Milpitas City Council
June 9, 2026

City of Milpitas 2025 Urban Water Management Plan DRAFT 13 There have been minor changes to the Water Code since the 2020 UWMP was submitted; primarily, several definitions have been added. However, UWMP requirements for 2025 remain the same. Updated guidance for the 2025 UWMP effort includes the following:
• Suppliers with Multiple P ublic Water Systems – More consistent criteria were provided to determine when a supplier with multiple Public Water Systems must submit a UWMP. • DWR Submittal Tables – Improvements were made for accuracy and clearer identification between required and optional data.
• Water Loss Standard Reporting – There has been no change to the Water Code regarding water loss standard reporting since 2020 UWMPs were submitted, except that Suppliers are now required to report progress toward meeting the 2028 Water Loss Standard.
• Direct Potable Reuse – The State Water Board has adopted regulations for the use of direct potable reuse since the 2020 UWMP was submitted. Minor updates were added to supply and demand tables to support clearer direct potable reuse reporting.
• Lower-Income Housing Demands – While projections for lower- income housing were required in the 2020 UWMP, additional guidance has been provided for optional reporting of the method used to project water use for this type of housing. This optional guidance incorporates Regional Housing Needs Allocation (RHNA) into projected land uses and water demands. • Reporting Groundwater Recharge and Water Storage – In previous years, the guidance for reporting water storage water did not differentiate between long -term (i.e., water placed into storage one year but extracted in a future year) and short-term storage (i.e., water placed into storage and extracted the same year). New clarification is provided to prevent short-term storage from being double-counted.

City of Milpitas 2025 Urban Water Management Plan DRAFT 14 2 PLAN PREPARATION
Lay Description
This chapter describes the basis of the development of the U WMP, the requirements for preparation, and the processes used, including efforts in notification, coordination and outreach, the regional planning involved, and the type of year and units of measure used.

2.1 Plan Preparation
Coordination and outreach are key elements in developing a useful and accurate UWMP. Notifying neighboring water suppliers strengthens a region’s ability to plan for drought and catastrophic events. For further information about this notification process, see Chapter 10 of this UWMP.

Coordination with city and county land use planning agencies can provide information on regional planning, demographics, and expected future development for determining future water use, supply , and reliability.

Notification to all interested parties and stakeholders allows those entities to provide information on aspects of the UWMP, help ing to create a more useful plan. It also lets these entities know about the different water management considerations that may affect their own decisions. Section 2.6 fur ther describes the City ’s outreach activities.

The City is an active member of the water community and coordinated with these agencies for this UWMP:
• Bay Area Water Supply & Conservation Agency (BAWSCA)
• Valley Water
• San Francisco Public Utilities Commission (SFPUC)
The City coordinated various water planning documents to support development of this UWMP:
• Water Master Plan – Evaluates historical and existing water demands to review and refine performance and planning criteria to evaluate the water system and facilities. • General Plan – Identifies the community’s vision for the future and provides a framework that will guide decisions on growth, development, and conservation of open space and resources in a manner that is consistent with the quality of life desired by the City's residents and businesses.

2.2 Basis for Plan Preparation
California Water Code Section 10617 defines an urban water supplier as “ a supplier, either publicly or privately owned, providing water for municipal purposes either directly or indirectly to more than 3,000 customers or supplying more than 3,000 acre-feet of water annually. An urban water supplier includes a supplier or contractor for water, regardless of the basis of right, which distributes or sells for ultimate resale to customers. This part applies only to water supplied from public water systems.” 5 In accordance with the California Water Code Section
10621, urban water suppliers are required to prepare a UWMP every five years , and a Supplier shall adopt UWMP within one year after it has become a Supplier.6
As per th e above definition, the City qualifies as an urban water supplier. The City has prepared this plan in compliance with state law and following the guidelines as outlined by DWR in its Urban Water Management

5 California State Legislature. (1983). Water Code Section 10617, amended 1996. https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=WAT&sectionNum=10617. 6 California State Legislature. (1983). Water Code Section 10621. http://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=WAT&sectionNum=10621

City of Milpitas 2025 Urban Water Management Plan DRAFT 15 Plan Guidebook 2025, posted as Final on January 29, 2026 (DWR, 2026). This 2025 UWMP is the five-year update and supersedes the contents of the 2020 UWMP.

Public water systems are the distribution systems that provide drinking water for human consumption. All public water systems are given a unique Public Water System Identification Number. These systems are regulated by the State Water Board, Division of Drinking Water. The California Health and Safety Code 116275 defines a public water system as “a system for the provision of water for human consumption through pipes or other constructed conveyances that has 15 or more service connections or regularly serve s at least 25 individuals daily at least 60 days out of the year.” 7 Based on this definition, the City of Milpitas is a Public Water System and therefore operates under a water supply permit issued by the Division of Drinking Water.

As indicated in Table 2-1, the City served 16,750 municipal connections and 3,238 million gallons (MG) of water in 2025. The total number of connections accounts for all billed water meters in the City, including recycled water and fire meters. The total number of connections does not account for the number of multifamily residential units served by master meters. Multifamily residential developments, such as apartment complexes, may use a single master meter to measure consumption for more than one dwelling unit.

Table 2-1. Public Water Systems
Submittal Table 2-1 Retail: Public Water Systems
Has there been a change in the number of affiliated Public Water Systems since the 2020 UWMP? No
Public Water System
Number
Public Water System
Name
Number of Municipal
Connections 2025
Volume of
Water Supplied
2025
(MG)
4310005 City of Milpitas 16,750 3,238
Total 16,750 3,238
NOTES: Number of connections include active and inactive accounts. Total volume includes potable and non-potable production and use.

2.3 Regional Planning
Regional planning can deliver mutually beneficial solutions to all agencies involved by reducing costs for the individual agency, assessing water resources at the appropriate geographic scale, and allowing for solutions that cross jurisdictional boundaries. Depending on the level of regional cooperation, other possible benefits can include the following:
• More reliable water supplies
• Increased regional self-reliance
• Improved water quality
• Better flood management
• Increased economic stability
• Restored and enhanced ecosystems
• Reduced conflict over resources

7 California State Legislature, Health and Safety Code Section 116275. https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=HSC&sectionNum=116275

City of Milpitas 2025 Urban Water Management Plan DRAFT 16 In support of regional UWMPs and regional water conservation targets, the UWMP portion of the Water Code provides mechanisms for participating in area- wide, regional, watershed, or basin- wide urban water management planning. The City participates in regional planning, namely through participation with the Bay Area Water Supply & Conservation Agency (BAWSCA). Collectively, BAWSCA's member agencies are comprised of 26 agencies represented by 24 cities and water districts and two private utilities that purchase water wholesale from the San Francisco regional water system. These entities provide water to over 1. 8 million residents and nearly 40,000 commercial, industrial and institutional (CII) accounts in Alameda, San Mateo, and Santa Clara Counties.

As an active member of BAWSCA, the City works in conjunction with BAWSCA and the other member agencies.

BAWSCA represents the collective interests of these wholesale water customers on all significant technical, financial, and policy matters related to the operation and improvement of SFPUC’s R egional Water System (RWS). This regional planning interaction allows for broader distribution of materials and information and reduced costs to the individual water suppliers through resource sharing. BAWSCA’s role in the development of the 2025 UWMP updates is to work with its member agencies and SFPUC to seek consistency among UWMP documents.

In 2009, SFPUC and BAWSCA members entered into a Water Supply Agreement (WSA), 8 a 25 -year contract
outlining the relationship between the two entities. A key component of the WSA is that it continued the “Supply Assurance,” a maximum supply of 184 million gallons per day (MGD) to be allocated among BAWSCA members, established by the WSA’s predecessor (the 1984 Settlement Agreement and Master Water Sales Contract).

Though the Supply Assurance can be reduced due to drought, maintenance, or emergencies, the WSA established the 184 MGD delivery ceiling in perpetuity. The City has an Individual Supply Guarantee (ISG) of

9.232 MGD from SFPUC. This Supply Assurance and the City's ISG are discussed in more detail in section 7.2.5.

Per the City’s contract with Valley Water, detailed in Milpitas’s Water Master Plan, potable water deliveries consist of State Water Project and Central Valley Project water only, with amounts based on an annual request the City submits every three years. In each of the three years after submitting the request, the City is obligated to purchase at least 95% of the maximum amount listed on the schedule. Every month, Valley Water guarantees the City can receive at least 15% of the annual delivery schedule.

2.4 Individual or Regional Plans
The City develop ed this UWMP to report solely on its distribution service area. The UWMP addresses all requirements of the Water Code as provided in th e UWMP Guidebook. The City has notified and coordinated with the appropriate regional agencies and constituents.

This 2025 UWMP, which is an individual UWMP (see Table 2-2), updates and replaces the City’s 2020 UWMP.

Table 2-2. Plan Identification Type
Submittal Table 2-2: Plan Identification
Select Type of Plan

Individual UWMP

8 Water Supply Agreement between the City and County of San Francisco and Wholesale Customers (July 2009). https://bawsca.org/uploads/userfiles/files/Plans%20and%20Reports/FINAL_WSA_with_Attachments.pdf

City of Milpitas 2025 Urban Water Management Plan DRAFT 17

2.4.1 Regional UWMP
Suppliers may choose to work with other agencies within a region, such as wholesaler(s), other retailers, an Integrated Regional Water Management group, or other regional agencies to develop a Regional Urban Water Management Plan (RUWMP) instead of an individual one. A RUWMP reports on the combined regional service area and must still address all the requirements of the Water Code Section. The City did not participate in a RUWMP.

2.5 Fiscal or Calendar Year and Units of Measure
Since the City reports on a calendar year rather than fiscal basis, it is required to include the water use and planning data for the entire calendar year of 2025, which is reflected in this UWMP. In addition, the City utilizes million gallons throughout this plan as the unit of measurement when reporting water volume.

Table 2-3 provides Supplier identification information, type of year reporting, and units of measure used by the City in this 2025 UWMP.

