingly, no adjustments have been made to the water use forecast to account for climate change. While long-term climate change may incrementally increase evapotranspiration, such effects are expected to be nominal relative to current conditions. The District will continue to evaluate potential climate-related impacts in future UWMP updates and through ongoing regional water planning efforts.

11.5.4 Forecasting Water Use for DRA and Annual
Assessment
This subsection presents the subset of the District’s customer water use forecast that is used to evaluate short-term water supply reliability under drought and operational planning conditions. Specifically, this subsection supports two related but distinct analyses required 58 California Water Code Section 10632(a)(2) states water suppliers should use “unconstrained demand” when performing their annual water supply and demand assessment. This reflects the expected demand prior to implementing shortage response actions as detailed in a Water Shortage Contingency Plan.

under California Water Code: the five-year Drought Risk Assessment (DRA) and the Annual Water Supply and Demand Assessment (Annual Assessment).

The DRA evaluates projected water demand over a five-year planning horizon under a sequence of dry conditions to assess potential supply shortfalls. The Annual Assessment, by contrast, is conducted each year and evaluates water supply and demand conditions over a rolling twelve-month period spanning July through June, incorporating both current year conditions and near-term projections. Together, these analyses rely on a consistent representation of “unconstrained demand” derived from the District’s long-term water use forecast presented in the preceding subsections. The following subsections describe the methodology and results used to develop water demand projections for each of these planning efforts.

11.5.4.1 Projecting Water Use for Five-year Drought Risk Assessment
The DRA requires the District to evaluate water supply reliability over a five-year planning horizon under a sequence of dry conditions. Consistent with CWC Section 10635 and guidance provided in the 2025 UWMP Guidebook, this assessment is based on a projection of “unconstrained demand” representing anticipated customer water use absent shortage response actions.

For the purposes of the DRA, the District’s projected water demands are derived directly from the long-term water use forecast described in the preceding subsections. This forecast incorporates projected changes in population, service connections, and per capita water use, as well as the effects of ongoing water use efficiency measures and regulatory requirements.

Because the DRA is intended to evaluate baseline system reliability, no additional demand reductions associated with the District’s Water Shortage Contingency Plan (WSCP) are applied.

Projected demands for the DRA are derived from the District's long-term water use forecast developed for the 2025 RUWMP and the District’s retail-specific chapter and are expressed on an annual basis for each of the five-years within the planning horizon. No additional adjustments are applied; the annual values reflect the same underlying methodology and assumptions used to develop the five-year planning increment forecasts presented elsewhere in this sub-chapter. These demand projections reflect total potable water demand, including residential, commercial, institutional, and other customer uses, as well as distribution losses. The demand projections used for the DRA are consistent with those used in the Annual Assessment to ensure alignment in the District’s evaluation of water supply reliability across planning timeframes.

Table 11-22 presents the District’s projected unconstrained water demands for the DRA period (2026-2030), with values rounded to the nearest five acre-feet. These values form the basis

for the reliability analysis presented in Sub-Chapter 11.7 Water System Reliability and Drought Risk Assessment.

TABLE 11-22: FORECAST DRA WATER USE FOR 2026 THROUGH 2030 (AFY)

11.5.4.2 Projecting Water Use for Annual Assessments
The District conducts an Annual Water Supply and Demand Assessment each year in accordance with CWC requirements. These assessments are prepared and submitted to DWR by July 1 and evaluate anticipated water supply and demand conditions over a rolling twelve-month period spanning July through June.

The District has completed and submitted an Annual Assessment each year since 2022, as required by statute. While the results of these assessments are not included in this UWMP, the methodology and demand assumptions applied are consistent with those presented in this sub-chapter.

11.5.5 Projecting Disadvantaged Community Water Use
Pursuant to CWC Section 10631.1, urban retail water suppliers are required to include projected water use for lower income households in their UWMPs. Per California Health and Safety Code Section 50079.5, a lower income household is defined as one with an income below 80 percent of the area median income, adjusted for family size. For the purposes of the District’s sub-chapter within the 2025 RUWMP, the District’s service area is recognized as a Disadvantaged Community, and median income assumptions are consistent with those presented in Sub-Chapter 2.1.7.2 Economic Trends and Other Social and Demographic Factors of Regional Chapter 2 – The Mojave Region.
59 Accordingly, the water use forecast
presented in Table 11-21 is inclusive of disadvantaged community water use.

59 California Department of Water Resources, Disadvantaged Communities Mapping Tool, available at:
https://gis.water.ca.gov/app/dacs/
2026 2027 2028 2029 2030
14,180 14,250 14,320 14,390 14,435

Sub-Chapter 11.6 – Water
Conservation and Shortage
Response
Pursuant to CWC Sections 10631(e) and 10632, this sub-chapter summarizes the District's demand management measures and water shortage response framework. These efforts support efficient use of available water supplies and provide the foundation for managing water use under both normal and shortage conditions.

The District has historically implemented a range of demand management measures aimed at improving water use efficiency, reducing long-term demand, and supporting compliance with applicable State requirements. These measures include ongoing programs, policies, and regional coordination efforts designed to manage existing customer use and guide future water use patterns.

This sub-chapter also highlights key components of the District’s Water Shortage Contingency Plan (WSCP), including shortage levels, response actions, monitoring procedures, and communication strategies. The WSCP establishes the framework through which the District evaluates water supply conditions and implements staged response actions during periods of constrained supply. No substantive changes have been made to the District’s 2020 WSCP, and the shortage levels, response actions, monitoring procedures, and communication protocols described therein remain applicable; however, water supply reliability information has been updated and is presented in the 2025 RUWMP and this chapter, reflecting current data, assumptions, and planning conditions.

A complete description of the District’s WSCP, including detailed implementation procedures and supporting documentation, is provided in Appendix 11a.

11.6.1 Demand Management Measures
The District has implemented a comprehensive set of demand management measures (DMMs) to promote the efficient use of water and support long-term water supply reliability.

These measures are consistent with the requirements of CWC Section 10631(e) and are designed to reduce water use, improve system efficiency, and support compliance with State water use objectives.

The District is a member of the Alliance for Water Awareness and Conservation (AWAC), a regional partnership of water agencies within the Mojave Water Agency service area focused on promoting water conservation, public outreach, and coordination of demand management efforts. Through its participation in AWAC and collaboration with regional partners, the District leverages shared resources and consistent messaging to enhance the effectiveness of its conservation programs.

The District will continue to implement and refine its DMMs to support efficient water use and meet applicable regulatory requirements. Additional information regarding recent and planned demand management activities is provided in the following subsections.

11.6.2 Foundational Demand Management Measures
The District’s foundational DMMs remain unchanged from the 2020 UWMP and continue to serve as the basis for ongoing water conservation efforts. These measures include water waste prevention ordinances, metering, conservation-based rate structures, public education and outreach, programs to assess and manage distribution system losses, and coordination of conservation program implementation.

Water Waste Prevention Ordinances
The District has adopted and enforces water waste prevention ordinances that prohibit inefficient water use practices, such as excessive runoff, irrigation during inappropriate times, and other avoidable losses. These ordinances provide the regulatory framework for reducing unnecessary water use and are enforced through routine monitoring and customer outreach.

Metering
All potable water connections within the District are metered, allowing for accurate measurement of customer water use. Metering supports volumetric billing, enables customers to better understand their water use, and provides the data necessary for effective system management and demand forecasting.

Conservation Pricing
The District utilizes a conservation-oriented rate structure designed to encourage efficient water use. Water rates are structured to promote conservation by providing price signals that reflect increasing levels of water use and the cost of supplying water.

Public Education and Outreach
The District implements public education and outreach programs to inform customers about water conservation practices, available programs, and regulatory requirements. These efforts include coordination with regional partners to promote consistent conservation messaging and increase public awareness of water use efficiency.

Programs to Assess and Manage Distribution System Losses The District conducts ongoing efforts to assess and manage distribution system losses, including leak detection, system maintenance, and infrastructure improvements. These programs support efficient system operations and help minimize real water losses within the distribution system.

Conservation Program Coordination and Staffing Support
The District supports the implementation of DMMs through dedicated staffing and coordination with regional patterns. Participation in regional programs, including collaboration through the AWAC, enhances program effectiveness and allows the District to leverage shared resources and expertise.

11.6.2.1 Recent DMM Activities
The District has continued to implement and expand DMMs to improve water use efficiency and reduce system losses. Recent activities have focused on enhancing leak detection capabilities, improving customer engagement, and leveraging advanced technologies to better manage water use.

Satellite and Acoustic Leak Detection
In 2025, the District partnered with ASTERRA to perform satellite-based and acoustic leak detection across its service area. This effort identified a total of 149 leaks, including 92 leaks on the utility side of the meter, which contribute directly to non-revenue water losses. The program identified approximately 0.93 million gallons per day or 338.5 million gallons per year of potential recoverable water supply. This approach enabled the District to efficiently target areas of potential leakage using satellite-derived points of interest, reducing the need for system-wide field investigations and improving effectiveness of leak detection efforts. By identifying and repairing leaks earlier, the District is able to reduce real water losses, improve system efficiency, and recover water that would otherwise be lost.

Advanced Metering Infrastructure (AMI) and Customer Leak Detection The District continues to expand its AMI system, with approximately 85 percent of service connections currently equipped with cellular endpoints. The AMI platform provides near real- time water use data and includes automated leak detection capabilities that identify continuous water use over a 24-hour period. District staff proactively review these alerts and contact customers to notify them of potential leaks. In 2025, the District assisted in identifying and resolving 158 customer-side leaks as of November 26. These efforts support customer awareness, reduce unnecessary water use, and help prevent prolonged water losses at the customer level.

11.6.2.2 Planned DMM Activities

At this time, the District does not anticipate implementing new demand management programs beyond those currently in place. The District’s existing DMMs provide a comprehensive framework for promoting efficient water use and will continue to be implemented and refined as necessary to meet evolving regulatory requirements and operational needs. The District remains committed to efficient and responsible use of water resources and will continue to evaluate opportunities to enhance existing programs, incorporate new technologies, and improve program effectiveness over time. This includes ongoing efforts to reduce system losses, expand metering and data capabilities, and support customer awareness and conservation practices. Consistent with applicable State requirements, including UWUO provisions, the District will continue to monitor water use and adjust its demand management approach as needed to support long-term water use efficiency and regulatory compliance.

11.6.3 Water Shortage Contingency Plan
The District has adopted a Water Shortage Contingency Plan (WSCP) in accordance with CWC Section 10632. The WSCP establishes a structured framework for managing water supply shortages through defined shortages levels, corresponding response actions, and ongoing monitoring of water supply and demand conditions. The WSCP is designed to ensure that the District can respond effectively to a range of water shortage conditions, from minor supply constraints to more severe drought scenarios. The plan identifies stages of water shortage based on severity of supply conditions and outlines the actions the District may implement to reduce demand, manage available supplies, and maintain essential public health and safety services.

The WSCP also incorporates procedures for evaluating water supply reliability, including coordination with the District’s Annual Water Supply and Demand Assessment, which serves as the primary mechanism for identifying and responding to changing water supply conditions on an ongoing basis. Public communication and outreach are integral components of the WSCP and are used to inform customers of water supply conditions, required conservation actions, and applicable restrictions during shortage events. The following subsections summarize key components of the District’s WSCP, including shortage levels, response actions, and monitoring and implementation procedures.

11.6.3.1 Summary of Water Shortage Levels and Response
Actions
The District’s WSCP establishes a series of defined water shortage levels that correspond to increasing degrees of supply constraint, associated demand reduction targets, and specific response actions. This staged framework enables the District to implement proportional measures to manage water use and maintain essential public health and safety services during periods of reduced supply. The WSCP includes six shortage levels, each associated with a targeted reduction in water use relative to normal conditions. As shortage conditions

intensify, the District may implement progressively more restrictive measures to reduce demand and manage available supplies. The general framework of shortage levels and representative response actions is summarized below:

Stage 1 – Up to 10% Shortage (Water Shortage Watch):

Increased public awareness and voluntary conservation measures, including enhanced outreach and education efforts.

Stage 2 – Up to 20% Shortage:

Implementation of additional conservation measures and initial water use restrictions, such as limitation on outdoor irrigation and reduction of non-essential water uses.

Stage 3 – Up to 30% Shortage:

Expansion of mandatory restrictions, including further limitations on outdoor water use, increased enforcement, and intensified conservation programs.

Stage 4 – Up to 40% Shortage:

Implementation of significant demand reduction measures, including stricter outdoor irrigation limitations, expanded enforcement actions, and potential adjustments to system operations.

Stage 5 - Up to 50% Shortage:

Implementation of severe restrictions on non-essential water use, increased enforcement measures, and additional operational actions to manage limited supplies.

Stage 6 – Up to 60% Shortage:

Implementation of emergency response measures necessary to protect public health and safety, including curtailment of non-essential uses and prioritization of critical water needs.

As water supply conditions change, the District may transition between shortage levels based on ongoing evaluation of supply availability, customer demand, and system conditions.