Table 2-3. Supplier Identification
Submittal Table 2-3: Supplier Identification
Type of Supplier (select one or both)
Supplier is a wholesale supplier
Supplier is a retail supplier
Fiscal or Calendar Year (select one)
UWMP Tables are in calendar years
UWMP Tables are in fiscal years
Units of measure used in UWMP
Unit MG

2.6 Coordination and Outreach
This section describes the coordination and outreach efforts of the City during preparation of the 2025 UWMP.

2.6.1 Wholesale and Retail Coordination
When a water Supplier relies upon a wholesale agency for its water supply, both are required to provide each other with information regarding projected water supply and demand. Retail agencies that receive water from one or more wholesalers must provide their wholesaler(s) with projected water demand from that source in five-year increments for 20 years, or as far as possible based on available data.

During the preparation of the 202 5 UWMP and WSCP, the City coordinated information regarding projected water supply and demand with its two potable water wholesalers, the San Francisco Public Utilities Commission (SFPUC) and Valley Water, as listed in Table 2-4. The City maintains one groundwater well for use in emergencies, but it is not used as a normal supply. More information about coordination and notification efforts is in Chapter

10. Table 2-4. Water Supplier Information Exchange
Submittal Table 2-4 Retail: Water Supplier Information Exchange - Water Code Section 10631(h) The retail Supplier has informed the following wholesale supplier(s) of projected water use in accordance with Water Code Section 10631(h).

Wholesale Water Supplier Name
San Francisco Public Utilities Commission
Valley Water (previously named Santa Clara Valley Water District)

City of Milpitas 2025 Urban Water Management Plan DRAFT 18 BAWSCA provides regional water reliability planning and conservation programming for the benefit of its 26 member agencies (collectively the “Wholesale Customers” or “BAWSCA Member Agencies”) that purchase wholesale water supplies from SFPUC. Collectively, the Wholesale Customers deliver water to over 1.8 million residents and nearly 40,000 CII accounts in Alameda, San Mateo, and Santa Clara Counties.

BAWSCA also represents the collective interests of the Wholesale Customers on all significant technical, financial, and policy matters related to the operation and improvement of SFPUC’s RWS.

2.6.2 Coordination with Other Agencies and the Community On February 11 , 2026, the City distributed notices of preparation and intent to update the UWMP to the following agencies through email:
• San Francisco Public Utilities Commission, the City’s wholesaler • Valley Water, the City’s wholesaler
• BAWSCA and the 26 other BAWSCA member agencies that share SFPUC as a common wholesale water source9
• Great Oaks Water Company
• Milpitas Chamber of Commerce
• Milpitas Unified School District
• Alameda County Water District, the City’s emergency intertie • San Jose Water, the City’s emergency intertie
In addition to the notice of intent to update its UWMP, the City of Milpitas notified surrounding cities, Santa Clara County, BAWSCA and its member agencies , and the general public more than 60 days in advance of the public hearing. With the exception of the general public, notification was provided by email. Notification to the general public was completed through a display advertisement in The Milpitas Post. Copies of the email notices can be found in Appendix B of this UWMP, while a copy of the display advertisement is in Appendix C.

The Draft 2025 UWMP was made available for public review online on the City’s website. 10 The City held a public
hearing on June 9, 2026, to receive comments on the Draft 2025 UWMP prior to its adoption by the City Council.

The plan was adopted on June 9 , 2026, at the regular City Council meeting . The final, adopted version was submitted to DWR and included any public comments received.

A copy of the Final 2025 UWMP was submitted to the following entities:
• California Department of Water Resources
• California State Library
• BAWSCA and its 26 member agencies
• SFPUC
• Valley Water

9 BAWSCA. Member Agency Profiles web page, accessed April 2026: https://bawsca.org/members/profiles 10 https://www.milpitas.gov/752/Urban-Water-Management-Plan • Santa Clara County
• Spring Valley Heights Association
• Milpitas Unified School District
• Milpitas Chamber of Commerce

City of Milpitas 2025 Urban Water Management Plan DRAFT 19

2.6.3 Notice to Cities and Counties
The California Water Code 10621(b) requires that agencies notify cities and counties to which they serve water that the 2025 UWMP is being updated and reviewed. The California Water Code specifies that this must be done at least 60 days prior to the public hearing. The City has complied with this requirement. Its notification to cities and counties is reported in Table 10-1 in Chapter 10 of this UWMP.

City of Milpitas 2025 Urban Water Management Plan DRAFT 20 3 SYSTEM DESCRIPTION
Lay Description
This chapter describes the City’s water system, service area, climate, projected population , and other factors affecting water management planning. Potential uncertainties, such as the impacts of climate change , are discussed.

3.1 General Description
The City of Milpitas is in Santa Clara County near the southern tip of the San Francisco Bay, 45 miles south of San Francisco. The City of Fremont borders Milpitas to the north and the City of San Jose borders Milpitas to the south and west. Most of Milpitas’ 14 square miles of land is situated between two major freeways (I nterstates 880 and 680). The City has approximately 10 square miles of valley floor to the west and four square miles of hillside areas to the east. Industrial and commercial areas are lo cated on the valley floor with residential areas on the valley floor and hillside. Parks and recreational open spaces are distributed throughout residential areas.

Since its inception in 1954, the City has experienced steady growth and development. At the time of incorporation, the City covered an area of 2.9 square miles with a population of 825. Rapid growth began with the Ford Motor Company assembly plant in 1955 and continued with the technology industry in the 1970s. Most of the valley floor is fairly new. Growth slowed as a result of the recession in 2008. However, in more recent years, the transformation of industrial areas into high-density housing has resumed. The City contains a strong complement of employment and retail uses as well as housing. Large sources of employment include manufacturing, the school district, and the Great Mall shopping center.

The City owns, operates, and maintains a potable water distribution system which consists of five turnouts, one emergency groundwater well, three emergency interties, five storage reservoirs, five pump stations, 17 pressure reducing valves, and approximately 194 miles of pipeline. The City also operates and maintains a recycled water system owned by the City of San Jose’s South Bay Water Recycling (SBWR) program.

3.2 Service Area Boundary
As shown in Figure 3-1, the City’s potable water supply system is divided into two distinct service areas, corresponding to the areas served by the City’s two wholesalers: SFPUC and Valley Water. Under normal operating conditions, the City does not blend water from SFPUC and Valley Water. However, the two sources of water can be interconnected to provide an emergency water supply, if needed.

The City of Milpitas Sphere of Influence (SOI) includes both incorporated and unincorporated areas within which Milpitas has primary responsibility for providing public facilities and services. In 1998, voters in the City of Milpitas established an Urban Growth Boundary (UGB) limiting development on the eastern hillside. The initiative was set to expire in 2018 but was extended by Measure I in 2016 and will expire in 2038 . The Urban Service Area Boundary is contiguous with the UGB, and the Urban Service Area restricts the extension of public services and infrastructure to new development within the City limit eastern areas.

City of Milpitas 2025 Urban Water Management Plan DRAFT 21 Figure 3-1 shows the City’s SOI, UGB and Urban Service Area. One exception to the UGB is the Spring Valley Heights community, which is located outside the UGB but is served by the City’s water distribution infrastructure.

Figure 3-1. Potable Water Service Area Map

Source: West Yost. (2020). City of Milpitas Water Master Plan.

City of Milpitas 2025 Urban Water Management Plan DRAFT 22 Figures 3-2 and 3-3 provide further details regarding the City’s water system and infrastructure. Since the City has not had any service area changes since the 2020 UWMP, no service area change figure has been included. The City does not serve any parcels outside its jurisdiction, and since the jurisdictional boundary mirrors the service area, no jurisdiction boundary map has been included. The City does not own or operate a Raw Water Distribution System, so no such map has been included. However, Valley Water has a Raw Water Transmission System, a map of which can be found in Valley Water’s 2025 UWMP (pending publication in 2026).

Figure 3-2. Public Water System(s)

Source: West Yost. (2020). City of Milpitas Water Master Plan.

City of Milpitas 2025 Urban Water Management Plan DRAFT 23 Figure 3-3. City of Milpitas Recycled Water Distribution System

Source: City of Milpitas, 2025.

3.3 Service Area Climate
The City’s Mediterranean climate is characterized by warm, dry summers and mild , wet winters. Annual precipitation in the region is about 17 inches, annual evapotranspiration (ETo) approximately 45 inches, and average temperature approximately 57 degrees Fahrenheit (°F), according to the closest active CIMIS (California Irrigation Management Information System) station in Union City (Station #171).11 CIMIS is a database provided by DWR that tracks local weather data. Union City is approximately 17 miles away from Milpitas, on the east side of the Bay Area’s South Bay. Figure 3-4 summarizes monthly averages from 2002 to 2025.

11 CIMIS Station #171, Union City: https://cimis.water.ca.gov/stations

City of Milpitas 2025 Urban Water Management Plan DRAFT 24 Figure 3-4. Climate Characteristics

3.3.1 Climate Change Impacts on Water Demands, Supplies and Reliability According to the National Academy of Sciences,12 climate change refers to any significant change in measures of climate (such as temperature, precipitation, or wind) lasting for an extended period (decades or longer). Climate change may result from:
• Natural factors, such as changes in the sun's intensity or slow changes in the Earth's orbit around the sun.
• Natural processes within the climate system (e.g., changes in ocean circulation). • Human activities that change the atmosphere's composition (e.g., through burning fossil fuels) and the land surface (e.g. deforestation, reforestation, urbanization, desertification, etc.).

Climate change has the potential to directly impact the City’s surface water supply and to indirectly impact groundwater supplies. The City is committed to adapting to climate change in a manner that protects water resources for maximum benefit while continuing to maintain a reliable, affordable, high quality water supply for the community.

Several potential effects of climate change have been identified by the scientific community, including reduced winter snowpack, more variable and extreme weather conditions, shorter winters , and increased evaporative demand. Additionally, climate change could affect water quality through increased flooding and erosion; greater concentration of contaminants, if any, in the water supply; and warmer water, which could lead to increased growth of algae and other aquatic plants. Rising sea level and increased flooding are also potential effects of climate change.