11.6.3.2 Summary of Monitoring Procedures and
Implementation
The District’s WSCP includes procedures for monitoring water supply and demand conditions and implementing appropriate response actions based on observed and anticipated conditions. These procedures ensure that shortage response actions are timely and commensurate with the severity of supply constraints. The District monitors key indicators of water supply reliability, including groundwater production, available supply allocations, customer demand, and system conditions. This information is used to evaluate supply

availability and inform decisions regarding the initiation, modification, and termination of water shortage stages.

The District’s Annual Water Supply and Demand Assessment serves as the primary mechanism for evaluating near-term supply reliability and informing implementation of shortage response actions. Additional detail regarding the Annual Assessment is provided in Subsection 11.5.4 Forecasting Water Use for DRA and Annual Assessment of Sub-Chapter 11.5 Water Use Characterization.

Implementation of the WSCP includes coordination among District staff and communication with customers and regional partners. When a water shortage stage is implemented, the District provides public notification of applicable restrictions and conservation measures and monitors compliance to ensure demand reduction targets are achieved.

Sub-Chapter 11.7 – Water System
Reliability and Drought Risk
Assessment
This sub-chapter evaluates the reliability of the District’s water supplies to meet projected demands under a range of hydrologic conditions, consistent with CWC Sections 10631 (c) and 10635. The analysis integrates the water supply characterization presented in Sub-Chapter

11.4 Water Supply and Infrastructure Characterization with the water use projections developed in Sub-Chapter 11.5 Water Use Characterization to assess the District’s ability to meet customer demands during normal, single dry, and multiple dry year conditions.

The reliability analysis considers the availability of the District’s water supplies, including groundwater production and supplemental supplies, in relation to projected customer demands over the planning horizon. This evaluation is intended to identify potential supply shortfalls and assess the District’s capacity to maintain reliable water service under varying conditions. In addition to the long-term reliability analysis, this sub-chapter incorporates the District’s Drought Risk Assessment, which evaluates water supply reliability over a five-year planning horizon under a sequence of dry conditions.

The results of this analysis provide the basis for evaluating the District’s water supply reliability and inform the implementation of the District’s WSCP, as described in Sub-Chapter

11.6 Water Conservation and Shortage Response.

11.7.1 Five-year Drought Risk Assessment
The DRA evaluates the District’s ability to meet projected water demands over a five-year planning horizon under a sequence of dry conditions. This assessment provides a forward- looking evaluation of water supply reliability and is intended to identify potential supply- demand imbalances under extended drought scenarios. Projected water demands for the DRA as based on the District’s unconstrained demand forecast described in Sub-Chapter 11.5 Water Use Characterization and are expressed on an annual basis over the five-year planning period. These demands reflect anticipated customer use absent implementation of shortage response actions.

Available water supplies are evaluated based on the District’s managed groundwater supplies, which include groundwater production, replacement water, make-up water, and transfers and exchanges available through MWA, as described in Sub-Chapter 11.4 Water Supply and Infrastructure Characterization. Under the terms of the MBA adjudication, the District has discretion in managing its groundwater production and associated supplemental supplies, allowing it to adjust its supply portfolio to meet projected demands during dry conditions.

The DRA compares projected water demands to available supplies to evaluate the District’s capacity to meet customer needs over the five-year period. Table 11-23 presents the results of this analysis, including projected demands, available supplies, and any resulting surplus or shortage for each year of the DRA planning horizon, with values rounded to the nearest five acre-feet.

T
ABLE 11-23: FIVE-YEAR DROUGHT RISK ASSESSMENT (AFY)
2026 2027 2028 2029 2030
Supply 14,180 14,250 14,320 14,390 14,435
Demand 14,180 14,250 14,320 14,390 14,435
Difference 0 0 0 0 0

11.7.2 Long-Term Service Reliability
The UWMPA directs urban water purveyors to analyze water supply reliability in a normal, single dry, and five consecutive dry years over a 20-year planning horizon. The 2025 UWMP Guidebook recommends extending that period to twenty-five (25) years to provide a guiding document for future land use and water supply planning through the next UWMP cycle. The District’s long-term service reliability reflects the recommended 25-year planning horizon anticipating a normal, single dry, and five consecutive dry years from 2025 – 2050.

11.7.2.1 Normal and Single Dry Conditions 2030 – 2050
The following analysis evaluates the District’s availability to meet projected water demands under normal and single dry year conditions for the 2030 through 2050 planning horizon. This evaluation compares available water supplies to projected customer demands to assess the District’s capacity to reliably meet water needs under varying hydrologic conditions. Under both normal and single dry year conditions, the District’s supplies are managed within the framework of the MBA adjudication, which provides flexibility in balancing groundwater production and supplemental supplies. As a result, available supplies are sufficient to meet projected demands throughout the planning horizon.

Table 11-24 presents the results of the normal and single dry year reliability analyses, including projected demands, available supplies, and resulting surplus or shortage for each timestep from 2030 through 2050. Values are rounded to the nearest five acre-feet.

TABLE 11-24: NORMAL AND SINGLE DRY YEAR WATER SUPPLY AND DEMAND THROUGH 2050 (AFY) Normal Year 2030 2035 2040 2045 2050
Supply 14,435 14,765 15,090 15,415 15,740
Demand 14,435 14,765 15,090 15,415 15,740
Difference 0 0 0 0 0

Single Dry Year 2030 2035 2040 2045 2050
Supply 14,435 14,765 15,090 15,415 15,740
Demand 14,435 14,765 15,090 15,415 15,740
Difference 0 0 0 0 0

11.7.2.2 Five Consecutive Dry Years 2030 – 2050
The following analysis evaluates the District’s ability to meet projected water demands over a five-year period of consecutive dry conditions for the 2030 through 2050 planning horizon.

This assessment provides a more conservative evaluation of water supply reliability by examining the potential effects of extended drought conditions on available supplies. Under multiple dry year conditions, the District continues to manage its supplies within the framework of the MBA adjudication, which allows for flexibility in balancing groundwater production and supplemental supplies. This managed approach enables the District to adjust its supply portfolio over time to meet projected demands, even during extended periods of drought.

Table 11-25 presents the results of the multiple dry year reliability analysis, including projected demands, available supplies, and any resulting surplus or shortage for each year of the five-year dry sequence. Values are rounded to the nearest five acre-feet.

Together, the available supplies, when paired against projected demand conditions, demonstrate that the District has sufficient supplies to meet water demands under five consecutive dry year conditions through 2050.

TABLE 11-25: FIVE CONSECUTIVE DRY YEARS WATER SUPPLY AND DEMAND THROUGH 2050 (AFY) 2030 2035 2040 2045 2050
Year 1
Supply 14,435 14,765 15,090 15,415 15,740
Demand 14,435 14,765 15,090 15,415 15,740
Difference 0 0 0 0 0
Year 2
Supply 14,500 14,830 15,155 15,480 15,805
Demand 14,500 14,830 15,155 15,480 15,805
Difference 0 0 0 0 0
Year 3
Supply 14,565 14,895 15,220 15,545 15,870
Demand 14,565 14,895 15,220 15,545 15,870
Difference 0 0 0 0 0
Year 4
Supply 14,635 14,960 15,285 15,610 15,935
Demand 14,635 14,960 15,285 15,610 15,935
Difference 0 0 0 0 0
Year 5
Supply 14,700 15,025 15,350 15,675 16,000
Demand 14,700 15,025 15,350 15,675 16,000
Difference 0 0 0 0 0

11.7.3 Annual Reliability Assessment
Each year, the District considers current supply and demand conditions and performs an Annual Water Supply and Demand Assessment pursuant to CWC Section 10632.1 to evaluate real time or near-term circumstances that are different than the DRA scenario. This assessment evaluates actual current water supply and use conditions for a prescribed 12- month forecast (July through the following June). Procedures for conducting the Annual Assessment are contained in the District’s Water Shortage Contingency Plan. The District has conducted the assessment as required by the CWC and will continue this planning exercise to provide a reliability assessment for then-current conditions regarding supplies and expected (unconstrained) demands.

11.7.4 Water Supply Reliability Summary
The District’s water supply portfolio is capable of meeting the water uses in its service area in normal, single dry, and five consecutive dry years from 2025 through 2050.

Sub-Chapter 11.8 – Energy Intensity
Analysis
Pursuant to CWC Section 10631.2, the District evaluates the energy intensity of its water supply and distribution system. Energy intensity is defined as the amount of energy used to extract, treat, and deliver water to customers and is typically expressed in kilowatt-hours per acre- foot (kWh/AF). The District’s water supply portfolio is primarily comprised of locally produced groundwater. As a result, energy use is largely associated with groundwater extraction and distribution within the District’s service area, rather than long-distance conveyance or advanced treatment processes.

The District continues to monitor energy use associated with its water system operations and will evaluate opportunities to improve operational efficiency where feasible. Total energy intensity is reported in Table 11-26.

T
ABLE 11-26: ENERGY INTENSITY - TOTAL UTILITY APPROACH FOR OCT 2024 THROUGH SEPT 2025 Sum of All Water Management Processes
Volume of Water Entering Process (acre-feet) 14,123
Energy Consumed (kWh) 15,856,213
Energy Intensity (kWh/acre-foot) 1,123

Chapter 12.0 HI-DESERT WATER

DISTRICT

This page is reserved for Chapter 12 – Hi-Desert Water District. The complete Hi-Desert Water District retail specific chapter is included in the full 2025 Mojave RUWMP and is adopted separately by Hi-Desert Water District.

Chapter 13.0 JOSHUA BASIN WATER

DISTRICT

This page is reserved for Chapter 13 – Joshua Basin Water District. The complete Joshua Basin Water District retail specific chapter is included in the full 2025 Mojave RUWMP and is adopted separately by Joshua Basin Water District.

Chapter 14.0 LIBERTY UTILITIES – APPLE
VALLEY

This page is reserved for Chapter 14 – Liberty Utilities – Apple Valley. The complete Liberty Utilities – Apple Valley retail specific chapter is included in the full 2025 Mojave RUWMP and is adopted separately by Liberty Utilities – Apple Valley.

Chapter 15.0 PHELAN PIÑON HILLS

COMMUNITY SERVICES DISTRICT

This page is reserved for Chapter 15 – Phelan Piñon Hills Community Services District. The complete Phelan Piñon Hills Community Services District retail specific chapter is included in the full 2025 Mojave RUWMP and is adopted separately by Phelan Piñon Hills Community Services District.

Chapter 16.0 VICTORVILLE WATER

DISTRICT

This page is reserved for Chapter 16 – Victorville Water District. The complete Victorville Water District retail specific chapter is included in the full 2025 Mojave RUWMP and is adopted separately by the City of Victorville

APPENDIX 1 – NOTICES

August 27, 2025

Notice of Intent to Prepare a Regional Urban Water Management Plan for the Mojave Region

This notice is to inform you that the urban water suppliers within the greater Mojave region are preparing a 2025 Regional Urban Water Management Plan (UWMP) pursuant to the California Water Code (CWC). All wholesale and retail urban water suppliers serving more than 3,000 customer connections are required to prepare an UWMP every five (5) years. The following urban water suppliers are collectively preparing this Regional UWMP:

City of Adelanto Water District
County Service Area 64
County Service Area 70 J
Helendale Community Services District
Hesperia Water District
Hi-Desert Water District
Golden State Water Company – Barstow System
Joshua Basin Water District
Liberty Utilities – Apple Valley Water Company
Mojave Water Agency
Phelan Piñon Hills Community Services District
Victorville Water District

The purpose of a Regional UWMP is to allow the urban water suppliers to coordinate and efficiently address the State’s requirements as mandated in the CWC through a regional representation of water supply reliability. While the Regional UWMP will provide overarching and consistent information on water supplier reliability, each urban retail supplier will also update its unique Water Shortage Contingency Plan (WSCP), tailored to its specific service area and operations. Each urban supplier will separately adopt the Regional UWMP and its unique WSCP by July 1, 2026.

In accordance with CWC Section 10642, which encourages “active involvement of diverse social, cultural, and economic elements of the populations” in preparing a UWMP, the public will, at a minimum, have the opportunity to participate in the planning process through public hearings anticipated to occur in April or May of 2026 as part of each urban supplier’s adoption process. A draft copy of the 2025 Regional UWMP will be made available for review prior to hearings, providing an opportunity for (1) Community input regarding water supply reliability; (2) Consideration of the economic impacts of complying with CWC status governing the Regional UWMP; and (3) Discussion of each agency’s WSCP.

Detailed information, including contacts for each agency, future public hearing notices, schedules, and draft plan materials, will be available at the Mojave Water Agency’s website at https://www.mojavewater.org/basin-management/regional-planning/urban-water-management- plan/, or at similar links hosted by each urban retail water supplier.

Questions regarding this notice or the 2025 Regional UWMP process may be directed to the appropriate retail agency using the contact information found on the website.

VV-44038753
NOTICE IS HEREBY GIVEN that Public Hearings will be held before the Hesperia City Council, City of Hesperia, California on the following date:

DATE OF HEARINGS: June 2, 2026 (Tuesday)
TIME OF HEARINGS: 6:30 p.m., or as soon thereafter as possible PLACE OF HEARINGS: City of Hesperia, Council Chambers, 9700 Seventh Avenue, Hesperia, CA 92345 FOR THE FOLLOWING PURPOSE:

NOTICE OF PUBLIC HEARING ON THE 2025 MOJAVE REGIONAL

URBAN WATER MANAGEMENT PLAN
NOTICE IS HEREBY GIVEN that the City of Hesperia, acting as the Board of Directors of the Hesperia Water District (District), will hold a public hearing to receive comments on the proposed 2025 Mojave Regional Urban Water Management Plan (RUWMP), which includes the Hesperia Water District Retail Chapter (Chapter 11), as well as the District’s Water Shortage Contingency Plan (WSCP).

The 2025 Mojave RUWMP is a regional planning document prepared collaboratively by the Mojave Water Agency (MWA) and participating urban water retail suppliers within the Mojave Region in accordance with the California Urban Water Management Planning Act. The RUWMP includes regional chapters addressing basin-wide water supplies, water demands, and water service reliability; the MWA Wholesale Urban Water Management Plan; and urban water retail supplier-specific chapters for each participating urban water supplier.

The Hesperia Water District Retail Chapter (Chapter 11) addresses conditions specific to the District’s service area, including water service and system description, population and land use, water supply and infrastructure, water use characterization, water conservation and shortage response, and water system reliability. The District’s WSCP describes the actions the District may implement to respond to water shortage conditions and maintain essential water service reliability.

The District is considering adoption of the regional chapters of the 2025 Mojave RUWMP, together with the Hesperia Water District Retail Chapter (Chapter 11) and the District’s Water Shortage Contingency Plan.

Copies of the draft 2025 Mojave RUWMP, including the Hesperia Water District Retailer Chapter (Chapter 11), and the District’s WSCP are available for public review at 9700 Seventh Avenue Hesperia, CA 92345 during regular business hours and online at https://hesperiaca.gov/1468/Urban-Water-Management-Plan.

Any person interested in the proposals may contact the City Clerk’s Office at 9700 Seventh Avenue, Hesperia, California, 760.947 .1007 during normal business hours. The pertinent information will be available for public inspection at the above address.

I, Jessica Giber, Assistant City Clerk to the City Council, Hesperia Community Development Commission, Hesperia Housing Authority, Successor Agency to the Redevelopment Agency and Water District do hereby certify that I caused to be posted the foregoing Notice of Public Hearings on Thursday, May 14, 2026 at 5:30 p.m. pursuant to California Government Code and Hesperia Resolution No. 2007 101.
_______________________________
Jessica Giber, Assistant City Clerk
City of Hesperia

NOTICE OF PUBLIC HEARINGS

APPENDIX 2 – REDUCED DELTA

RELIANCE

Appendix 2
Mojave Region Delta Reliance
This Appendix provides the Delta Reliance assessment for the Mojave Water Agency (MWA) and the RUWMP participating retail water service agencies located within the Mojave Region.

These retail agencies in the Mojave Region covered by this RUWMP assessment include:

Liberty Utilities – Apple Valley Water Company, City of Adelanto Water District, San Bernardino County Service Area 64, San Bernardino County Service Area 70J, Golden State Water Company – Barstow System, Hesperia Water District, Hi-Desert Water District, Joshua Basin Water District, Phelan Piñon Hills Community Services District, and Victorville Water District.

These retail agencies are subject to the minimum threshold requirements of the Urban Water Management Planning Act (UWMP Act) and work with MWA on managing regional water supplies as described more thoroughly in the 2025 RUWMP. Additional entities that are not currently subject to the UWMP Act but may subject to the UWMP Act in the future and that rely upon water supplies derived from MWA’s and the retail agencies’ management are also considered in this assessment. Last, this assessment is consistent with all applicable water management activities within the Region including the Mojave Basin Area Adjudication Judgement, the Warren Valley Basin Judgment, and the Ames/Reche Groundwater Storage and Recovery Program Management Agreement.

A.1 Delta Reform Act and Certification of Consistency
The Delta Reform Act of 2009 required state and local agencies to prepare a written certification of consistency with Delta Plan policies before initiating a covered action in the Delta.1 The written certification of consistency must be submitted to the Delta Stewardship Council and include detailed findings as to whether the covered action is consistent with applicable Delta Plan policies.2 The submitted certification of consistency may be appealed by any person and the Delta Stewardship Council may grant the appeal to address contested issues.3 In short, water suppliers that anticipate participating in a proposed covered action must comply with the requirements of the Delta Reform Act. 1 California Water Code section 85057.5.
2 California Water Code section 85225.
3 California Water Code section 85225.10-85225.25.

Proposed covered actions may include a conveyance facility or a new diversion that involves transferring water through, exporting water from, or using water in the Delta. For urban purveyors that may participate in a proposed covered action, should provide information in their Urban Water Management Plans (UWMP) that can be used to demonstrate consistency with the Delta Plan. Specifically, the urban purveyors need to demonstrate consistency with Delta Plan Policy WR P1 – Reduce Reliance on the Delta Through Improved Regional Water Self-Reliance (WR P1).4 WR P1 subsection (a) states that:

Water shall not be exported from, transferred through, or used in the Delta if all of the following apply:
(1) One or more water suppliers that would receive water as a result of the export, transfer, or use have failed to adequately contribute to reduced reliance on the Delta and improved regional self-reliance consistent with all of the requirements listed in paragraph (1) of subsection (c); (2) That failure has significantly caused the need for the export, transfer, or use; and
(3) The export, transfer, or use would have a significant adverse environmental impact in the Delta.

WR P1 subsection (c)(1) further defines what adequately contributing to reduced reliance on the Delta means in terms of (a)(1) above. WR P1 subsection (c)(1) states:

Water suppliers that have done all the following are contributing to reduced reliance on the Delta and improved regional self-reliance and are therefore consistent with this policy:
(A) Completed a current Urban or Agricultural Water Management Plan (Plan) which has been reviewed by the California Department of Water Resources for compliance with the applicable requirements of Water Code Division 6, Parts 2.55, 2.6, and 2.8;
(B) Identified, evaluated, and commenced implementation, consistent with the implementation schedule set forth in the Plan, of all programs and projects included in the Plan that are locally cost effective and technically feasible which reduce reliance on the Delta; and
4 Cal. Code Regs., tit. 23 section 5003.

(C) Included in the Plan, commencing with 2015, the expected outcome for measurable reduction in Delta reliance and improvement in regional self- reliance. The expected outcome for measurable reduction in Delta reliance and improvement in regional self-reliance shall be reported in the Plan as the reduction in the amount of water used, or in the percentage of water used, from the Delta watershed. For the purposes of reporting, water efficiency is considered a new source of water supply, consistent with Water Code section 1011(a).

The analysis in this RUWMP Appendix includes all of the elements described in WR P1(c)(1) that need to be included in a water supplier’s UWMP to support a certification of consistency for a future proposed covered action.

A.2 Expected Outcomes for Reduced Delta Reliance and
Regional Self Sufficiency
The expected outcomes for this Delta reliance and improved regional self-reliance assessment were developed using guidance described in Appendix C of DWR’s Urban Water Management Plan Guidebook 2025, issued in January 2026 (Guidebook 2025), which generally reflected the guidebook issued in March 2021 (Guidebook 2020). The data used in this assessment represent the total regional efforts of MWA and the retail agencies and were developed as part of a region-wide coordination process to prepare the 2025 Regional Urban Water Management Plan (RUWMP).

Table 1 shows the expected outcomes for reduced Delta
reliance within the Mojave Region.

TABLE 1: EXPECTED OUTCOMES FOR REDUCED RELIANCE ON THE DELTA Year 2010 2015 2020 2025 2030 2035 2040 2045 2050
Total Water Supplies
from the Delta
Watershed 34.2% 34.2% 31.0% 26.1% 24.6% 23.5% 22.9% 22.3% 21.7% Change in Water
Supplies from the Delta
Watershed -0.1% -3.3% -8.2% -9.6% -10.7% -11.4% -12.0% -12.5%

The methodology for demonstrating reduced reliance on the Delta is consistent with DWR’s Guidebook 2020 and Guidebook 2025. MWA calculated its expected outcomes for reduced Delta reliance by measuring its current and anticipated water use against a baseline condition. MWA chose 2010 normal water year as its baseline. Data for the 2010 baseline

were taken from relevant regional planning documents. MWA then assessed its Delta Reliance against the 2010 baseline for years 2015 through 2050.

The analysis uses normal water year demands to assess the supplies that would be used in the future. In addition, because WR P1 considers water use efficiency savings as a source of supply, prior the UWMP Act water conservation mandates (e.g. 20% by 2020) and more recent requirements that help support water use efficiency quantification in the Region .5 Table 2
shows the Region’s water demands without water use efficiency and the reported water use efficiency.

TABLE 2: DEMANDS WITHOUT WATER USE EFFICIENCY
Total Service
Area Water
Demands
(Acre-Feet)
2010 2015 2020 2025 2030 2035 2040 2045 2050
Water
Demands with
Water Use
Efficiency
145,066 138,009 129,595 121,700 123,400 125,000 126,500 128,800 130,700 Reported
Water Use
Efficiency
- 17,735 38,571 72,800 77,112 81,378 85,682 89,024 92,557 Water
Demands
without Water
Use Efficiency
145,066 155,744 168,166 194,500 200,512 206,378 212,182 217,824 223,257

MWA and the participating retail urban water suppliers must also report the expected outcomes for measurable improvement in regional self-reliance. Given water management within the Region as described throughout the 2025 RUWMP, Table 3 shows the expected outcomes for supplies contributing to regional self-reliance for the Region as a whole. 5 In 2018, the California Legislature passed Senate Bill 606 and Assembly Bill 1668, directing the SWRCB to adopt standards to encourage more efficient urban water use. This legislation, known as "Making Conservation a California Way of Life," was adopted in 2024, establishing individualized Urban Water Use Objectives for each urban retail water supplier. In contrast to the SB X7-7 per-capita targets, this legislation functions as a water budget tailored to a supplier’s service area, considering residential indoor use, residential and commercial outdoor use based on local evapotranspiration and irrigable landscape area, water loss, and bonus incentives for potable reuse. In addition to the volumetric UWUO, the regulation establishes performance measures for commercial, industrial, and institutional sectors. The standards become progressively more stringent through 2040.

The data presented in this section demonstrate the expected outcomes for reduced Delta reliance and regional self-sufficiency. The information has been noticed and presented in accordance with applicable law.

TABLE 3: SUPPLIES CONTRIBUTING TO REGIONAL SELF-RELIANCE Water Supplies
Contributing to
Regional Self-
Reliance
2010 2015 2020 2025 2030 2035 2040 2045 2050
Water Use
Efficiency
0 17,735 38,571 72,800 77,112 81,378 85,682 89,024 92,557 Water Recycling 62,000 47,825 52,536 47,495 49,699 50,930 52,172 53,559 53,560 Conjunctive Use
Projects
54,045 57,349 57,349 57,349 57,349 57,349 57,349 57,349 57,350 Water Supplies
Contributing to
Regional Self-
Reliance
116,045 122,909 148,456 177,644 184,160 189,658 195,203 199,932 203,466

Service Area
Water Demands
without Water
Use Efficiency
2010 2015 2020 2025 2030 2035 2040 2045 2045
Service Area Water
Demands without
Water Use
Efficiency

145,066

155,744

168,166

194,500

200,512

206,378

212,182

217,824

223,257

Change in
Regional Self
Reliance (Acre -
Feet)
2010 2015 2020 2025 2030 2035 2040 2045 2045
Water Supplies
Contributing to
Regional Self-
Reliance

116,045

122,909

148,456

177,644

184,160

189,658

195,203

199,932

203,466
Change in Water
Supplies
Contributing to
Regional Self-
Reliance

6,864

32,411

61,599

68,115

73,613

79,158

83,887

87,421

Percent Change in
Regional Self
Reliance
2010 2015 2020 2025 2030 2035 2040 2045 2045
Water Supplies
Contributing to
Regional Self-
Reliance

80.0% 78.9% 88.3% 91.3% 91.8% 91.9% 92.0% 91.8% 91.1%
Change in
Water Supplies
Contributing to
Regional Self-
Reliance
-1.1% 8.3% 11.3% 11.9% 11.9% 12.0% 11.8% 11.1%

APPENDIX 3 - MWA REGIONAL

DWR CHECKLIST

APPENDIX 4 – MWA WSCP

Mojave Water Agency
Water Shortage Contingency Plan

Water Shortage Contingency Plan
This Water Shortage Contingency Plan (WSCP) addresses the plan preparation requirements in Water Code Section 10632 of the Urban Water Management Planning Act (The Act). The WSCP is incorporated into the 2025 Urban Water Management Plan (UWMP) and used by Mojave Water Agency (MWA) to respond to water shortage contingencies in the MWA service area as they may arise.