12 National Academies of Sciences, Engineering, and Medicine. (2019). Strategic Water Planning: Climate, Drought, and Urban Water Management. https://www.nationalacademies.org/our-work/strategic-water-planning-climate-drought- and-urban-water-management

City of Milpitas 2025 Urban Water Management Plan DRAFT 25 Changes in precipitation, temperature and atmospheric carbon dioxide affect crop ETo and net irrigation water requirements. Global climate model s have been used to project future climate change and impacts on crop water demands. Future conditions of warm-dry, warm-wet, hot-dry, hot-wet, and central tendency were used.

Three future periods for these five conditions were selected to project climate change effects and impacts, including the 2020s (2010-2039), 2050s (2040-2069) and 2080s (2070-2099). Santa Clara County is expected to see increasing temperatures, which could result in more extreme heat and drought events and increased demands. Future projections of precipitation are not as clear. Changes in precipitation timing and amounts could result in greater or lesser irrigation requirements to meet ETo demands.

Although there is consensus that climate change is occurring, and the effects of climate change are being observed, the timing and magnitude of climate change impacts remain uncertain. The City will mitigate climate change impacts with this uncertainty in mind through an adaptive management approach in cooperation with other regional stakeholders and neighboring water management agencies. Under adaptive management, key uncertainties will be identified and evaluated (e.g., April- July runoff as a percentage o f annual runoff, total runoff, average temperature and reference ETo), and strategies will be developed to address the related climate change impacts. As the actual impacts occur, the strategies will be prioritized, modified as needed , and implemented. SFPUC completed a Climate Action Plan in 2021, with a Water Supply addendum in 2023. 13 Additional Resources for Water Resources Planning for Climate Change Much work has been done at state and regional levels to evaluate the effects and impacts of climate change and to develop strategies to support future effective statewide, regional, and local water management.

The following resources provide supplementary information on water resources planning for climate change:
• Ackerly, D., Jones, A., Stacey, M., & Riordan, B. (2018). California’s Fourth Climate Change Assessment:

San Francisco Bay Area Summary Report. https://www.climateassessment.ca.gov/ • California Department of Water Resources (DWR). (2008). Managing an Uncertain Future: Climate Change Adaptation Strategies for California’s Water.
https://digitalcommons.csumb.edu/hornbeck_usa_3_d/63/
• California Department of Water Resources (DWR). (2010). Climate Change Characterization and Analysis in California Water Resources Planning Studies. https://cawaterlibrary.net/document/climate- change-characterization-and-analysis-in-california-water-resources-planning-studies-2/ • California Department of Water Resources (DWR). (2024). Climate Action Plan Phase 1: Greenhouse Gas Emissions Reduction Plan Update 2023. https://water.ca.gov/-/media/DWR-Website/Web- Pages/Programs/All-Programs/Climate-Change-Program/Climate-Action-Plan/Files/Exhibit-C-CAP- Phase-1-Update-2023.pdf
• California Department of Water Resources (DWR). (2025). State Water Project Adaptation Strategy. https://mavensnotebook.com/wp-content/uploads/2025/08/SWP-AdaptationStrategy_Final.pdf • California Department of Water Resources (DWR). (2026). California Water Plan 2028. https://water.ca.gov/-/media/DWR-Website/Web-Pages/Programs/California-Water- Plan/Docs/Update2028/CWP-2028-Fact-Sheet.pdf
• California Energy Commission (CEC). (2018). California’s Fourth Climate Change Assessment: Statewide Summary Report. https://www.energy.ca.gov/sites/default/files/2019-11/Statewide_Reports-SUM- CCCA4-2018-013_Statewide_Summary_Report_ADA.pdf

13 SFPUC Climate Action Plan: Water Supply Addendum . https://www.sfpuc.gov/about-us/news/san-francisco-releases- updated-climate-action-plan-new-chapter-focusing-water-supply

City of Milpitas 2025 Urban Water Management Plan DRAFT 26 • California Governor’s Office of Emergency Services. (2020). California Adaptation Planning Guide. https://www.caloes.ca.gov/wp-content/uploads/Hazard-Mitigation/Documents/CA-Adaptation- Planning-Guide-FINAL-June-2020-Accessible.pdf
• California Natural Resources Agency. (2012). California Climate Adaptation Planning Guide. https://resources.ca.gov/CNRALegacyFiles/docs/climate/01APG_Planning_for_Adaptive_Communities .pdf
• California Natural Resources Agency. (2024). California Climate Adaptation Strategy. https://www.climateresilience.ca.gov/
• CDM. (2011). Climate Change Handbook for Regional Water Planning. https://cawaterlibrary.net/wp- content/uploads/2017/06/Climate_Change_Handbook_Regional_Water_Planning.pdf • Intergovernmental Panel on Climate Change (IPCC). (2022). Sixth Assessment Report: Impacts, Adaptation and Vulnerability, Chapter 4: Water.
https://www.ipcc.ch/report/ar6/wg2/chapter/chapter-4/
• U.S. Bureau of Reclamation (USBR). (2015). West-Wide Climate Risk Assessments: Irrigation Demand and Reservoir Evaporation Projections (Technical Memorandum No. 86-68210-2014-01). https://www.usbr.gov/watersmart/baseline/docs/irrigationdemand/irrigationdemands.pdf • U.S. Geological Survey. (2025). Climate Change and Future Water Availability in the United States (Professional Paper 1894-E). https://pubs.usgs.gov/pp/1894/e/pp1894E.pdf • University of California, Berkeley. (2012). Climate Change and Integrated Regional Water Management in California: A Preliminary Assessment of Regional Perspectives. https://watershedscoalition.org/wp- content/uploads/2022/07/IRWM_CCReport_Final_June2012_EConrad_UCBerkeley.pdf

3.4 Service Area Population, Demographics and Socioeconomics Suppliers are required to report their current and projected service area populations in their UWMP. The Water Code does not require a specific methodology for projecting future populations, but it does require that the estimates of future population be ba sed upon data from state, regional, or local service agency population projections.

3.4.1 Service Area Population
The City of Milpitas estimates its historical and current service area population using the California Department of Finance’s (DOF) Population and Housing estimates for current service area population. In 2020, Milpitas’ service area population was 77,961. It is estimated that Milpitas’ service area population was 81,773 in 2025, an increase of 4.9%.

Projected population from 2030 and 2050 is based on the 2025 BAWSCA Regional Water Demand and Conservation Projections Report
14 (Demand Study), which is described further in Section 4.2.5 of this UWMP. It is anticipated that Milpitas’ overall service area population will increase. By 2050, the total population within Milpitas’ service area is expected to be 137,000, which represents a 2.7% annual growth rate compared to the 2025 population.

14 Demand Study:
https://bawsca.org/uploads/userfiles/files/2025%20BAWSCA%20Demand%20Study_Final%20Report%20%2B%20Appendi ces_submittal%281%29.pdf

City of Milpitas 2025 Urban Water Management Plan DRAFT 27 Table 3-1. Retail Population – Current and Projected
Submittal Table 3-1 Retail: Population - Current and Projected - Water Code Section 10631(a) Population Served 2025 2030 2035 2040 2045 2050(opt)
81,773 96,900 109,800 118,900 127,900 137,000
NOTES: 2025 actual population value is from the Department of Finance Table E-5 for the City of Milpitas. Future population projections were developed for the City as part of BAWSCA's 2025 Regional Water Demand and Conservation Projections Study and are based on population growth rates from the Association of Bay Area Governments and the Metropolitan Transportation Commission's Plan Bay Area 2050 Traffic Analysis Zone (TAZ) dataset. Projection values are rounded to the nearest 100.

The expected population growth will come from redevelopment of two central areas defined in the Milpitas Gateway-Main Street Specific Plan (MGSP) and Milpitas Metro Specific Plan (MMSP). The MGSP outlines planned growth of a mixed-use community that includes high-density, transit-oriented housing and a central community “gathering place,” while maintaining needed industrial, service, and commercial uses. The plan is long -range in nature, intended to guide development through the year 2030. Some land in the Gateway area is undeveloped but easily developed over the short-term, while other parcels may be developed over a longer time frame.

The MGSP designation provides for the current and future uses of the Gateway area of Milpitas, in accordance with the overall plan. The MGSP sets forth the types, locations, and intensities of land uses to be accommodated within the Gateway area. Its purpose is to create an economically viable main street -type development that serves as a cultural hub of the City. A variety of uses are allowed in this designation, including entertainment, retail, commercial, residential, civic, cultural, office , and high -density mixed use residential in a compact, walkable, and unique centralized setting. All new developments occurring within the MGSP designation are required to adhere to the development standards and guidelines established in the MGSP. These projections are subject to change as the MGSP is updated.

The MMSP outlines planned growth at the hub of the existing Santa Clara Valley Transportation Authority Light Rail station and the recently opened Bay Area Rapid Transit (BART) station near the City’s Great Mall shopping center. The plan calls for new residential and mixed -use developments. New residential neighborhoods will consist of mixed-use areas with commercial use on the ground floor and residential units above in high-density residential neighborhoods. Industrial areas will be transitioned to areas that support higher density mixed use.

The MMSP designation establishes a framework for a walkable, transit -oriented area with a mix of land uses, which encourages walking, biking , and transit use while reducing vehicle trips and vehicle miles traveled.

Development allowed within the MMSP area accommodates substantial growth, while minimizing impacts on local roadways and reducing urban sprawl at the periphery of the region. All new development occurring within the MMSP designation adheres to the developmen t standards and guidelines established in the MMSP . These projections are subject to change as the MMSP is updated.

3.4.2 Other Social, Economic and Demographic Factors15
It is recommended that Suppliers describe the social, economic, and demographic factors of their service areas since recent trends or shifts in these factors can affect water management and planning.

As of 2025, Milpitas has a population of 81,773, with a daytime population of 102,000. Daytime population reflects people commuting into or out of the city for work, shopping, entertainment, and other activities.

15 City of Milpitas. (2020). Economic Development Strategy and Implementation Actions Final Report , accessed June 2026:
https://www.milpitas.gov/DocumentCenter/View/3095/Economic-Development-Strategy-Implementation-Actions- PDF?bidId=

City of Milpitas 2025 Urban Water Management Plan DRAFT 28 Milpitas has 44 businesses employing 100 or more workers, with Cisco Systems, KLA Corporation, and Western Digital as the three largest employers. Other major employers include Amazon, Becton, Dickinson and Company, Flex Ltd., Headway Technologies, Inc., and Milpitas Unified School District. Over 25% of the city’s workforce is employed in professional, scientific, management, and administrative services , more than 23% in manufacturing, about 15% in education and health care, 8% in retail, and 6% in arts and entertainment.

As of 2025, Milpitas has roughly 15.5 million square feet of office, research and development, and manufacturing space, along with 6.5 million square feet of warehouse and distribution space. This inventory is diverse and flexible, accommodating a wide range of business needs.

The City also offers a robust retail sector with over 5 million square feet of retail space, three-quarters of which is in shopping centers. Milpitas features more than 150 national and regional retailers, along with an ethnically diverse mix of restaurants and sp ecialty stores, many focused on Asian products. Major regional shopping destinations include the 1.4 million-square-foot Great Mall and the 415,000-square-foot McCarthy Ranch retail center.

3.5 Land Uses within Service Area
There are approximately 14 square miles of land within the City boundaries. The primary land uses in the developed portions of the City are residential, commercial, and industrial. The distribution of land uses provided by the City of Milpitas Planning Department are consistent with the City of Milpitas 2040 General Plan adopted March 9, 2021.

City of Milpitas 2025 Urban Water Management Plan DRAFT 29 4 CUSTOMER WATER USE
Lay Description
The Water Code requires a description and quantification of water uses in the service area , including recycled water if used or may be used in the future . This chapter describes and quantifies the City ’s historical, current (2025), and future water use projections through 205 0, based on available r ecords. Also presented in this chapter is a summary of distribution system water losses (i.e., leakage from pipes, under- registering meters, etc.). Future water use is based upon the City’s past and existing water use (as of 2025), along with anticipated growth, new regulations, changing climate conditions, and trends in customer water use behavior. A thorough analysis examined each water use sector and aggregated the results into a comprehensive projection of customer water use.

Table 4-1 and Table 4-2 present the City’s actual total 2025 water consumption and projected water demands through 2050, respectively by water use sector.

4.1 Non-Potable Versus Potable Water Use
The City purchases recycled water from SBWR and operates and maintains the recycled water distribution facilities within City boundaries, which is discussed in greater detail in Chapter 6 of this UWMP. The tables in this chapter summarize total current water use and projected water use, including recycled water.

4.2 Past, Current, and Projected Water Use by Sector
This section will identify water use, based on available records, for the 10 water use sectors identified in Water Code Section 10631(d).16 Also included is a description of how sector water use is calculated and projections are estimated.

The BAWSCA 2025 Regional Water Demand and Conservation Projections Study model was used to project long- term demand, through 2050, based on expected service area growth for population and employment. Demand forecasts were developed for each agency , considering conservation from passive (i.e., from codes/standards) and active conservation programs. Based on this analysis, water demands were projected after accounting for the effects of the existing plumbing code and future active conservation savings. BAWSCA also evaluated conservation measures for potential future regional implementation . The City’s conservation measures are discussed in Chapter 9 – Demand Management Measures.

4.2.1 Water Use Sectors Listed in Water Code
For the demand analysis, the City provided 2020 -2023 water use sectors, water rates, monthly water consumption and water conservation data, production data, and additional information for historical and projected use analyses. Based on the City’s water demand projection analysis that was conducted , the City describes its past, current, and projected water use for its water use sectors, in five -year increments through 2050.

The following water sectors are listed in the Water Code , with additional sectors or subdivisions included as needed to reflect unique conditions for sectors or subsectors not listed in the Water Code.

Single Family Residential
This is defined as a single family dwelling unit or a lot with a free-standing building containing one dwelling unit that may include a detached secondary dwelling. The City has approximately 12,500 single family accounts.

16 Water Code Section 10631.
http://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=WAT&sectionNum=10631 (leginfo.legislature.ca.gov

City of Milpitas 2025 Urban Water Management Plan DRAFT 30 Among the City’s new residential development are some single family units. However, overall, the City’s newer housing is shifting from the traditional suburban single family home with individual yards to urban high-density housing units.

Multifamily Residential
This is defined as multiple dwelling units contained within one building or several buildings within one complex.

The City has approximately 2,000 multifamily accounts serving approximately 15,500 dwelling units. These share outdoor space, and some are combined with retail and office space as described in the Specific Plans for future development around the BART station. This demand sector is projected to have significant growth as a result of numerous residential and mixed -use developments under constructi on, approved, pending entitlement , or in plan review. The City includes mobile homes in the multifamily classification.

Commercial
This is defined as a water user that provides or distributes a product or service. The City has a complex mix of commercial customers, ranging from beauty shops, supermarkets, and gas stations to multi- story office buildings, outlet and regional shopping centers, high-volume restaurants, and other facilities serving the visitor population.

Industrial
This is defined as a water user that is primarily a manufacturer or processor of materials as defined by the North American Industry Classification System (NAICS)
17 code sectors 31-33 or an entity that is a water user primarily engaged in research and development , per Water Code Section 10608.12(h). 18 The City retains research and development facilities, along with some food preparatory facilities.

Institutional/Governmental
This is defined as a water user dedicated to public service. This type of user includes, among other users, higher- education institutions, schools, courts, churches, hospitals, government facilities, and nonprofit research institutions per Water Code Section 10608.12(i). 19 The City has a stable institutional/governmental sector, including local government, schools, a county correctional facility, and outpatient medical facilities.

Landscape
This is defined as w ater connections supplying water solely for landscape irrigation. Such landscapes may be associated with multifamily or CII/governmental sites but are considered a separate water use sector if the connection is solely for landscape irrigation. Irrigation demand is anticipated to increase slightly due to continued development and redevelopment. However, requirements for newly developed and reconstructed landscapes to be more water efficient, ongoing outdoor water conservation programs , nonfunctional turf watering prohibitions for CII properties , landscape conversions to recycled water , and increased efficiency in irrigation systems are expected to offset future increases in potable water demand for landscaping.

17 North American Industry Classification System website, accessed April 2026: https://www.census.gov/naics/ 18 Water Code Section 10608.12(h).
http://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=WAT&sectionNum=10608.12 19 Water Code Section 10608.12(i).
http://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=WAT&sectionNum=10608.12

City of Milpitas 2025 Urban Water Management Plan DRAFT 31 Sales to Other Agencies
As a retailer, the City purchases water for its own use and does not sell water to other agencies; therefore, this section is not applicable.

Groundwater Recharge
This is defined as the managed and intentional replenishment of natural groundwater supplies using man-made conveyances such as infiltration basins or injection wells. Water used for groundwater banking or storage may also be reported using this sector. If all, or a portion of, the groundwater recharge water is subsequently pumped out of the basin in the same year, that water will be reported as groundwater. The City does not have groundwater recharge; therefore, this section is not applicable.

Saline Water Intrusion Barrier
This is defined as the injection of water into a freshwater aquifer to prevent the intrusion of saltwater. The City does not have a saline water intrusion barrier; therefore, this section is not applicable.

Agricultural
This is defined as water used for commercial agricultural irrigation. The City does not have agricultural irrigation; therefore, this section is not applicable.

Distribution System Water Loss
Distribution system water losses (also known as “real losses”) are the physical water losses from the water distribution system and storage facilities, up to the point of customer consumption. The water loss projections were developed, assuming the ratio of water loss to other categories of demand remains constant over the planning horizon. See Section 4.3 for further details.

4.2.2 Water Use Sectors in Addition to Those Listed in Water Code The water use sectors described below are not specifically listed in, nor required by, the Water Code.

Exchanges
Water exchanges are typically water delivered by one water user to another, with the rec ipient returning the water at a specified time or when the conditions of the parties’ agreement are met. Water exchanges can be strictly a return of water on a basis agreed upon by the participants or can include payment along with the return of water. Water can be returned on a one -for-one basis or by another arrangement (e.g., for each acre -foot of water received, two are returned). For more information on this water use sector, refer to Section 6.2.7.

Surface Water Augmentation
This is defined as t he planned placement of recycled water into a surface water reservoir used as a source of domestic drinking water. The City does not participate in surface water augmentation; therefore, this section is not applicable.

Transfers
The Water Code defines a water transfer as a temporary or long-term change in the point of diversion, place of use, or purpose of use due to a transfer, sale, lease, or exchange of water or water rights. Transfers can be between neighboring Suppliers or ac ross the state, provided there is a means to convey or store the water. A water transfer can be a temporary or permanent sale of water or a water right by the water right holder, a lease of the right to use water from the water right holder, or a sale or lease of a contractual right to water supply.

Water transfers can also take the form of long -term contracts to improve long-term supply reliability. Some

City of Milpitas 2025 Urban Water Management Plan DRAFT 32 Retail Suppliers transfer water to other suppliers. The City does not participate in water transfers; therefore, this section is not applicable.

Wetlands or Wildlife Habitat
This is defined as water used for a managed environmental use to improve environmental conditions. The City does not manage a wetlands or wildlife habit program; therefore, this section is not applicable.

Other
The City has approximately 6 00 fire service accounts. The Other usage shown in this chapter is water use associated with fire service accounts.

4.2.3 Past Water Use
While not part of the DWR UWMP Reporting Tables, the Water Code requires Retail Suppliers to quantify past water use. Past water use is valuable during development of projected uses as it helps create an understanding of water use trends, the effects of temporary use restrictions imposed during the most recent prolonged drought and recovery from such temporary restrictions , the effects of long-term demand management measures, and other pertinent water use factors. The City’s historical water use is part of the data that was used for the City’s collaboration in the BAWSCA Regional Water Demand and Conservation Projections Study; the BAWSCA Demand Study identified demand and conservation projections through 20 50. The BAWSCA Demand Study analyzed the City’s historical data from 2000 –2023 to assess the impacts of certain factors (e.g., water rates, economic conditions, and weather) on water demands.

4.2.4 Current Water Use
This section presents current water use as ascertained by analyzing information such as meter data, billing records, and others as well as recently submitted Electronic Annual Reports (eAR) and monthly reports. Current water use is reflected in Table 4-1 which includes current gross and recycled water use. As shown in Table 4-1, for 2025, the City’s service area used a total of 3,238 million gallons (MG) of potable water. In 2025, of the City’s total potable water use, approximately 27% was in the single -family residential sector, while 23% was in the multifamily sector. Of the Commercial, Institutional, and Industrial sector (CII), about 11% was Commercial, 11% Industrial, 4% Institutional, 8% Irrigation, and 0.05% Other.