MWA provides wholesale water to retail agencies within its service area. The retail agencies are the direct purveyor of water service to retail customers. As such, MWA relies on a coordinated approach to water shortage management with the retail water agencies within its service area. MWA’s efforts in Water Shortage Contingency Planning are focused on maintaining and augmenting groundwater supplies in order to mitigate against extended drought conditions and catastrophic water outages. And because MWA is a wholesale urban water supplier, elements that pertain only to retail water suppliers are not addressed in this WSCP.
1 This chapter will address all aspects of MWA’s WSCP actions and address specific outage scenarios that MWA’s water management actions alleviate.

Section 10631 of the Urban Water Management Plan Act lists the following required elements for wholesale water purveyors:

1. An analysis of water supply reliability

2. Procedures for conducting an annual water supply and demand assessment

3. Six standard water shortage levels corresponding to progressive ranges of up to 10, 20, 30, 40, and 50 percent shortages and greater than 50 percent shortage and the shortage response actions that align with the defined shortage levels.

4. Communication protocols and procedures

5. A description of legal authorities

6. A description of financial consequences

7. Reevaluation and improvement procedures

8. Special Water Feature Distinction (10632(b))
1 Water Code sections 10632(a)(6), 10632(a)(8)(C), and 10632(a)(9) apply exclusively to retail urban purveyors.

9. Plan Adoption, Submittal, and Availability
This WSCP is a stand-alone plan that may be adopted independently from the UWMP and may be amended or refined and readopted as needed over coming months and years independently from the UWMP.

1.1 Water Supply Reliability Analysis
Mojave Water Agency is a special act district created in 1960 under Chapter 97 of the California Water Code Water Appendices. MWA service area covers 4,900 square miles in San Bernardino County and delivers water for regional groundwater management that is used by numerous retail water purveyors, ten of which are required to prepare an UWMP under the Urban Water Management Planning Act. Regional water supplies consist of naturally recharged groundwater, return flows, wastewater imports and imported State Water Project supplies. These supplies are discussed in greater detail in Chapter 4.

The water demands in the MWA service area currently serve a population approaching 600,000 people that is expected to grow to nearly 700,000 people by 2065. 2 MWA’s service
area demand analysis includes both the population assessment and relevant land use information provided by each retail provider. In short, the MWA service area demands are set to increase from 121,250 acre-feet per year in 2030 to over 126,000 acre-feet per year in 2045.

Moreover, MWA’s regional demands projection for 2050 exceed 127,270 acre-feet. These long-term demands are included in the 2025 UWMP in order to improve long-term water management and planning actions. These demands are discussed in detail in Chapter 6.

MWA has sufficient available regional supplies to meet the regional demands through 2050.

These supplies include not only the sources noted above, but also stored water within the SWP system and groundwater storage within the MWA service area. In concert with the supplies noted above, these stored supplies allow MWA to provide reliable water supplies to retail agencies in dry year conditions. Accordingly, as shown in Chapter 4, MWA has reliable water supplies available to meet normal, single dry, and five consecutive dry year water demands through 2065.
2 Mojave Water Agency Population Forecast, 2020 Edition, August 2020, UC Riverside School of Business Center for Economic Forecasting and Development

1.2 Annual Water Supply and Demand Assessment
Procedures
The WSCP describes MWA’s procedural methodology for managing shortages and developing its Annual Water Supply and Demand Assessment (Annual Assessment). The Annual Assessment will be submitted to DWR by July 1 each year with the first Annual Assessment due July 1, 2022. The Annual Assessment examines MWA’s anticipated water reliability for the current year and one additional dry year to determine what, if any, water shortages stages may be triggered during the required period. The Annual Assessment will be used by MWA decisionmakers to prepare for and initiate implementation of any needed response actions, as well as to inform customers, the general public, interested parties, and local, regional, and state government entities to prepare for such required actions, if necessary.

1.2.1 Analytical and Decision-making Processes
MWA plans to conduct its Annual Assessment according to the following timeline and process:

By February 1 Initial data collection, analysis, and coordination with retail agencies By March 1 Preliminary Draft Annual Assessment subject to internal review By April 1 Draft Annual Assessment and results briefing for MWA decision-makers By May 1 Approval of Annual Assessment to MWA Decision-makers By June 1 Public Release of Annual Assessment and Public Notifications By July 1 Submit Annual Assessment to DWR in advance of July 1 deadline MWA will prepare its Annual Assessment using the following key data and analytical methods:
• Prepare supply estimates for each water source for the analysis period. • Update unconstrained regional demand and estimate anticipated actual water use for the analysis period.
• Update infrastructure assessment, including estimated water supply production capability on a monthly basis for the analysis period.
• Identify and quantify any locally applicable factors that may influence or disrupt supplies during the analysis period.

For the purposes of conducting the Annual Assessment, MWA’s definition of “dry year” mimics characteristics of 2021-2022 water year where SWP allocation was 5%.

1.2.2 Submittal Procedure
MWA will submit its Annual Assessment to DWR via email by July 1 each year. At the time of DWR submittal, MWA will also notify all retail water agencies, the public, and other stakeholders concerning the results of the Annual Assessment and where it is available for review.

1.3 Six Standard Water Shortage Stages and Shortage
Response Actions
The WSCP requires water suppliers to adopt six water shortage stages, which correspond to progressively severe water shortage conditions (up to 10%, 20%, 30%, 40%, 50%, and greater than 50% percent shortage) as compared to the normal reliability condition. These water shortage stages have been standardized to allow for a consistent regional and statewide approach to conveying the relative severity of water supply shortage conditions. Changes in supply availability will trigger an appropriate water shortage stage. MWA will then implement the response actions as specified below.

The WSCP is required to identify locally appropriate shortage response actions that align with the defined shortage stages and include demand reduction actions, supply augmentation actions, system operational changes, and mandatory prohibitions against specific water use practices that are in addition to state-mandated prohibitions and appropriate to the local conditions. For each response action the WSCP is to provide an estimate of the extent to which the gap between supplies and demand will be reduced by implementation of the action.

MWA has grouped the actions to be taken during a water shortage condition into six stages, providing flexibility to address water shortages up to and exceeding the 50 percent shortage level condition. The following is an overview of the staged response MWA could follow during a given water shortage condition including sequential Stages (1-6) based on shortage severity, relative supply conditions for each stage, and percent shortage reduction levels.

MWA will adopt the six standard water shortage stages for this 2025 WSCP as shown in Table 1 below.

Table 1: Shortage Stages and Response Actions
Shortage
Stage
Shortage
Percentage Shortage Response
1 Up to 10% • Access Stored Supplies, as
needed
• Access Flexible Supplies, as
needed
• Implement Voluntary Demand
Reduction
• 0-100% met by Storage
• 0-100% met by Flexible Supplies
• 0-10% met by communicating voluntary
demand reduction
2 10%-20% • Access Stored Supplies, as
needed
• Access Flexible Supplies, as
needed
• Implement Voluntary Demand
Reduction
• Reduce R
3 Deliveries
• 0-100% met by Storage
• 0-100% met by Flexible Supplies
• 0-20% met by communicating voluntary
demand reduction
• 0-20% through reduced R3 deliveries
3 20%-30% • Access Stored Supplies, as
needed
• Access Flexible Supplies, as
needed
• Implement Voluntary Demand
Reduction
• Reduce R
3 Deliveries
• 0-100% met by Storage
• 0-100% met by Flexible Supplies
• 0-30% met by communicating voluntary
demand reduction
• 0-30% through reduced R3 deliveries
4 30%-40% • Access Stored Supplies, as
needed
• Access Flexible Supplies, as
needed
• Implement Voluntary Demand
Reduction
• Reduce R
3 Deliveries
• 0-100% met by Storage
• 0-100% met by Flexible Supplies
• 0-30% met by communicating voluntary
demand reduction
• 0-30% through reduced R3 deliveries
5 40%-50% • Access Stored Supplies, as
needed
• Access Flexible Supplies, as
needed
• Implement Voluntary Demand
Reduction
• Reduce R3 Deliveries
• 0-100% met by Storage
• 0-100% met by Flexible Supplies
• 0-30% met by communicating voluntary
demand reduction
• 0-30% through reduced R3 deliveries
6 More than 50% • Access Stored Supplies, as
needed
• Access Flexible Supplies, as
needed
• Implement Voluntary Demand
Reduction
• Reduce R
3 Deliveries
• 0-100% met by Storage
• 0-100% met by Flexible Supplies
• 0-30% met by communicating voluntary
demand reduction
• 0-30% through reduced R3 deliveries

Stage 1 (up to 10 percent shortage) – When Stage 1 is implemented, voluntary water conservation is encouraged. The drought situation is explained to the public and governmental bodies. MWA explains the possible subsequent water shortage stages in order to forecast possible future actions for the retail agencies. The activities performed by MWA during this stage include, but are not limited to:
• Implementation of all Voluntary Water Conservation Measures to a level addressing up to 10% water conservation savings.
• Public information campaign consisting of distribution of literature, speaking engagements, website updates, bill inserts, and conversation messages printed in local newspapers.
• Educational programs in area schools.
• Initiating a Conservation Hotline, a toll-free number with trained Conservation Representatives to answer customer questions about conservation and water use efficiency.
• Access stored supplies to address supply deficits, as needed • Access alternative water supplies to address supply deficits, as needed Stage 2 (11 - 20 percent shortage) – When Stage 2 is implemented, voluntary water conservation is strongly encouraged. MWA coordinates actions with regional retail water purveyors. The drought situation is explained to the public and governmental bodies. MWA explains the possible subsequent water shortage stages in order to forecast possible future actions for the customer base. The activities performed by MWA during this stage include, but are not limited to:
• Implementation of all Voluntary Water Conservation Measures to a level addressing up to 20% water conservation savings.
• Public information campaign consisting of distribution of literature, speaking engagements, website updates, bill inserts, and conversation messages printed in local newspapers.
• Educational programs in area schools.
• Expanding the Conservation Hotline, a toll-free number with trained Conservation Representatives to answer customer questions about conservation and water use efficiency.
• Access stored supplies to address supply deficits, as needed • Access alternative water supplies to address supply deficits, as needed

• Reduce R3 deliveries as appropriate with retail agencies Stage 3 (21 - 30 percent shortage) – When Stage 3 is implemented, voluntary water conservation is strongly encouraged and demand reduction measures are repeatedly communicated. MWA coordinates actions with regional retail water purveyors and emphasizes MWA’s ability to assist with supply re-allocation. The seriousness of the drought situation is explained to the public and governmental bodies. MWA explains the possible subsequent water shortage stages in order to forecast possible future actions for the customer base. The activities performed by MWA during this stage include, but are not limited to:
• Implementation of all Voluntary Water Conservation Measures to a level addressing up to 30% water conservation savings.
• Aggressive public information campaign consisting of distribution of literature, speaking engagements, website updates, bill inserts, and conversation messages printed in local newspapers.
• Educational programs in area schools.
• Expanding the Conservation Hotline, a toll-free number with trained Conservation Representatives to answer customer questions about conservation and water use efficiency.
• Access stored supplies to address supply deficits, as needed • Access alternative water supplies to address supply deficits, as needed • Reduce R3 deliveries as appropriate with retail agencies Stage 4 (31 - 40 percent shortage) – When Stage 4 is implemented, voluntary water conservation is strongly encouraged and demand reduction measures are repeatedly communicated. MWA coordinates actions with regional retail water purveyors and assesses opportunities for supply reallocation among participating retail water purveyors. The seriousness of the drought situation is explained to the public and governmental bodies.

MWA explains the possible subsequent water shortage stages in order to forecast possible future actions for the customer base. The activities performed by MWA during this stage include, but are not limited to:
• Implementation of all Voluntary Water Conservation Measures to a level addressing up to 30% water conservation savings.
• Aggressive public information campaign consisting of distribution of literature, speaking engagements, website updates, bill inserts, and conversation messages printed in local newspapers.