City of Milpitas 2025 Urban Water Management Plan DRAFT 33 Table 4-1. Demands for Potable and Non-Potable Water – Actual Submittal Table 4-1 Retail: 2025 Actual Total Uses for Potable and Non-Potable Water - Water Code Section 10631(d)(1)
Use Type Additional Description 2025 Actual Water Use
Level of
Treatment
When Delivered
Volume
(MG)
Single Family Potable 812
Multifamily Duplex, Townhouse, Condo, Mobile Homes Potable 693 Commercial Potable 333
Industrial Potable 314
Institutional/Governmental Schools, Government or Church and City Domestic Accounts Potable 108
Landscape Potable 231
Other (optional) Fire Potable 2
Distribution System Water Loss Potable water loss Potable 472 Other (optional)
Recycled water for industrial reuse and
commercial, industrial, institutional
landscapes
Non-Potable 273
Subtotal Potable 2,965
Subtotal Non-Potable 273
Total 3,238
NOTES:

1. The City tracks CII uniquely in its billing and consumption recording, but in its projections has combined these uses into one category.

2. Distribution System Water Loss is calculated as the difference between total customer category use and production.

4.2.5 Projected Water Use
This section presents projected water use for each sector, in five-year increments through 2050. Projected water use is reported in Table 4-2. Water use projections were developed using long-term population and employment growth projections, 2022-2023 base water use for residential sectors and 2021 -2022 for the CII sector, which includes plumbing codes and standards. The demand projections were based on an econometric model, which included the City’s specific economic conditions, retail water rates, population, monthly production data from 1980-2023, and impact s of drought restrictions implemented during the 2021- 2023 period. The econometric model generated water demand forecast s to 2050 and was developed during the City’s participation in BAWSCA’s 2025 Regional Water Demand and Conservation Projections Study. 20 The Demand Study is described
further in the BAWSCA text that follows.

20 Demand Study:
https://bawsca.org/uploads/userfiles/files/2025%20BAWSCA%20Demand%20Study_Final%20Report%20%2B%20Appendi ces_submittal%281%29.pdf

City of Milpitas 2025 Urban Water Management Plan DRAFT 34 The demand model used to prepare the projections established a base-year water demand for each type of water use sector (e.g. single family, multifamily, CII , dedicated irrigation, recycled water accounts, etc. ).

Forecasting future demand involved determining the growth in the number of water service accounts. Once the rates of change were established, they were entered into the model and applied to those account types (BAWSCA, 2025).

The next step in developing future demand was to evaluate the cost effectiveness and water savings of a variety of potential water conservation measures to determine how much of the projected demand can be reasonably met through demand management. The pote ntial water conservation savings were deducted from the total demand. The model also incorporated the effects of plumbing and appliance codes, or so-called passive savings, on existing and future accounts, as well as anticipated land use changes, densification , and industrial development anticipated in the City and supported by General Plan policies and strategies.

Development Factors Affecting Water Demand
The water demand projections summarized in this section incorporate anticipated development factors within the City, affecting both residential and non-residential sectors. The potable water demand projections are built off BAWSCA’s 2025 Demand Study demand model, which estimated total water demand at year 205 0 to be 3,611 million gallons (Table 4-2). Of the total 2050 demand, 3,331 million gallons are anticipated to be potable and 280 million gallons to be recycled water.

The Association of Bay Area Governments ( ABAG) identify RHNA numbers based on the California Department of Housing and Community Development ’s (HCD’s) determination of the total number of new homes the Bay Area needs to build to meet the housing needs of people at all income levels. In 2021, the ABAG Executive Board adopted final RHNAs for the 2023-2031 cycle. The BAWSCA study used growth rates from ABAG Plan Bay Area 2050 and applied these to recent and historical data to derive a projection. The service area’s RHNA target values were cross-checked against these to ensure compliance.

BAWSCA Standard Text
The goal of the Demand Study was to develop transparent, defensible, and uniform demand and conservation savings projections for each Wholesale Customer using a common methodology to support both regional and individual agency planning efforts and complian ce with the new statewide water efficiency targets required by Assembly Bill (AB) 1668 and Senate Bill (SB) 606.

Through the Demand Study process, BAWSCA and the Wholesale Customers (1) quantified the total average-year water demand for each Wholesale Customer through 2050, (2) quantified passive and active conservation water savings potential for each individual Who lesale Customer through 2050, and (3) identified conservation programs with high water savings potential and/or BAWSCA Member Agency interest. Implementation of these conservation measures, along with passive conservation, is anticipated to yield an additional 16.14 million gallons per day (MGD) of water savings by 2050. Based on the revised water demand projections, the identified water conservation savings, increased development and use of other local supplies by the Wholesale Customers, and other actions , the collective purchases of the BAWSCA Member Agencies from the SFPUC are projected to stay below 184 MGD through 2050.

As part of the Demand Study, each Wholesale Customer was provided with a demand model that can be used to support ongoing demand and conservation planning efforts, including UWMP preparation.

City of Milpitas 2025 Urban Water Management Plan DRAFT 35 Table 4-2. Demands for Potable and Non-Potable Water – Projected Submittal Table 4-2 Retail: Total Uses of Potable, and Non-Potable Water - Projected Water Code Section 10631(d)(1)
Use Type
Additional
Description
Projected Water Use

Level of
Treatment
When Delivered
2030 2035 2040 2045 2050 (opt)
(MG) (MG) (MG) (MG) (MG)
Single Family Potable 730 710 695 680 660
Multifamily
Duplex,
Townhouse,
Condo,
Mobile
Homes
Potable 690 760 820 860 890
Commercial
Commercial,
Industrial,
Institutional
(schools,
government,
church, City
domestic
accounts)
Potable 870 910 960 1,000 1,000
Landscape Potable 280 280 280 280 280
Distribution
System Water
Loss
Potable 430 450 470 490 500
Other
(optional) Fire Potable 1 1 1 1 1
Other
(optional)
Recycled
water for
irrigation &
industrial
reuse
Non-Potable 275 275 275 280 280
Subtotal Potable 3,001 3,111 3,226 3,311 3,331
Subtotal Non-Potable 275 275 275 280 280
Total 3,276 3,386 3,501 3,591 3,611
NOTES:

1. Projected demands were developed as part of the 2025 BAWSCA Regional Water Demand and Conservation Projections Study. Demand projections utilized climate change scenario Representative Concentration Pathway (RCP) 8.5 and include passive savings associated with plumbing codes and natural fixture replacement, and active conservation savings from ongoing water conservation programs.

2. Demands over 8 MG are rounded to the nearest 10 MG.

3. The BAWSCA Demand Study's baseline scenario (and therefore this UWMP's projection) holds system water loss at a constant share of total consumption in the future, consistent with Milpitas' 2023 AWWA water loss reporting. As total demand grows or declines, the volumetric system water loss moves proportionally, but the percentage remains constant.

City of Milpitas 2025 Urban Water Management Plan DRAFT 36 20-Year Planning Horizon
In accordance with Water Code Section 10635(a), all Suppliers will need to report their projected water use in five-year increments through 2045 and are encouraged to project through 2050.

In accordance with Water Code Section 10603(d)(2), the City project ed its water use through 2050 in five-year increments in Table 4-2 and provided these projected demands to Valley Water and SFPUC (through BAWSCA).

The BAWSCA Demand Study, that is available to SFPUC, incorporates projected water savings from the plumbing code, standards, ordinances, and projected demands due to growth in the City’s service area.

Codes and Other Considerations Used in Projections
Water savings from codes, standards, ordinances, and land use planning, also known as passive savings , generally decrease water use for new and future customers compared to existing customers. However, some ordinances and standards may also apply to existing customers, such as plumbing code changes resulting in fixture and appliance replacements. Suppliers are required to state the extent to which passive savings are considered in these water use projections. This is noted in Table 4-3 and quantified in Table 4-4.

The water demand projections in Table 4-2 are based on analysis of historic metering data and projected growth in population, jobs, and development presented in the 202 5 BAWSCA Demand Study. The projections in Table 4-2 include reductions due to “plumbing code” upgrades and reflect on-going change-outs of existing plumbing fixtures for more water efficient devices and the implementation of conservation measures selected by the City.

Retail Suppliers are required to include any estimated passive savings expected in their water -use projections pursuant to Water Code Section 10631(d)(4)(A) and future water projections needed for lower income residential water use pursuant to Water Code Section 10631.1.

The City include s in its 2025 UWMP the projected water use for lower income households (i.e., those with income below 80% of area median income, adjusted for family size) , using population numbers from the 2025 BAWSCA Demand Study. However, it should be noted that the City does not use this estimate for any planning purposes. Projected water use by lower income households is estimated by multiplying the projected housing need for the City by the average household size and assumed per capita water use. The most recent source of data for low-income housing units for the City is the 2023-2031 Housing Element, which was adopted on January 24, 2023.

Water usage for lower income housing units a nd passive water savings estimates are included in the overall water demand projections, as shown below in Table 4-3.Table 4-3. Inclusion in Water Use Projections Submittal Table 4-3 Retail: Inclusion in Water Use Projections Water Code Section 10631 (a), 10631 (d)(4)(A), and 10631 (d)(4)(B) Are Future Water Savings Included in Projections? Yes
If "Yes" to above: State the section or page number, in the cell to the right, where citations of the codes, ordinances, or otherwise are utilized in demand projections are found.

Section

4.2.5 Are Lower Income Residential Demands Included in Projections? Yes NOTES: All of the City of Milpitas' residential customers, regardless of income level, are metered. Thus, the demands of residential customers with lower incomes are part of the single-family and multifamily water uses as shown in Table 4-1 and Table 4-2.

The City is using optional Submittal Table 4-4 to report its projected passive water-use savings. The “Description” column presents the ordinance, plan, or other information that will bring about the expected passive savings.

Table 4-4. Passive Water Savings Projections
OPTIONAL Submittal Table 4-4 Retail: Passive Water Savings Projections - Water Code Section 10631(d)(4)(A)

City of Milpitas 2025 Urban Water Management Plan DRAFT 37 Description
(Codes, Standards, Ordinances, or Plans)
Passive Savings
2030 2035 2040 2045 2050
(MG) (MG) (MG) (MG) (MG)
Passive Conservation 56 100 133 157 178
Active Conservation 44 69 85 100 116
NOTES:

1. Projected demands were developed as part of the 2025 BAWSCA Regional Water Demand and Conservation Projections Study, utilizing climate change scenario Representative Concentration Pathway (RCP) 8.5.

2. Passive conservation includes savings associated with plumbing codes and natural fixture replacement, and active conservation includes savings from ongoing water conservation programs. The basis for passive and active savings volume can be found in Section 4 of the 2025 BAWSCA Regional Water Demand and Conservation Projections Study.

4.3 Distribution System Water Loss
Distribution system water losses ( also known as “real losses”) are the physical potable water losses from the pressurized water distribution system and the storage facilities up to the point of delivery to the customer’s system (e.g., up to the residential water meter) calculated using the American Water Works Association ’s (AWWA) Method (Title 23 California Code of Regulations [CCR] Section 638.1 et seq.). This is the sum of the AWWA Method real losses and apparent losses.

In the 2025 UWMP, distribution system water loss for each of the five years preceding the plan update must be reported (Water Code Section 10631(d)(3)) in accordance with the rules adopted pursuant to Water Code Section 10608.34 . Table 4 -1 and Table 4 -2 present current and projected distribution system water losses representing total non -revenue water volumes which include real losses, apparent losses , and unbilled authorized consumption.

To better understand the nature of non -revenue waters, the City completed its first detailed Water Audit and Component Analysis of Real and Apparent Losses in 2015, utilizing the AWWA Method. This method uses known factors, such as system input volume, authorized consumption, and revenue water to determine water losses.

These losses are further categorized into two types:
• Apparent losses – Due to meter inaccuracies, data errors and theft. The water is consumed but is not properly measured and accounted for.
• Real losses – Due to system leaks and breaks.

Through these efforts and other measures, real losses have been reduced significantly. Table 4-5 shows that the City has submitted Water Audits for Water Use Efficiency (WUE) for the last five years, including the most recent reporting period January 1, 2024, through December 31, 2024; links to each report are provided.

City of Milpitas 2025 Urban Water Management Plan DRAFT 38 Table 4-5. Water Loss Audit Reporting
Submittal Table 4-5 Retail: Water Loss Audit Reporting - Water Code Section 10631(d)(3)(A)
Public Water
System ID #
Reported in
Table 2-1 R
Reporting
Period
Submitted
to DWR
Water
Loss Audit
Program
(yes/no)
Link to the WUEdata submittals of
Water Loss Audit Reports
Report submittal status for all five years for each Public Water System as available. 4310005
2020 Yes WUEdata - 2020
2021 Yes WUEdata - 2021
2022 Yes WUEdata - 2022
2023 Yes WUEdata - 2023
2024 Yes WUEdata - 2024
In Table 4-6, the City’s defines its Water Loss Performance Standard. Each relevant Public Water System and its associated standard (s) are listed in the table, along with relevant information for converting between the performance standard and water loss volumes to determine progress toward meeting the water loss standard.

Submittal of this table and relevant data does not constitute compliance or non-compliance with the Water Loss Control Regulation which is governed by the State Water Board.

City of Milpitas 2025 Urban Water Management Plan DRAFT 39 Table 4-6. Progress Towards 2028 Water Loss Standard
Submittal Table 4-6 Retail: Progress Towards 2028 Water Loss Standard - Water Code Section 10631(d)(3)(C) Public
Water
System ID
#
Did the Water
Board Calculate
a Water Loss
Standard for this
Public Water
System?
Real Water Loss Apparent Water Loss
State Water Board
Standard
Most Recent AWWA
Water Loss Audit
Real Water
Loss Per
Unit per Day
State Water Board
Standard
Most Recent AWWA
Water Loss Audit
Apparent
Water Loss
Per Unit
per Day
2028 Real
Water
Loss
Standard
per Unit
per day
Units for
Real
Water
Loss
Number
of Units
(Connec
tions or
Miles)
Volume of
Total Real Loss
(MG)
2028
Apparent
Water Loss
Standard per
Unit per Day
Units for
Apparent
Water
Loss
Number of
Connections
Volume of
Total
Apparent
Loss
(MG)
4310005 Yes 34.9 GPSCD 16,750 404.4 66.1 12.9 GPSCD 16,750 62.6 10.2 NOTES: Connections include active and inactive accounts. GPSCD = gallons per service connection per day.

City of Milpitas 2025 Urban Water Management Plan DRAFT 40

4.4 Climate Change Considerations
The t ypes of climate change impacts considered in the water use projections include water demands , temperature, precipitation, and sea level rise. Following is the information upon which the projections are based.

The Public Policy Institute of California has predicted that five climate pressures will impact the future of California’s water management: warming temperatures, shrinking snowpack, shorter and more intense wet seasons, more variable precipitation, and rising seas.
21 As of 2019, some of these pressures are already apparent.

The climate impact on water supply is predicted to significantly exceed the impact on water demand.

Precipitation in the Bay Area will continue to have high variability . This will lead to cycles of wet years and dry years, with precipitation varying month by month within years as well. The largest winter storms in the Bay Area will likely become more powerful and potentially more damaging. The predicted increase in future temperature means California and the Bay Area could experience longer and deeper droughts, thereby impacting the water supply.

The Inter governmental Panel on Climate Change (IPCC) develop ed several future climate change scenarios referred to as Representative Concentration Pathways (RCPs).22 RCP 4.5 represents a mitigation scenario where global CO 2 emissions peak by the year 2040. RCP 8.5 represents the business -as-usual scenario where CO 2 emissions continue to rise throughout the 21st century. The following figure shows the spatial changes in annual mean maximum daily temperatures across the nine Bay Area counties under RCP 4.5 and RCP 8.5.

Figure 4-1. Bay Area Historical and Projected Mean Maximum Temperatures

Source: Ackerly et al. (University of California, Berkeley), 2018.

21 Public Policy Institute of California (PPIC). (2020). Priorities for California’s Water, accessed May 2025:
https://www.ppic.org/publication/priorities-for-californias-water/ 22 Intergovernmental Panel on Climate Change (IPCC). (2014). Climate Change 2014: Synthesis Report. Contribution of Working Groups I, II and III to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change . https://www.ipcc.ch/report/ar5/syr/

City of Milpitas 2025 Urban Water Management Plan DRAFT 41 According to California’s Fourth Climate Change Assessment San Francisco Bay Area Summary Report,23 the Bay Area’s historical temperature increased 1.7 degrees Fahrenheit from 1950 to 2005. It is predicted that annual mean maximum temperatures will increase by 1 to 2 degrees Fahrenheit in the early 21st century from the years 2006 to 2039, then will increase by an additional 3.3 degrees Fahrenheit in the mid -21st century from 2040 to 2069. This increment for the mid-21st century rises to 4.4 degrees Fahrenheit if the Bay Area remains under the high emissions scenario of “business-as-usual.”
The above IPCC report temperature change is broken into two time periods (early -21st century and mid -21st century).

Following are the considerations and methodology used to calculate the average annual temperature change for each of the IPCC report
24 time periods:
• Early 21st Century (2006-2039) had an estimated temperature increase of 1 to 2 degrees Fahrenheit that was averaged to 1.5 degrees Fahrenheit. For the 33-year time period, this equates to an average annual temperature increase of 0.045 degrees Fahrenheit.
• Mid-Century (2040-2069) was estimated to have a temperature increase of 3.3 degrees Fahrenheit. For the 29 -year time period, this equates to an average annual temperature increase of 0.114 degrees Fahrenheit.

Hotter and drier weather may lead to an increased demand in landscape irrigation. BAWSCA’s Demand Study model reflects the historical relationship of the City of Milpitas’ water demand with weather and then incorporates modeled weather under future climate change conditions into the Demand Study demand projections. Therefore, the demand projections presented in Section 4.2 include considerations of climate change. A description of the weather and climate change data incorporated into Milpitas’ demand model is provided in Section 5.4 of the BAWSCA Demand Study.

Downscaled CMIP5 data were obtained from CalAdapt’s Local Climate Change Snapshot tool. 25 Climate
projection data, including annual precipitation and maximum temperature, were collected for the three counties that overlay BAWSCA’s member agencies, including Alameda, San Mateo, and Santa Clara counties. Modeled temperatures from the CalAdapt CMIP5 RCP 4.5 and RCP 8.5 datasets were processed annually for 2025 through 2050 and included as potential inputs to the demand model. Table 4-7 summarizes the estimated increases in temperature between 2025 and 2050.

Table 4-7. Average Annual Maximum Temperature Increases in 2050 (Relative to 2025)* County RCP 4.5 RCP 8.5
Alameda 1.20 °F 2.03 °F
Santa Clara 1.25 °F 2.05 °F
San Mateo 1.06 °F 1.77 °F
*Information derived from CalAdapt CMIP5.

23 Ackerly, David, Andrew Jones, Mark Stacey, Bruce Riordan. (University of California, Berkeley). (2018.) San Francisco Bay Area Summary Report. California’s Fourth Climate Change Assessment. Publication number: CCCA4 -SUM-2018-005. https://www.energy.ca.gov/sites/default/files/2019-11/Reg_Report-SUM-CCCA4-2018- 005_SanFranciscoBayArea_ADA.pdf
24 Intergovernmental Panel on Climate Change (IPCC). (2014). Climate Change 2014: Synthesis Report. Contribution of Working Groups I, II and III to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change . https://www.ipcc.ch/report/ar5/syr/
25 CMIP5 Local Climate Change Snapshot Tool. https://cmip5.cal-adapt.org/tools/local-climate-change-snapshot

City of Milpitas 2025 Urban Water Management Plan DRAFT 42 According to the San Francisco Bay Conservation and Development Commission (BCDC) ,26 historical records show that sea level in San Francisco Bay has risen 18-20 cm (7 inches) over the past 150 years, as further detailed in the BAWSCA standard text that follows.