• Educational programs in area schools.
• Expanding the Conservation Hotline, a toll-free number with trained Conservation Representatives to answer customer questions about conservation and water use efficiency.
• Access stored supplies to address supply deficits, as needed • Access alternative water supplies to address supply deficits, as needed • Reduce R3 deliveries as appropriate with retail agencies Stage 5 (41 - 50 percent shortage) – When Stage 5 is implemented, voluntary water conservation is stressed to all regional purveyors and demand reduction measures are repeatedly communicated. MWA coordinates actions with regional retail water purveyors and assesses opportunities for supply reallocation among participating retail water purveyors. The dire situation caused by the water shortage is explained to the public and governmental bodies. MWA explains the possible subsequent water shortage stages in order to forecast possible future actions for the customer base. The activities performed by MWA during this stage include, but are not limited to:
• Implementation of all Voluntary Water Conservation Measures to a level addressing up to 30% water conservation savings.
• Aggressive public information campaign consisting of distribution of literature, speaking engagements, website updates, bill inserts, and conversation messages printed in local newspapers.
• Educational programs in area schools.
• Expanding the Conservation Hotline, a toll-free number with trained Conservation Representatives to answer customer questions about conservation and water use efficiency.
• Access stored supplies to address supply deficits, as needed • Access alternative water supplies to address supply deficits, as needed • Reduce R3 deliveries as appropriate with retail agencies Stage 6 (greater than 50 percent shortage) – When Stage 6 is implemented, voluntary water conservation is stressed to all regional purveyors and demand reduction measures are repeatedly communicated. MWA coordinates actions with regional retail water purveyors and assesses opportunities for supply reallocation among participating retail water purveyors. The emergency situation caused by the water shortage is explained to the public and governmental bodies. MWA explains conditions leading to supply reductions to all retail purveyors. The activities performed by MWA during this stage include, but are not limited to:

• Implementation of all Voluntary Water Conservation Measures to a level addressing up to 30% water conservation savings.
• Aggressive public information campaign consisting of distribution of literature, speaking engagements, website updates, bill inserts, and conversation messages printed in local newspapers.
• Educational programs in area schools.
• Expanding the Conservation Hotline, a toll-free number with trained Conservation Representatives to answer customer questions about conservation and water use efficiency.
• Access stored supplies to address supply deficits, as needed • Access alternative water supplies to address supply deficits, as needed • Reduce R3 deliveries as appropriate with retail agencies

1.3.1 Supply Augmentation Actions
The following water supply augmentation actions may be used as response actions for the appropriate Water Shortage Stage. MWA may access its stored water sources in various locations inside and outside its service area. This storage occurs as carryover water in the SWP as well as groundwater storage within the MWA Service Area. These stored supplies may be transferred or exchanged with other purveyors that can assist in providing water supplies to MWA’s service area. In addition, MWA will work with the California Department of Water Resources (DWR) to access supplies that may be made available in the statewide conveyance systems. Lastly, MWA may take additional supply augmentation actions that become available during the identified water shortage condition like acquiring water from other entities through transfers or exchanges that may be delivered into MWA’s service area.

1.3.2 Operational Changes
The following water system operational changes may be used as response actions for the appropriate Water Shortage Stage. MWA may use its water storage and conveyance facilities to expedite water acquisitions, transfers, and exchanges that may alleviate identified water shortage conditions. MWA will assess the utility associated with full operational capacity at its R
3 facility and coordinate operational actions with retail agencies that will help address water shortage conditions. Moreover, where operational flexibility exists in MWA’s six turnouts from the East Branch of the State Water Project, MWA may exercise operational options to facilitate water shortage mitigation actions.

1.3.3 Emergency Response Plan for Catastrophic Water Shortages This section identifies actions to be undertaken by MWA to prepare for, and implement during, a catastrophic interruption of water supplies. A catastrophic interruption could result from natural and man-made events that causes a water shortage severe enough to trigger a Stage 1-6 water supply shortage condition. In addition, MWA’s SWP water supplies are conveyed through the California Aqueduct system operated by DWR, and DWR has created several emergency plans to address catastrophic outages. This section addresses the catastrophic outage scenarios and relevant actions that MWA will undertake should a catastrophic outage occur.

Earthquakes are an issue of concern in the Mojave Basin region. The southern portion of the San Andreas Fault borders the western edge of Mojave Water Agency’s Service Area and an earthquake on that fault could significantly impact water service and infrastructure. The California Department of Water Resources (DWR) has noted that an earthquake could damage the California Aqueduct conveyance system through structural damage or electrical failures which could potentially halt water deliveries to MWA. In short, an earthquake may create regional turmoil that could impact local infrastructure or cause power outages for extended periods of time.

DWR has a contingency California Aqueduct outage plan for restoring the California Aqueduct to service should a major break occur because of an earthquake or other catastrophic reason. DWR estimates that a major break in the California Aqueduct would take approximately four months to repair. Although extended water supply shortages may manifest for MWA’s imported water supplies, the retail agencies and MWA have alternative water supplies available to meet fundamental customer demands. Retail agencies have access to managed groundwater throughout the MWA Service Area and MWA has stored imported water supplies that could be used to meet crisis conditions. Local effects of a catastrophic outage on local water systems may require additional cooperative efforts among regional water purveyors.

In addition to earthquakes, the SWP could experience other emergency outage scenarios.

Past examples include slippage of aqueduct side panels into the California Aqueduct near Patterson in the mid-1990s, the Arroyo Pasajero flood event in 1995 (which also destroyed part of Interstate 5 near Los Baños), flood damage to the East Branch of the Aqueduct in 2015, and historic subsidence and leakage repairs needed along the Main Branch and East Branch of the Aqueduct since the 1980s, and potential for further subsidence issues being identified as recently as 2025. All of these outages were short-term in nature (on the order of weeks to several months), and DWR’s Operations and Maintenance Division worked diligently to devise methods to keep the Aqueduct in operation and continue SWP deliveries while repairs were

made. Thus, the SWP contractors generally experienced no interruption in total annual deliveries but local actions to mitigate the outage were implemented.

It is important to note that all of MWA’s SWP imported supply is used to replenish groundwater recharge facilities. These groundwater augmentation efforts insulate regional purveyors against an outage of the SWP system. As noted in Chapter 4, MWA has over 200,000 acre- feet of stored water available for extraction and use in the MWA service area. Combining this stored water with other stored supplies by the local retail agencies as well as the existing groundwater supplies in the region, MWA and its wholesale member agencies may sustain water supplies in a catastrophic outage of the SWP delivery systems. Even an interruption in SWP supplies for several months would not provide any immediate threat to potable water deliveries from groundwater production wells.

MWA developed its Regional Recharge and Recovery Project, known as “R³,” to increase flexibility in its water system. The R³ project is a basin management tool and conjunctive use project that distributes stored water via groundwater wells pumping from the Mojave Basin to local retail water purveyors. This groundwater pumping production is done to benefit each of the retail water agencies and in lieu of pumping from other groundwater production facilities of these retail agencies. This groundwater management project allows water to be pumped in a portion of the basin to be used in lieu of other groundwater production in other portions of the basin so that the various areas of the basin can be actively managed. The R 3 project
includes groundwater recharge facilities, groundwater production wells, booster pumps, storage reservoirs, interconnections to the retail customer water system, water meters, and chlorination facilities. The R
3 facilities provide redundant capacity to the retail agencies during catastrophic outage events. Although MWA may stop deliveries in the R3 facilities to the retail agencies at any time, the facilities may help provide water supplies during crisis conditions. In short, working in parallel with the retail agencies, the R3 facilities can be used to supplement the facilities that each retail water agency may have to handle catastrophic outages.

The R3 facilities also have a separate Emergency Response Plan (ERP).3 This ERP identifies emergency procedures, response actions, and responsible personnel that would be activated in the event of an emergency with the R
3 facilities. Specifically, the ERP addresses responses to leaks or service interruptions, low pressure, power outage, contamination, and physical destruction of the R
3 facilities.4 Accordingly, MWA’s R3 ERP provides an additional buffer against emergency and catastrophic outage that may impact Statewide, regional, or local water distribution and treatment facilities.
3 R3 System Emergency/Disaster Response Plan Update 2019, Mojave Water Agency. 4 ERP at 2-3.

The area’s water sources are generally of good quality, and no insurmountable problems resulting from industrial or agricultural contamination are foreseen. If contamination did result from a toxic spill or similar problematic event, the contamination would be isolated and should not significantly impact the total water supply in the region. In addition, such an event would be addressed in the retailers’ emergency response plan as well as the R 3 ERP.

1.3.4 SWP Emergency Outage Scenarios
There are numerous events that could result in significant outages and potential interruption of service. Examples of possible nature-caused events include a levee breach in the Delta near the Harvey O. Banks Pumping Plant, a flood, an earthquake event that severely damages the California Aqueduct along its San Joaquin Valley traverse, or an earthquake event along the East Branch of the California Aqueduct. Such events could impact some or all SWP contractors south of the Delta.

The response of DWR, MWA, and other SWP contractors to such events would be highly dependent on the type and location of any such event. In typical SWP operations, water flowing through the Delta is diverted at the SWP’s main pumping facility, located in the southern Delta, and is pumped into the California Aqueduct. During the relatively heavier runoff period in the winter and early spring, Delta diversions generally exceed SWP contractor demands, and the excess is stored in San Luis Reservoir. The SWP California Aqueduct terminal reservoirs, such as Pyramid and Castaic Lakes, are also replenished during these periods. During the summer and fall, when diversions from the Delta are generally more limited and less than contractor demands, releases from San Luis Reservoir are used to make up the difference in deliveries to contractors. The SWP share of storage capacity at San Luis Reservoir is 1,062,000 AF.

MWA receives its SWP deliveries through the East Branch of the California Aqueduct. The other contractors receiving deliveries from the East Branch are Metropolitan Water District, Antelope Valley-East Kern Water Agency, Palmdale Water District, Crestline-Lake Arrowhead Water Agency, Desert Water Agency, San Gabriel Valley Municipal Water District, San Bernardino Valley Municipal Water District, San Gorgonio Pass Water Agency, and Coachella Valley Water District. The East Branch has two terminal reservoirs, Silverwood Lake and Lake Perris, which were designed to provide emergency storage and regulatory storage (i.e., storage to help meet peak summer deliveries) for several of the East Branch contractors.

However, MWA does not have contract rights to storage capacity in those reservoirs.

Silverwood Lake is within the MWA service area and releases from the lake flow into the primary groundwater basins within the MWA service area. In addition to SWP storage south of the Delta in San Luis Reservoir and the terminal reservoirs, a number of contractors have stored water in groundwater banking programs in the San Joaquin Valley and more recently

along the East Branch, and many also have surface and groundwater storage within their own service areas.

Three scenarios that could impact the delivery to MWA of its SWP supply or other supplies delivered to it through the California Aqueduct are described below. For each of these scenarios, it was assumed that an outage of six months could occur. MWA’s ability to meet demands during the worst of these scenarios is presented following the scenario descriptions.

Scenario 1: Levee Breach near the Sacramento-San Joaquin Delta The California Department of Water Resources (DWR) has estimated that in the event of a major earthquake in or near the Delta, regular water supply deliveries from the SWP could be interrupted for up to three years, posing a substantial risk to the California business economy.

Accordingly, a post-event strategy has been developed which would provide necessary water supply protections. The plan has been coordinated through DWR, the Army Corps of Engineers (Corps), Bureau of Reclamation, California Office of Emergency Services (Cal OES), the Metropolitan Water District of Southern California, and the State Water Contractors. Full implementation of the plan would enable resumption of at least partial deliveries from the SWP in less than six months.

DWR Delta Flood Emergency Management Plan (“Emergency Pathway”). DWR has developed the Delta Flood Emergency Management Plan to provide strategies for a response to Delta levee failures, which addresses a range of failures up to and including earthquake- induced multiple island failures during dry conditions when the volume of flooded islands and saltwater intrusion are large. Under such severe conditions, the plan includes a strategy to establish an emergency freshwater pathway from the central Delta along Middle River and Victoria Canal to the export pumps in the south Delta. The plan includes the pre-positioning of emergency construction materials at existing and new stockpiles and warehouse sites in the Delta, and development of tactical modeling tools (DWR Emergency Response Tool) to predict levee repair logistics, water quality conditions, and timelines of levee repair and suitable water quality to restore exports. The Delta Flood Emergency Management Plan has been extensively coordinated with state, federal and local emergency response agencies.

DWR, in conjunction with local agencies, the Corps and Cal OES, regularly conduct simulated and field exercises to test and revise the plan under real time conditions.

DWR and the Corps provide vital Delta region response to flood and earthquake emergencies, complementary to an overall Cal OES structure. Cal OES is preparing its Northern California Catastrophic Flood Response Plan that incorporates the DWR Delta Flood Emergency Management Plan. These agencies utilize a unified command structure and response and

recovery framework. DWR and the Corps, through a Delta Emergency Operations Integration Plan, would integrate personnel and resources during emergency operations.

Levee Improvements and Prioritization. The DWR Delta Levees Subvention Program has prioritized, funded, and implemented levee improvements along the emergency freshwater pathway and other water supply corridors in the central and south Delta region. These efforts have been complementary to the DWR Delta Flood Emergency Management Plan, which along with use of pre-positioned emergency flood fight materials in the Delta, relies on pathway and other levees providing reasonable seismic performance to facilitate restoration of the freshwater pathway after a severe earthquake. Together, these two DWR programs have been successful in implementing a coordinated strategy of emergency preparedness for the benefit of SWP and CVP export systems. Moreover, levee improvements along the pathway and Old River levees consisting of crest raising, crest widening, landside slope fill and toe berms meet the needs of local reclamation districts and substantially improve seismic stability to reduce levee slumping and create a more robust flood-fighting platform.

Many urban water supply agencies have participated or are currently participating in levee improvement projects along the Old and Middle River corridors.

Scenario 2: Complete Disruption of the California Aqueduct in the San Joaquin Valley
The 1995 flood event at Arroyo Pasajero demonstrated vulnerabilities of the California Aqueduct (the portion that traverses the San Joaquin Valley from San Luis Reservoir to Edmonston Pumping Plant). Should a similar flood event or an earthquake damage this portion of the California Aqueduct, deliveries from San Luis Reservoir could be interrupted.

DWR has informed the SWP contractors that a four-month outage could be expected in such an event. MWA’s assumption is a six-month outage.