26 San Francisco Bay Conservation and Development Commission (BCDC): https://www.bcdc.ca.gov/wp - content/uploads/sites/354/2025/07/2025-06-25-introducing-the-regional-shoreline-adaptation-plan.pdf BAWSCA Standard Text
The updated 2018 State of California Sea -Level Rise Guidance recommends that projects in the San Francisco area with a lifespan to 2050 and under a high -emissions scenario (RCP 8.5), use three risk projections until 2050:
• Low risk aversion projection: 1.1 feet
• Medium-high risk aversion projection: 1.9 feet
• Extreme risk aversion projection: 2.7 feet
For highly vulnerable or critical assets that have a lifespan beyond 2050 and would result in significant consequences if damaged, the extreme risk aversion projection is recommended to be included in planning analyses. The range of low, medium-high, and extreme risk aversion projections should be evaluated across the range of high and low emissions scenarios (RCP 8.5 and RCP 2.6, respectively). For example, for a project with a lifespan to 2100, the recommended range of projections is as follows:
• Low risk aversion projection: 2.4 - 3.4 feet
• Medium-high risk aversion projection: 5.7- 6.9 feet
• Extreme risk aversion projection: 10.2 feet
The SFPUC assessment of the effects of climate change requires regular updating to reflect improvements in climate science, atmospheric/ocean modeling, observations, and human response to the threat of greenhouse gas emissions. Climate change research by SFPUC began in 2009 and continues to be refined.

SFPUC completed a Long Term Vulnerability Assessment in 2021, which assessed the impacts of climate change on the RWS, and amended it in 2024. Findings from the assessment are summarized in the following inset text boxes, and full details are available in SFPUC’s LVTA report.

SFPUC partnered with The Water Research Foundation to develop the Long Term Vulnerability Assessment (LTVA) of the RWS, to help quantitatively and qualitatively assess to what extent climate change will be a threat to the RWS in comparison to, or in combination with, other external drivers of change over the next 50 years (2020-2070). The LTVA assessed the potential effects of climate change on RWS water supply using a wide range of plausible increases in temperature and changes in precipitation to address the wide uncertainty in climate projections over the planning horizon. There are many uncertain factors, such as climate change, changing regulations, water quality, growth and economic cycles, that may create vulnerabilities for the RWS’s ability to meet Levels of Service. The uncertainties associated with the degree to which these factors will occur and how much risk they present to the water system are difficult to predict but were considered in this study. To address this planning challenge, the LTVA used a vulnerability-based planning approach to explore a range of future conditions to identify vulnerabilities, and to assess the risks associated with these vulnerabilities, that could lead to developing an adaptation plan that is flexible and robust to a wide range of future outcomes. The LTVA was completed in 2021, and the University of Massachusetts Amherst and The Water Research Foundation amended it in 2024.

City of Milpitas 2025 Urban Water Management Plan DRAFT 43

BAWSCA Standard Text
Key findings of the LTVA:
• Climate change exacerbates impacts from other external drivers of change and is not the single most important driver of vulnerability for the RWS.
• The RWS at a baseline demand of 227 MGD is resilient to changes in climate and other external drivers.
• The RWS water supply performance declines with reductions in mean precipitation but is mostly insensitive to increases in temperature.
• The RWS is more vulnerable to changes in demand and instream flow requirements than changes in mean annual temperature and precipitation.
• The RWS is vulnerable to changes to mean climate when demand or regulatory instream flow requirements increase.

Further results and conclusions from the LTVA and its amendment:
• According to climate projections and expert elicitations, there is a central tendency of warming of +2°C and +4°C by 2040 and 2070 (RCP 8.5), respectively, with no clear direction of change in mean annual precipitation over the planning horizon.
• In the upcountry region, by 2040, most projections and elicitations of warming estimate between +1°C and +4°C, and precipitation changes range between - 5% and +5%, compared to historical baseline; and by 2070, estimates of warming range between +3°C and +6 °C, and precipitation changes range between -15% and +15% (RCP8.5).
• Changes in hydrology due to climate change affect the RWS’s ability to meet water supply targets.

At 227 MGD baseline demand, the RWS can sustain up to +4°C and -5% precipitation change before failing to meet targets for delivery reliability, frequency of 20% rationing, storage reliability, and duration of rationing.
• Precipitation change is an important driver for RWS performance. A decrease by 10% or more will cause RWS water supply targets to be missed. The climate projections and expert elicitations show that such a change in precipitation is possible by 2040, altho ugh unlikely. The likelihood of this change increases toward 2070.
• The RWS shows minor sensitivity to temperature change for the metrics evaluated in this study.

Most metrics stay above target under warming conditions. However, warming conditions often magnify the loss in system performance if precipitation or demand change. • Demand change appears to be a major driver of future RWS performance. An increase in demand by 15% (265 MGD) will lead to failure to meet rationing frequency targets under current climate conditions. At 265 MGD demand, the rationing frequency targets would be met if there is an increase in precipitation of 10%. If demand increases by 30%, the rationing target cannot be met even when precipitation increases by 40%, which is believed plausible but unlikely over the planning horizon.
• The RWS is particularly vulnerable to state -amended new instream flow requirements below Don Pedro Dam, which represents a huge reduction in water available. Under all demand and climate scenarios the system reliability, defined as frequency of years without rationing, remains below 5%. • The RWS is also vulnerable to the draft Tuolumne voluntary agreement new instream flow requirements below Don Pedro Dam, which represents a large reduction in water available, although significantly less than for the state -amended new instream flow release s. The implementation of the draft Tuolumne voluntary agreement under current climate and demand conditions would reduce system reliability to 75%, which corresponds to the effects of a reduction in average rainfall by 20% under the current Federal Energy Regulatory Commission agreement.

City of Milpitas 2025 Urban Water Management Plan DRAFT 44 5 SB X7 - 7 BASELINES, 2020 TARGETS, AND 2025 REPORTING Lay Description
The Water Conservation Act of 2009, also known as Senate Bill (SB) X7- 7, mandated a 20% reduction in urban per capita water use across California by 2020. To achieve this goal, the Act required each Supplier to establish an urban water-use target, contributing to the State’s collective efforts. The Legislature stated that the combined reductions from all Suppliers would fulfill the statewide legislative mandate.

The goal of this chapter is to allow the Supplier to report on its progress toward meeting its urban water-use targets in its UWMP, pursuant to Water Code Section 10608.40. Suppliers that did not meet their 2020 target in 2020 are required to compare their 2025 water use to the 2020 target.

To be eligible for water related state grants and loans, Suppliers are required to comply with SB X7-7 individually or as a region in collaboration with other Suppliers or demonstrate they have a plan or have secured funding for compliance.

When determining water use in a UWMP, two terms are often used interchangeably:
• Daily Per Capita Water Use – The amount of water used per person per day. In the UWMP calculations, this is total water use within a service area divided by population and measured in gallons. • Gallons Per Capita Per Day (GPCD) – T his is the “daily per capita water use” as measured in gallons.

Therefore, the term commonly used when referring to “daily per capita water use” is “gallons per capita per day” or GPCD.

It is important to distinguish GPCD (as used in UWMPs) from the Residential GPCD (R-GPCD) that is used in some reporting to the State Water Board. GPCD is the total water use from all sectors within a service area (residential, commercial, institutional, and any others) minus allowable exclusions (as defined in SB X7- 7), then divided by the population. R-GPCD is only a part of the GPCD, the estimated residential water use in a service area divided by population.

5.1 Reporting Requirements
Chapter 9 contains a discussion of programs implemented to support the achievement of the City ’s per capita water reduction goals. The City met its 2020 Target in a timely manner as verified in the following Table 5-1 with information taken from the 2020 UWMP.

Table 5-1. SB X7-7 2020 Target Progress
Submittal Table 5-1 Retail: SB X7-7 2020 Target Progress - Water Code Section 10608.40 Was Supplier
part of a
merger or
consolidation
since 2020?
Regional
Alliance Target
or Individual
Target?
2020
Target
Actual
2020
GPCD
Did Supplier
Achieve
Targeted
Reduction for
2020?
Only For suppliers that did
not meet the Target in
2020
Actual 2025
GPCD
2020
Target met
in 2025?
No Individual
Target 146 108 Yes N/A N/A

5.2 Nexus to State Water Board Urban Water-Use Objectives The State Water Board’s “Making Water Conservation A California Way of Life” Regulation on Urban Water-Use Efficiency Standards, Objectives, and Performance Measures ( Title 23 C alifornia Code of Regulations [CCR] Section 965 et seq.) uses the 2020 Target as a backstop for the Urban Water Use Objective (UWUO) calculations.

City of Milpitas 2025 Urban Water Management Plan DRAFT 45 The City is currently meeting its UWUO as reported in its current annual UWUO report. The following table presents the City’s current actual use compared to its current UWUO as presented in the UWUO report.

Information about the City’s actions towards achieving its urban water use goals can be found in Chapter 9.

Table 5-2. FY ‘24/’25 Actual Use Compared to Urban Water Use Objective Water Use Component

Actual Water Use
(Gallons)
Urban Water Use
Objective (Gallons)
Total Residential Water Use, Indoor + Outdoor 1,523,301,674.62 1,975,095,584.93 Outdoor Irrigation of CII landscapes associated with
DIMs 242,001,554.47 242,001,554.47
System Water Loss 404,415,000.00 404,415,000.00
Variances, Provisions, and 20% INI buffer, if applicable N/A 0.00 Bonus Incentive N/A 0.00
Sum of Water Use Components (Specific to Objective) 2,169,718,229.08 2,621,512,139.40 Excluded Demands 1,053,876,603.06 1,053,876,603.06
Sum of Water Use Components (Objective + Excluded) 3,223,594,832.14 3,675,388,742.45 SB X7-7 Target Volume Plus Previously Excluded
Process and Recycled Water N/A 4,357,683,170.00
"Capped" Objective N/A 2,621,512,139.40
Regional Alliance Met Regional Target? (If Applicable) N/A N/A Final Comparison of Actual Water Use to Objective 2,169,718,229.08 2,621,512,139.40

City of Milpitas 2025 Urban Water Management Plan DRAFT 46 6 SYSTEM SUPPL IES
Lay Description
This section characterizes the City of Milpitas system supplies, including purchased or imported water, groundwater, surface water, stormwater, wastewater, recycled water , desalinated water, exchanges or transfers, future water projects, and any climate change impacts.