Arroyo Pasajero is located downstream of San Luis Reservoir and upstream of the primary groundwater banking programs in the San Joaquin Valley. Assuming an outage at a location near Arroyo Pasajero that resulted in the California Aqueduct being out of service for six months, supplies from San Luis Reservoir would not be available to those SWP contractors located downstream of that point. This would include MWA.

Scenario 3: Complete Disruption of the East Branch of the California Aqueduct
The East Branch of the California Aqueduct begins at a bifurcation of the California Aqueduct south of Edmonston Pumping Plant, which pumps SWP water through and across the Tehachapi Mountains. From the point of bifurcation, the East Branch is an open canal. If a major earthquake (e.g., an event similar to or greater than the 1994 Northridge Earthquake)

were to damage a portion of the East Branch, deliveries could be interrupted. The exact location of such damage along the East Branch would be key to determining emergency operations by DWR and the East Branch SWP contractors. Specifically, MWA’s six turnouts on the system could all be differently impacted, and some potentially not impacted at all. For this scenario, it was assumed that the East Branch would suffer a single-location break and deliveries of SWP water from north of the Tehachapi Mountains or of contractor water stored in groundwater banking programs in the San Joaquin Valley would not be available. It was also assumed that Silverwood and Perris dams would not be damaged by the event and that water in Silverwood and Perris Lakes would be available to the East Branch SWP contractors.

In any of these three SWP emergency outage scenarios, DWR and the SWP contractors would coordinate operations to minimize supply disruptions. Depending on the particular scenario or outage location, some or all of the SWP contractors south of the Delta might be affected.

But even among those contractors, potential impacts would differ given each contractor’s specific mix of other supplies and available storage. During past SWP outages, the SWP contractors have worked cooperatively to minimize supply impacts among all contractors.

Past examples of such cooperation have included certain SWP contractors agreeing to rely more heavily on alternate supplies, allowing more of the outage-limited SWP supply to be delivered to other contractors, and exchanges among SWP contractors, allowing delivery of one contractor’s SWP supply or other water to another contractor, with that water being returned after the outage was over.

Of these three SWP outage scenarios, the scenario of an East Branch outage along with no delivery of stored water from Silverwood Lake presents the worst-case scenario for MWA. In this scenario, MWA and retail agencies would continue to rely solely on local managed groundwater supplies (native water, natural recharge, return flow, and stored imported water).

Seismic Risk Assessment and Hazard Mitigation Plan
Beginning January 2020, CWC Section 10632.5 mandates urban water suppliers include in their UWMP a seismic risk assessment and mitigation plan to assess the vulnerability of each of the various facilities of a water system and mitigate those vulnerabilities. This requirement can be met by submittal of a copy of the most recent adopted local hazard mitigation plan (LHMP) or multi-hazard mitigation plan under the federal Disaster Mitigation Act of 2000 (Public Law 106-390) if the local hazard mitigation plan or multi-hazard mitigation plan addresses seismic risk. MWA has submitted a copy of the San Bernardino County Multi-

Jurisdictional Hazard Mitigation Plan, approved by the Federal Emergency Management Agency (FEMA) on December 3, 2022 (HMP).5
The fundamental hazards identified in this plan include Earthquake, Wildfire, Flood, Drought, Terrorism and Climate Change. The HMP addresses the vulnerabilities associated with these items, the other plans and financial issues that impact implementation of the HMP, as well as a comprehensive mitigation strategy. Accordingly, the HMP is incorporated by reference into MWA’s WSCP.

1.4. Communication Protocols
MWA will engage in specific communication protocols in developing and implementing the WSCP and coordinate with the Regional Water Purveyors and neighboring public agencies to communicate water shortage conditions. MWA will seek to engage customers and provide notice with locally relevant actions that further the water shortage response actions. These actions may include:
• Publishing information on MWA’s website.
• Establishing a telephone hotline.
• Coordinating through direct correspondence with local agencies on water supply management
• Preparing social media posts to communicate MWA actions. • Advertising actions on other local audio and video media. • Coordinating voluntary and mandatory water shortage condition activities with other local agencies.

Taken together, these communication actions will result in a more effective implementation of MWA’s WSCP.

1.5 Legal Authorities
MWA is empowered to implement and enforce its water shortage response actions specified in this section through the following legal authorities: California Water Code Water Appendix, Chapter 97, the Mojave Basin Area Adjudication, and the Warren Valley Judgment. MWA has authorities to manage water supplies in its service area, including management of SWP supplies and R
3 facilities. MWA’s role as Watermaster under the Mojave Basin Area Adjudication empower it with the authorities to address excessive water use among 5 https://oes.sbcounty.gov/wp-content/uploads/sites/110/2024/06/HMP-2022.pdf

participating agencies. The Warren Valley Judgment addresses unauthorized or excessive use issues among the participating agencies. However, MWA does not have direct authority to limit groundwater pumping within its service area.

1.6 Financial Consequences of WSCP
MWA has assessed the financial conditions associated with developing and delivering water supplies within its service area boundary. As shown in Chapter 4, MWA has developed alternative water supplies that can be accessed to continue water deliveries during extended dry conditions. Accordingly, although MWA may experience minor financial fluctuations due to water shortage conditions, the redundancy in its water storage systems as well as its coordinated approach to managing dry conditions with the retail agencies will insulate MWA from significant financial consequences. Therefore, this WSCP does not anticipate that implementation of MWA’s WSCP will create financial conditions that are detrimental to MWA.

1.7 Re- evaluation and Improvement Procedures
MWA will continually review and assess its procedures for implementing the WSCP.

Specifically, MWA will use the monitoring and reporting protocols identified above as a quality assurance and quality control measure to understand the effectiveness of water shortage activities. These re-evaluation and improvement procedures will include developing reports, memoranda, and presentations that assess the effectiveness of water shortage actions and the WSCP. These protocols will be continually assessed and updated by MWA management staff.

1.8 Special Water Feature Distinction
MWA’s water shortage response actions focus on health and safety issues and working with retail agencies to manage available supplies. MWA will work with the retail agencies on communicating and implementing those agencies’ special water feature distinction issues that may arise during critical water shortage conditions.

1.9 Plan Adoption, Submittal, and Availability
The WSCP has been adopted, submitted, and is available as required by the Urban Water Management Planning Act. As a stand-alone document, the WSCP is also subject to separate adoption, submittal, and availability processes, and whenever it is separately amended or revised in the future. MWA has followed all applicable law in adopting the WSCPs. The current adopted WSCP for the shall be available to its customers and to the to all

local agencies in Mojave Water Agency’s service area within San Bernardino County no less than 30 days before its adoption. A copy of the current WSCP is available for public inspection during business hours at www.mojavewater.org and is available for download at www.mojavewater.org/planning.html
.

APPENDIX 7A- HESPERIA WATER

DISTRICT WSCP

Hesperia Water District
Water Shortage Contingency Plan

Water Shortage Contingency Plan
This Water Shortage Contingency Plan (WSCP) addresses the requirements in Water Code Section 10632 of the Urban Water Management Planning Act (The Act). The WSCP is incorporated into the 2025 Urban Water Management Plan (UWMP) and is used by the Hesperia Water District (Hesperia or District) to respond to water shortage contingencies as they may arise. The WSCP addresses possible conditions in which the water supply available to customers of the District is insufficient to meet the normally expected customer water use at a given point in time due to drought, regulatory action constraints, and natural and man-made disasters. This WSCP describes the Hesperia’s strategy for allocating water during such water supply shortages, while assuring customers that at all times it will meet the minimum health and safety requirements of a drinking water purveyor.

This WSCP consists of the following required elements:

1. An analysis of water supply reliability.

2. Procedures for conducting an annual water supply and demand assessment.

3. Six standard water shortage levels corresponding to progressive ranges of up to 10, 20, 30, 40, and 50 percent shortages and greater than 50 percent shortage.

4. Shortage response actions that align with the defined shortage levels.

5. Communication protocols and procedures.

6. Customer compliance, enforcement, appeal, and exemption procedures.

7. A description of legal authorities.

8. A description of financial consequences.

9. Monitoring and reporting requirements.

10. Reevaluation and improvement procedures.

11. Special Water Feature Distinction.

12. Plan Adoption, Submittal, and Availability.

The Act contains specific requirements for each of these elements.1 As required by Water Code Section 10632 this WSCP is incorporated into the UWMP, yet it is also a stand-alone plan that is adopted independently from the UWMP and may be amended or refined and readopted over coming months and years as needed (see subsection 1.12 Plan Adoption, Submittal, and Availability, below). Hesperia has enacted Chapter 14.04.170 of the Hesperia Municipal Code to address water shortages. 2 These local rules were developed to help manage water shortage conditions in the event of drought, catastrophic outage, or regulatory mandate requiring statewide reduction in water use. This WSCP is fully integrated with the District’s most recent Municipal Code Chapter 14.04.170.

1.1 Water Supply Reliability Analysis
The Hesperia Water District is a public agency created under the County Water District Act (Water Code Sections 30000 et seq.) providing water service to residential, commercial, industrial and institutional water users within the boundaries of the District. The Hesperia Water District was established as a subsidiary district of the City of Hesperia in 1990. The District operates a self -s
ustaining utility business
enterprise and the City Council serves as the District’s Board of Directors. The District is located in the High Desert region of San Bernardino County and is bordered by the Town of Apple Valley to the northeast, the City of Victorville to the north, and the unincorporated community of Phelan to the west.

The area south of the Hesperia includes the unincorporated community of Oak Hills and currently undeveloped lands. The District delivers quality, reliable water to over 29,000 active service connections serving a population of approximately 120,530 within a service area of 74 square miles that closely approximates the City of Hesperia’s boundaries, with minor exceptions as shown in Figure 1-1.

Figure
1-1: Hesperia’s Service Area

1 California Water Code Section 10632, available at:
(https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=WAT&sectionNum=10632) 2 Hesperia Municipal Code Chapter 14.04.170 Water Conservation and Water Shortage Plan.

As described in Sub-chapter 11.5 of the UWMP, the District has a reliable water supply in normal, single dry and five consecutive dry years through 2050. Hesperia relies on managed groundwater water that is pumped from the Mojave River Groundwater Basin (basin) with supplemental supplies derived from MWA imported water, return flows, and replacement and make-up supplies. Water is conveyed from the wells to Hesperia consumers via a distribution system with pipe sizes ranging between 4 and 24 inches in diameter. The District currently maintains 14 storage reservoirs within the distribution system with a total capacity of nearly 200 AF, or 64 million gallons.

Gr
oundwater is subject to management in compliance with a groundwater adjudication, the Mojave Basin Area Judgment (Judgment). Imported water is used to recharge the groundwater basin and offset pumping, such that water levels in the basin have generally remained stable under the Judgment. The groundwater supply is anticipated to remain reliable because the long -ter
m average of the groundwater
basin includes dry periods, and any single or multiple-yea r dry cycle does not impact the long-ter
m yield
of the basin. The District’s water supply sources may be impacted by climate factors, catastrophic events, and regulatory measures – all of which are considered in the reliability assessment in Sub- chapter 11.5. The District regularly evaluates its overall water supply reliability through its Urban Water Management Plan and through regional planning efforts in coordination with MWA and other neighboring water purveyors.

Al
though the District has a secure water supply, this WSCP serves as a roadmap to help the District meet the challenges that may arise from future droughts, regulatory actions, and unforeseen man-made and natural disasters.

1.2 Annual Water Supply and Demand Assessment Procedures The WSCP describes the District’s procedural methodology for managing shortages and conducting its required Annual Water Supply and Demand Assessment (Annual Assessment). The Annual Assessment is to be submitted to California Department of Water Resources (DWR) by July 1 each year with the first Annual Assessment due July 1, 2022. The Annual Assessment examines Hesperia’s anticipated water reliability for the current year and one additional dry year. The Annual Assessment will be prepared at the beginning of each calendar year to evaluate near-term water supply reliability and determine what, if any, water shortages stages may be triggered during the required period. The Annual Assessment will be used by Hesperia decision-makers to prepare for and initiate implementation of any needed response actions, as well as to inform customers, the general public, interested parties, and local, regional, and state governmental entities to prepare for such required actions.

1.2.1 Analytical and Decision-making Processes
Hesperia plans to conduct its Annual Assessment according to the following timeline and process:

By February 1 Initial data collection and analysis
By March 1 Preliminary Draft Annual Assessment internal review and revisions By April 1 Draft Annual Assessment and results briefing for Hesperia decision-makers

By May 1 Public Notification and Release of Draft Annual Assessment By June 1 Approval of Annual Assessment by Hesperia decision-makers By June 15 Submit Annual Assessment to DWR in advance of July 1 deadline The District will prepare its Annual Assessment using the following key data and analytical procedures (which may be modified as needed):
 Prepare supply estimates for each water source on a monthly basis for the analysis period.  Update unconstrained customer demand and estimate anticipated actual water use on a monthly basis for the analysis period.
 Update infrastructure assessment, including estimated water supply production capability on a monthly basis for the analysis period.
 Identify and quantify any locally applicable factors that may influence or disrupt supplies during the analysis period.
 Refine the definition of “dry year” as relevant to dry conditions like water year 2015 and 2021.  Identify any shortfall between projected supply and anticipated demand.  Identify and incorporate any applicable constraints (infrastructure, regulatory, etc.).  Develop, analyze, and propose water resource management strategies to address any shortfall between projected supply and anticipated demand with reference to the water shortage stages identified in this WSCP.
 Present the Annual Assessment (and resulting water shortage stage declaration, if applicable) to the District decision-makers.

If the results of the Annual Assessment indicate the need for any alternative water shortage response actions which may be addition to those specified in Section 1.4, below, the alternative response actions will be described and submitted in the Annual Assessment, as specified in CWC 10632.2.

1.2.2 Submittal Procedure
The District will submit its Annual Assessment to the DWR via email by June 15 each year, but in no case later than July 1 each year. At the time of DWR submittal, Hesperia will also notify the MWA, the City of Victorville, the Town of Apple Valley, San Bernardino County, the public, and other stakeholders concerning the results of the Annual Assessment and where it is available for review.

1.3 Six Standard Water Shortage Stages and Triggers
New state requirements for the WSCP require water suppliers to adopt six water shortage stages, which correspond to progressively severe water shortage conditions (up to 10%, 20%, 30%, 40%, 50%, and greater than 50% percent shortage), as compared to the normal service reliability condition. The District has adopted the six standard water shortage stages as shown in Tables 1-1 through -6 that are included in Section 14.04.170 of the Municipal Code. Each stage corresponds to a range of reduction in anticipated water supply availability and is aligned with shortage response actions which can reduce water demand as needed to address the water shortage. Reduction of available water supply by the

indicated percentages will trigger an appropriate water shortage stage and the District will implement the response actions identified in Tables 6-1 through 6-6.

1.4 Shortage Response Actions
The WSCP is required to identify locally appropriate shortage response actions that align with the defined shortage stages and include demand reduction actions, supply augmentation actions, system operational changes, and mandatory prohibitions against specific water use practices that are in addition to state-mandated prohibitions and appropriate to the local conditions. For each response action the WSCP is to provide an estimate of the extent to which the gap between supplies and demand will be reduced by implementation of the action.

1.4.1 Stages of Shortage Response Actions
The District has identified shortage response actions to be implemented during each of the six sequential stages and corresponding water shortage conditions. These actions are based on specific hydrological and regulatory conditions and the fundamental need to meet water service requirements within the District’s service area. Moreover, the shortage response actions provide the District with some flexibility to address water dynamic water shortage conditions while protecting the District against extreme conditions where supplies are drastically reduced beyond 50%. The following is an overview of the staged response actions the District could follow during a given water shortage condition based on shortage severity, relative supply conditions for each stage, and percent shortage reduction levels. A water shortage declaration would be made by resolution of the Board of Directors, with administrative discretion delegated to the General Manager.

The shortage response actions derived from Municipal Code Chapter 14.04.170 that may be implemented in each stage include, but are not limited to, the following:

Stage 1 (up to 10 percent shortage) “Water Alert” – If water supplies are threatened with constraint, the Plan calls for an introductory Stage 1 drought response, during which customers are informed of possible shortages and asked to voluntarily conserve 10 percent. In addition, customers are prohibited from wasting water or unreasonably using water for beneficial purposes. For example, prohibited water uses under this stage include allowing water to run off unused into a gutter, ditch, or drain; failing to repair a controllable leak; washing sidewalks, driveways, parking areas, tennis courts, patios, or other paved or areas; utilizing a hand-held hose without an automatic shut-off nozzle; and irrigating during a precipitation event. Additional prohibitions will apply to new developments prohibiting single pass- through cooling water systems; commercial car washes and laundries without recirculating water systems; and decorative fountains without recirculating water systems.

This stage includes performing public outreach and education about the shortage and methods individuals can implement to reduce their water use. The District will inform the public and neighboring governmental bodies of the potential shortage condition and will coordinate with customers to implement the actions consistent with this Stage.

Stage 2 (11 - 20 percent shortage) “Water Warning” – In the event Stage 2 is implemented the District will continue to encourage community-oriented voluntary conservation measures, enforce conservation measures, and implement mandatory water use reduction measures to decrease demand by up to 20 percent. Stage 2 activities include a continuation of activities described under Stage 1, as well as greater conservation and water use restrictions. These additional restrictions include beyond those identified in Stage 1, limiting outdoor irrigation only between the hours of 10:00 PM and 5:00 AM and vehicle washing must be done using a bucket or hand-held hose with an automatic shut-off nozzle, or take place at a commercial car wash. Customer baseline water use will be monitored and addressed with excess use above the shortage percentage subject to financial penalties under Ordinance 14.04.170.090.

The District will also continue to engage in public outreach and education as it applies to the water shortage conditions and the actions necessary to achieve up to 20% reduction in use.

Stage 3 (21 - 30 percent shortage) “Severe Shortage” – Stage 3 includes all response actions taken in Stages 1 and 2 and is focused on continuing to encourage customers to voluntarily reduce water use regarding turf watering, fillings pools, etc., mandatory-watering restrictions will be implemented following additional shortage actions described in Stage 2. Increased monitoring related to prescribed water conservation actions will occur under this stage. Customer baseline water use will be monitored and addressed with excess use above the shortage percentage subject to financial penalties under Ordinance 14.04.170.090.

The District will also continue to engage in public outreach and education as it applies to the water shortage conditions and the actions necessary to achieve up to 30% reduction in use.

Stage 4 (31 - 40 percent shortage) “Critical Shortage” – Stage 4 includes all response actions taken in prior stages regarding mandatory conservation and intensifies their implementation and enforcement.

Stage 4 restrictions will be implemented if the Stage 3 demand reduction and other response actions are deemed insufficient to achieve reductions due to water supply shortages. All Stage 3 response actions will be intensified, and water production will be monitored daily by Hesperia for compliance with necessary reductions. Customer baseline water use will be monitored and addressed with excess use above the shortage percentage subject to financial penalties under Ordinance 14.04.170.090.

The District will also continue to engage in public outreach and education as it applies to the water shortage conditions and the actions necessary to achieve up to 40% reduction in use.

Stage 5 (41 - 50 percent shortage) “Water Crisis” – Stage 5 includes all response actions taken in prior stages regarding mandatory conservation. The primary focus of Stage 5 is to ensure the protection of the water supply for all public health and safety purposes. This Stage will require reductions in water demand by up to 50 percent and will follow all voluntary and mandatory actions described in Stages 1-4.

Customer baseline water use will be monitored and addressed with excess use above the shortage percentage subject to financial penalties under Ordinance 14.04.170.090.

The District will also continue to engage in public outreach and education as it applies to the water shortage conditions and the actions necessary to achieve up to 50% reduction in use.

Stage 6 (greater than 50 percent shortage) “Water Emergency” – Stage 6 includes all response actions taken in prior stages focused on reducing water demands by more than a fifty percent in response to greater than 50 percent water shortages. This water emergency stage actions become effective when the Board of Directors declares that the District is unable to provide sufficient water supply to meet ordinary demands, to the extent that insufficient supplies are available for human consumption, sanitation, and fire protection. The declaration is to be based on their judgment concerning the degree of the immediate or future supply deficiency. This stage requires only use of water for human health and safety purposes. No additional water uses are permitted, including any outdoor irrigation for anything other than maintenance of legacy vegetation. Customer baseline water use will be monitored and addressed with excess use above the shortage percentage subject to financial penalties under Ordinance 14.04.170.090.

The District will also continue to engage in public outreach and education as it applies to the water shortage conditions and the actions necessary to achieve greater than 50% reduction in use. Tables 6-1 through 6-6 show a summary of the staged response actions.

Table 1-1: WSCP Actions to Reduce Customer Use - Stage 1 Stage 1 Water Alert: Savings up to 10%

1. Waste and unreasonable use of water prohibited and voluntary conservation encouraged (up to 10%).

2. Water shortage situation and possible subsequent water shortage stages explained to the public and governmental bodies (up to 10%)

3. Establish customer use baselines.

4. Identify customers with high per capita water usage to achieve proportionally greater reduction than those with low use.

5. Water use penalties under 14.04.160 available.

6. Actions may include, but are not limited to: Public information campaign consisting of distribution of literature, speaking engagements, website updates, bill inserts, and conversation messages printed in local newspapers and educational programs in area schools.

7. Consumption Reduction Methods, including:
• Encourage customers to fix leaks or faulty sprinklers promptly (0-1%). • Decorative water features (water fountains, etc.) to recirculate water and be leak proof (0-1%). • Direct customers to irrigate landscapes during cooler morning and evening hours to reduce evaporation and minimize landscape runoff (0-5%).
• Landscape watering shall be confined to a user's property and shall not runoff onto adjacent properties, roadsides or gutters (0-5%).
• No landscape watering shall occur while it is raining (0-5%). • Use a shutoff nozzle on hoses (0-1%).
• Washing down impervious surfaces such as driveways and sidewalks is prohibited unless for public health and safety purposes (0-1%).
• Unauthorized use of hydrants is prohibited. Authorization for use must be obtained from water supplier (0-1%).
• Commercial, industrial, institutional equipment must be properly maintained and in full working order (0-1%).
• Encourage customers to wash only full loads when washing dishes or clothes (0-1%). • Encourage customers to use pool covers to minimize evaporation (0-1%). • Encourage restaurants to only serve water to customers on request (0-1%).

Table 1-2: WSCP Actions to Reduce Customer Use – Stage 2 Stage 2 Moderate Shortage: Savings up to 20%

1. All measures implemented in Stage 1

2. Voluntary conservation usage reductions (up to 20%)

3. Mandatory conservation rules and restrictions and some prohibitions on end uses (10-20%).

4. Water Use Penalties under 14.04.160 available.

5. All consumption reduction methods from Stage 1 and intensified as needed; additionally:
• Mandatory outdoor irrigation restrictions including limiting number of watering to 3 days per week, and time when irrigation can occur (e.g., between 9:00 pm and 9:00 am). Plant containers, trees, shrubs and vegetable gardens may be watered additional days using only drip irrigation or hand watering (5-10%).
• Fix leaks or faulty sprinklers within 7 days (0-1%).
• Restaurants serve water only upon customer request (up to 1%). • Pool covers required (up to 5%)
• Non-essential potable water uses strongly discouraged (up to 20%) • No restrictions on landscape watering with non-potable water. • Assess customer usage against baseline (up to 20%).

Table 1-3: WSCP Actions to Reduce Customer Use - Stage 3 Stage 3 Severe Shortage: Savings up to 30%

1. All measures implemented in Stages 1 and 2

2. Some or all of the following:
• Adherence to customer baselines and actual water use reductions water allocations and mandatory conservation rules (20-30%)
• Customer water usage in excess of baseline to be monitored and recorded • Water use prohibitions include further restrictions of days and daytime hours for watering, excessive watering resulting in gutter flooding, using a hose without a positive shutoff device, prohibition on use of decorative fountains with non-recirculating pumps, prohibition on washing down sidewalks or patios, not repairing leaks in a timely manner, etc. (up to 30%)

3. All activities are intensified and production is monitored daily for compliance with necessary reductions from customer baseline (up to 30%)

4. Water Use Penalties under 14.04.160 available

5. All Consumption Reduction Methods from Stage 2 and intensified as needed; additionally:
• Fix leaks or faulty sprinklers within 3 days (0-1%).
• Decorative water features that use potable water must be drained and kept dry (0-1%). • Car washing is only permitted using a commercial carwash that recirculates water or by high pressure/low volume wash systems (0-1%).
• Require a construction water use plan be submitted to the water supplier that addresses how impacts to existing water users will be mitigated (such as dust control) (0-1%). • With the exception of landscapes watered with non-potable water, limit the installation of new landscaping to drought tolerant trees, shrubs and groundcover. Prohibit installation of new turf or hydroseed. Customers may apply for a waiver to irrigate during an establishment period for the installation of new turf or hydroseed. (0-1%) • During Warm/Dry Season: Up to two days per week turf watering when using potable water (5-20%) and irrigation between 10 pm and 7 am. Cool/Wet Season: Turf shall not be watered unless utilizing non-potable water during extended dry spells (1-5%). • Mandatory rationing as measured against customer baseline (up to 30%)

Table 1-4: WSCP Actions to Reduce Customer Use - Stage 4 Stage 4 Critical Shortage: Savings up to 40%

1. All measures implemented in Stages 1-3

2. All activities are intensified and production is monitored daily for compliance with necessary reductions from customer baseline. (up to 40%)

3. All Consumption Reduction Methods from Stage 3 and intensified as needed; additionally:
• Fix leaks or faulty sprinklers within 1 day (0-1%).
• Existing pools shall not be emptied and refilled using potable water unless required for public health and safety purposes (0-1%).
• Water use for new landscape installations or renovations is not authorized (0-1%). • Previous waivers for watering during an establishment period will be revoked (0-1%). • Warm/Dry Season outdoor irrigation: Up to one day per week turf watering when using potable water (10-30%) from 11 pm to 6 am. Cool/Wet Season: Turf shall not be watered unless utilizing non-potable water during extended dry spells (1-5%).

4. Water use penalties under 14.04.160 available.

Table 1-5: WSCP Actions to Reduce Customer Use - Stage 5 Stage 5 Shortage Crisis: Savings up to 50%

1. All measures implemented in Stages 1-4

2. Source of supply for the System is severely curtailed to the level that requires each customer to restrict their water use for only human health and safety purposes (up to 50%)

3. All activities are intensified and production is monitored daily for compliance with necessary reductions from customer baseline (up to 50%).

4. All Consumption Reduction Methods from previous stages and intensified as needed

5. Update current water shortage condition response measures based on Board approvals and direction, state policy directives, emergency conditions, or to improve customer response

6. Water use penalties under 14.04.160 available.

7. Catastrophic Event (Supply reduction up to 50%): Implement Applicable Actions for Catastrophic Events (such as boil water order)

Table 1-6: WSCP Actions to Reduce Customer Use - Stage 6 Stage 6 Emergency Shortage: Savings greater than 50%

1. All measures implemented in Stages 1-5

2. Source of supply for the System is severely curtailed to the level that requires each customer to restrict their water use for only human health and safety purposes. Customer rationing may be implemented. (>50%)

3. All activities are intensified and production is monitored continually for compliance with necessary reductions from customer baseline (more than 50%).

4. All Consumption Reduction Methods from previous stages and intensified as needed

5. Update current water shortage condition response measures based on Board approvals and direction, state policy directives, emergency conditions, or to improve customer response

6. Catastrophic Event (Supply reduction greater than 50%): Implement Applicable Actions for Catastrophic Events.

7. Water use penalties under 14.04.160 available.

1.4.2 Demand Reduction Actions
The District has identified a range of available and feasible customer demand reduction actions that can be used adaptively and implemented with progressively greater intensity to meet the supply shortage challenges faced under each water shortage condition. These demand reduction actions are identified by the associated water shortage stage in which they may be implemented. Other response actions not specified in this Plan may also be identified by the District to implement the essential purposes of this Plan or the UWMP (see CWC 10632.2).

Tables 6-1 through 6-6 summarizes the Demand Reduction Actions associated with each water shortage stage and shortage level, provides an estimate of the action’s effectiveness as related to that stage.

1.4.3 Mandatory Prohibitions
This section is required to identify any mandatory prohibitions against specific water use practices that are in addition to state-mandated prohibitions and appropriate to the local conditions. Hesperia adopted an ordinance to prohibit water waste, Chapter 14.04.160 of the Municipal Code. The ordinance prohibits intentional or unintentional water waste and unreasonable uses of water and encourages beneficial water use.

Chapter 14.04.160 reads in its entirety:

A. Wasting Water. No customer shall unreasonably or wastefully use district’s water. Where water is unreasonably or wastefully used on a customer's premises, the district may fine the customer after giving the customer notice if such conditions are not immediately corrected. In the event the customer does not immediately correct the unreasonable or wasteful use of water identified in the notice, the district may continue to fine the customer or disconnect the customer’s service. Unreasonable or wasteful use of water is presumed where a customer is not in compliance with a water shortage plan under section 14.04.170. In the event the district assesses fines or disconnects water service, the

district shall not be liable to the customer or to any employee, licensee, invitee or permittee of the customer on account of any bodily injury or property damage alleged to have occurred on account of such action taken by the district.

B. Unreasonable and Wasteful Water Use – Remedial Actions. No customer or other person acting on behalf of or under the direction of a customer shall cause or permit the unreasonable or wasteful use of water. If the general manager of the district or his designee finds that any customer or other person is in violation of the provisions in this section, in addition to any other remedies available, any one or more of the following actions may be taken by the general manager:

1. Initiate a fine of no more than $100 per day for each day the unreasonable or wasteful water use violation is not remedied by the customer after giving prior written notice of potential fine if the violation is not immediately corrected. Notice may be by delivery to the customer or person appearing to be in charge on the premises, or by placing the notice on the door handle, gate, or other conspicuous place on or about the property receiving the water service and immediately mailing a copy of the notice to the customer at the last known mailing address in the district's customer records. Notice shall be given at least twenty-four (24) hours by the general manager or his designee before fine assessment unless the general manager, or his designee, in his discretion, determines that a shorter period of notice is required in view of the nature of the violation and to protect the public health and safety, in which case the notice shall be given as expeditiously as the general manager or his designee finds to be reasonable under the circumstances.

2. Disconnect water service either for unreasonable or wasteful water use (if separate meter and turnoff facilities are available for those purposes) or to the entire premises served, as deemed appropriate under the circumstances by the general manager, after giving prior written notice that service will be disconnected if the violation is not immediately corrected. Notice may be by delivery to the customer or person appearing to be in charge on the premises, or by placing the notice on the door handle, gate, or other conspicuous place on or about the property receiving the water service and immediately mailing a copy of the notice to the customer at the last known mailing address in the district's customer records. Notice shall be given at least twenty-four (24) hours by the general manager or his designee before disconnection unless the general manager, or his designee, in his discretion, determines that a shorter period of notice is required in view of the nature of the violation and to protect the public health and safety, in which case the notice shall be given as expeditiously as the general manager or his designee finds to be reasonable under the circumstances.

3. Request initiation of proceedings for prosecution by the district attorney or any other proper prosecuting officer of any violation of this section.

4. The customer may appeal the assessment of fines, termination of service, or initiation of prosecution by appearing before the district at a regularly scheduled board meeting.

Disconnection of service will be administered in compliance with then-applicable state regulations.

Certain prohibited activities are also listed among the demand reduction actions on Tables 1-1 through 1-6.

1.4.4 Emergency Operations Plan for Catastrophic Water Shortages This section identifies actions to be undertaken by Hesperia to prepare for, and implement during, a catastrophic interruption of water supplies. In addition to climate, other events that can cause water supply shortages are earthquakes, chemical spills, dam failures, canal breaks, waterline ruptures, and energy outages at treatment and pumping facilities, which could cause a water shortage severe enough to trigger a Stage 1-6 water supply shortage condition.

The District has an adopted an Emergency Operations Plan which provides procedures and guidance to District personnel in responding to emergency situations including catastrophic events, both natural and manmade. The plan provides procedures for preparing, mobilizing, and employing District resources and coordinating outside resources during an emergency. The District provides periodic training, including simulated events and responses to keep District personnel fully trained on implementation of emergency procedures. Mobilization is consistent with Standardized Emergency Management and the Incident Command System.

In addition to specific actions to be undertaken during a catastrophic event, Hesperia performs maintenance activities, such as annual inspections for earthquake safety, and budgets for emergency items, such as auxiliary generators, to prepare for potential events.

Table 1-7 is a summary of actions cross-referenced against specific catastrophes for three of the most common possible catastrophic events: regional power outage (such as Public Safety Power Shutoff or “PSPS” events), natural disasters (such as earthquake, flood or storm damage, or fire), and malevolent acts.

Table 1-7: Summary of Actions for Catastrophic Events
Possible
Catastrophe Summary of Potential Actions
Regional Power
Outage

1. Isolate areas that will take the longest to repair and/or present a public health threat.

Arrange to provide emergency water.

2. Establish water distribution points and ration water if necessary.

3. If water service is restricted, attempt to provide potable water tankers or bottled water to the area.

4. Make arrangements to conduct bacteriological tests, in order to determine possible contamination.

5. Utilize backup power supply to operate pumps in conjunction with elevated storage.

Natural Disaster 1. Assess the condition of the water supply system.

2. Complete the damage assessment checklist for reservoirs, water treatment plants, system transmission and distribution.

3. Coordinate with Governor’s Office of Emergency Services utilities group or fire District to identify immediate firefighting needs.

4. Isolate areas that will take the longest to repair and/or present a public health threat.

Arrange to provide emergency water.

5. Prepare report of findings, report assessed damages, advise as to materials of immediate need and identify priorities including hospitals, schools and other emergency operation centers.

6. Take actions to preserve storage.

7. Determine any health hazard of the water supply and issue any “Boil Water Order” or “Unsafe Water Alert” notification to the customers.

8. Cancel the order or alert information after completing comprehensive water quality testing.

9. Make arrangements to conduct bacteriological tests, in order to determine possible contamination.

Malevolent acts 1. Assess threat or actual intentional contamination of the water system.

2. Notify local law enforcement to investigate the validity of the threat.

3. Get notification from public health officials if potential water contamination

4. Determine any health hazard of the water supply and issue any “Boil Water Order” or “Unsafe Water Alert” notification to the customers, if necessary.

5. Assess any structural damage from an intentional act.

6. Isolate areas that will take the longest to repair and or present a public health threat.

7. Arrange to provide emergency water.

1.4.5 Seismic Risk Assessment and Mitigation Plan
Beginning January 2020, CWC Section 10632.5 mandates urban water suppliers include in their UWMP a seismic risk assessment and mitigation plan to assess the vulnerability of each of the various facilities of a water system and mitigate those vulnerabilities. This requirement can be met by submittal of a copy of the most recent adopted local hazard mitigation plan or multi-hazard mitigation plan under the federal Disaster Mitigation Act of 2000 (Public Law 106-390) if the local hazard mitigation plan or multi-hazard mitigation plan addresses seismic risk.

Hesperia intends to submit a copy of the San Bernardino County Multi-Jurisdictional Hazard Mitigation Plan, approved by the Federal Emergency Management Agency (FEMA) on July 13, 2017 (HMP). This Hazard Mitigation Plan is currently under review and may have updates before the next Urban Water Management Plan cycle in 2025.

The fundamental hazards identified in this plan include Earthquake, Wildfire, Flood, Drought, Terrorism and Climate Change. The HMP addresses the vulnerabilities associated with these items, the other plans and financial issues that impact implementation of the HMP, as well as a comprehensive mitigation strategy. Accordingly, the HMP is incorporated by reference into Hesperia’s WSCP.

1.5. Communication Protocols
The District maintains an established and effective communications program to inform its customers, neighbors, and other stakeholders of water service issues, updates, and policies. Implementation of the WSCP will utilize the existing communication program structure to inform customers and others of the declared shortage stage and respective actions and restrictions in place.

The District Board meetings addressing the Annual Assessment and any potential water shortage declaration will be noticed using normal Board meeting public notification procedures. The meeting will also be announced through regular press release protocols.

Once a shortage stage as been declared by the Board of Directors, the District will notify its customers and others through a range of efforts. The stage and restrictions will be identified in a press release, customer billing statements, and posted on the District’s website. Specifically, the District’s website will be updated to feature the shortage declaration, restrictions, and resources available to customers from the District and other entities to help meet the restrictions. Subsequent District Board meetings will include a review of the shortage condition, customer response results, and discussion and recommendations for potential modifications. The District will also coordinate with the neighboring public agencies to declare a local emergency with respect to anticipated water supplies and demands in the event conditions necessitate.

The District’s communications protocols may include, but are not limited to, some or all of the following locally relevant actions. These communications protocols will be used at the discretion of District staff based on then-current and anticipated water shortage conditions:
 Publishing information on Hesperia’s website.

 Staffing a telephone hotline.
 Providing bill inserts and direct mailings above and beyond those legally required.  Directly calling and/or emailing customers.
 Developing materials for non-English speaking customers.  Preparing social media posts to communicate Hesperia actions.  Advertising actions on other local audio and video media.  Coordinating voluntary and mandatory water conservation activities with other local and regional governing bodies.

1.6. Compliance and Enforcement
The District’s Emergency Water Conservation Plan has significant compliance and enforcement options for implementing its water shortage planning. Financial penalties, flow restrictors, and disconnected water service are among the options available to the District to ensure compliance with the required water shortage actions. Appeals processes are also available for those that are subject to the enforcement provisions of the Municipal Code.

The following civil actions can be initiated by the District:
 First violation. A written warning of the violation shall be issued to the respective water customer.
 Second violation. A $100 per day penalty will be imposed on the water customer.  Third violation. Potential Termination of Service
In addition, the General Provisions of the California Municipal Code states that the District may begin an administrative proceeding against the customer to impose and collect the administrative fine and recover the District’s enforcement costs, if a notice of public nuisance has been issued to the customer and corrective work specified in the notice has not been completed within specified time.

1.7. Legal Authorities
The District is empowered to implement and enforce its WSCP under its organizing statutes and Section

14.04.170 of the Municipal Code.

In addition, the District is able to exercise general powers granted to water distributors in CWC §§350- 359. CWC §350 authorizes the governing body of a distributor of a public water supply to declare a water shortage emergency whenever it finds and determines that the ordinary demands and requirements of water consumers cannot be satisfied without depleting the water supply of the distributor to the extent there would be insufficient water for human consumption, sanitation, and fire protection. Upon a finding of such an emergency condition, the distributor can adopt such regulations and restrictions on the delivery and consumption of water as will conserve the water supply for the greatest public benefit, with particular regard to domestic use, sanitation, and fire protection (CWC §353). The regulations and restrictions remain in force and effect until the supply of water available for distribution within such area has been replenished or augmented, and restrictions may include the right to deny new service connections and discontinue service for willful violations (CWC §355 and §356). The