The water supply analysis focuses on characterizing each water asset in order to provide the information needed for reliability and risk assessments. The more accurately and detailed this characterization is, the better prepared the City will be for managing its water assets, assessing supply reliability, performing its DRA, and preparing and implementing its WSCP.

The source of the City’s water supply comes from two suppliers. Water from SFPUC is primarily from the Hetch Hetchy watershed located in the Sierra Nevada mountains. Water from Valley Water is primarily from the Sacramento-San Joaquin Delta watershed via t he South Bay Aqueduct, Dyer Reservoir, Lake Del Valle and San Luis Reservoir.

6.1 Water Supply Analysis Overview
This section will identify and quantify, to the extent practicable, the existing and planned sources of water available to the City in five-year increments to 20 years.

6.1.1 Specific Analysis Applicable to All Water Supply Sources The City currently has two sources of water (SFPUC and Valley Water) which are both wholesale water agencies.

Each system will be described separately below.

San Francisco Public Utilities Commission (SFPUC)
The City purchases potable water from SFPUC ’s Regional Water System (RWS) whose supply is predominantly snowmelt from the Sierra Nevada, delivered through the Hetch Hetchy aqueducts (see Figure 6 -1), but also includes treated water produced by SFPUC from its local watersheds and facilities in Alameda and San Mateo Counties. Water from the RWS is treated before delivery and supplied to the City from Bay Division Pipelines 3 and 4.

Detailed in Milpitas’ Water Master Plan, the City entered into a 25 -year Water Supply Agreement (WSA) with SFPUC on June 2, 2009. This agreement affirms the City’s perpetual right to purchase up to 9.232 MGD of treated potable water unless SFPUC has a water shortage. The WSA was amended and restated in 2025.

The amount of imported water available to SFPUC’s customers is constrained by climate, hydrology, physical facilities, and the institutional parameters that allocate the water supply of the Tuolumne River, the key source for SFPUC. Due to these constraints, SFPUC is very dependent on reservoir and snow-pack storage to manage its water supplies.

City of Milpitas 2025 Urban Water Management Plan DRAFT 47 Figure 6-1. City of Milpitas Water Sources – SFPUC Regional Water System Map

Source: SFPUC 2025 UWMP

City of Milpitas 2025 Urban Water Management Plan DRAFT 48 Valley Water (Formerly Santa Clara Valley Water District) The City began receiving treated surface water from Valley Water in August 1993 under a September 1984 contract between the City and Valley Water (previously known as Santa Clara Valley Water District). The supply delivery is adjusted annually based on a binding 3 -year annual delivery schedule. The City’s annual purchase must be at least 90% of the delivery schedule and the City’s monthly “supply guarantee” is at least 15% of the annual delivery schedule. Valley Water provides treated water from its Peniten cia and Santa Teresa treatment plants via its Milpitas Pipeline which terminates in the City.

Although the City purchases are currently limited to surface water largely purchased by Valley Water from the State Water Project and Central Valley Project, Valley Water’s overall water supply comes from a variety of sources. Nearly half is from local groundwater aquifers, and more than half is imported from the Sierra Nevada through pumping stations in the Sacramento -San Joaquin River Delta. Both groundwater and imported water are sold to retailers. Valley Water also manages the groundwater basin to the b enefit of agricultural users and other independent users who pump groundwater. Local runoff is captured in Valley Water reservoirs for recharge into the groundwater basin or treatment at one of Valley Water’s water treatment plants. The total storage capacity of these reservoirs is about 170,000 acre-feet (AF).

City of Milpitas 2025 Urban Water Management Plan DRAFT 49 Figure 6-2. City of Milpitas Water Sources – Valley Water Supply System Map

Source: Valley Water UWMP, 2025.

City of Milpitas 2025 Urban Water Management Plan DRAFT 50

6.1.2 Special Considerations
Numerous special conditions may affect water supplies. Each individual water supply may have specific conditions that may affect current or future supply characterization. The City considered climatological, regulatory, projected development, and other lo cal conditions that may affect water supply availability, especially when considering the supply’s availability for the service reliability and DRAs during single dry years and drought periods lasting five consecutive years. There are no additional charact erization considerations; all have been mentioned in Chapters 4, 6 and 7.

6.1.3 Climate Change Effects
The issue of climate change has become an important factor in water resources planning in the s tate and is frequently considered for urban water management planning purposes, though the extent and precise effects of climate change remain uncertain. The climate change impacts were discussed in Section 4.4.

Regulatory Conditions and Project Development
Emerging regulatory conditions and planned future projects may also affect characterization of future water supply availability and analysis. This does not apply to the City.

Other Locally Applicable Criteria
Other locally applicable criteria may also affect characterization and availability of an identified water supply.

This does not apply to the City.

6.2 Water Supply Characterization
The City’s water supply portfolio is described and quantified in the following subsections, including imported supplies and recycled water.

6.2.1 Purchased or Imported Water
The City purchases treated potable water from two wholesalers: SFPUC and Valley Water. These two sources are not blended under normal operating conditions. However, the distribution systems are physically interconnected with isolation valves to provide eme rgency water supply if needed. The 202 5 breakdown of actual water supplies is in Table 6-8. Projected (future) water supplies include the aforementioned sources and are provided in Table 6-9.

Following its incorporation year of 1954, the City began distributing SFPUC water to all residents and businesses, expanding to the hillside area in 1982. In August 1993, the City began serving water from Valley Water, primarily to the commercial and industrial areas of the City (west of Highway 880, and also south of Calaveras Blvd. and west of Highway 680). Figure 3-1, in Chapter 3, shows the SFPUC and Valley Water service areas.

Most of the City’s growth is occurring within areas served by Valley Water and as these areas grow so does the percentage of the City’s potable supply that comes from Valley Water. In 2025, approximately 35% of the City’s potable water came from Valley Water, which is a decrease from 40% in 2020.

City of Milpitas 2025 Urban Water Management Plan DRAFT 51

6.2.2 Groundwater
Agencies that pump, or expect to pump, groundwater are required to include in their UWMPs an overview of the groundwater resources and groundwater management strategies. Currently, the City does not use groundwater to meet customer demands under normal con ditions. The City has one existing fully developed well, Pinewood Well and two planned or in development : Curtis Well and McCandless Well. These wells are located in the southwestern part of the City (See Figure 6 -3). The Curtis Well was drilled in 2003, b ut the well was not equipped with above-grade infrastructure required for a functioning well, and the facility was never completed. As a result, bringing the Curtis Well online requires installing a submersible pump, piping and treatment components, as well as conducting testing and permitting. Design for the Curtis Well improvements began in 2020. Construction of the McCandless Well is scheduled to be completed in 2026.

The use of Pinewood Well, Curtis Well and McCandless Well as emergency wells or fully functioning wells is yet to be studied, however the significance of these wells cannot be understated. In 2015, the State Water Resources Control Board Division of Drinking Water (DDW) requested a formal evaluation of the City’s Water Source Capacity, under Section 64558, Title 22,
27 of the California Code of Regulations. The use of well(s) for storage credits is one strategy the City may use to supplement above grade storage requirements to satisfy Section

27 Title 22 California Code of Regulations § 64558: Source Capacity Planning Study . https://www.law.cornell.edu/regulations/california/22-CCR-64558 Valley Water Standard Text
Major sources of supply for Valley Water include natural groundwater recharge, local surface water, imported water from the SWP and CVP, and recycled and purified water.

Imported
Much of Valley Water’s current water supply comes from hundreds of miles away from natural runoff and releases from statewide reservoirs. This imported water is pumped out of the Delta and brought into the county through the complex infrastructure of the S WP and CVP. Valley Water holds contracts for 100,000 acre-feet per year (AFY) from the SWP and for 152,500 AFY from the CVP. The actual amount of water delivered is typically less than these contractual amounts and depends on hydrology, conveyance limitations, and environmental regulations.

Constraints on imported water:

Imported water supplies are subject to hydrologic variability. Local and out-of-county storage can help mitigate the impacts of hydrologic variability.

Valley Water’s SWP and CVP water supplies are also subject to a number of additional constraints including regulatory requirements to protect fisheries and water quality in the Delta, and conveyance limitations. Delta-conveyed supplies are also at risk fro m Delta levee failures due to seismic threats and flooding, sea level rise and climate change, declining populations of protected fish species, and water quality variations (including algal blooms). Many water quality variations are addressed, by blending sources and/or switching sources to the drinking water treatment plants. Algae and disinfection byproduct precursors have been especially challenging during recent drought conditions.

To address at least some of these constraints, Valley Water continues to evaluate the costs and benefits of participating in the Delta Conveyance Project relative to other water supply options such as developing additional local supplies, securing and optimizing Valley Water’s existing water system, and expanding water conservation.

City of Milpitas 2025 Urban Water Management Plan DRAFT 52 64558, Title 22. A Source Capacity Analysis, as part of a separate study independent of the UWMP, was performed by the City. On August 9, 2022, the City adopted a Water Master Plan which identified the City’s current and future water demands and the infrastructure required to address source capacity. The Master Plan Study informed the City’s Source Capacity Analysis. However, preliminary evaluations indicate a combination of groundwater supply in conjunction with above grade storage (tanks) may be the appropriate balance to ensure compliance with Sect ion 64558 of Title 22. Additionally, expanding the City’s water portfolio to include groundwater wells will supplement loss of supply as a result of wholesale cutbacks in the event of prolonged droughts as discussed in Chapter 7. Pinewood Well is permitted for use as a standby emergency well. The City currently reserves groundwater supply for emergency use in the event that SFPUC and Valley Water cannot deliver contract treated water supplies.

Basin Description & Basin Management Information
The local groundwater basin is called the Santa Clara Valley Sub -basin. The basin is made up of unconsolidated alluvium. Within City boundaries, the eastern portion of the basin is unconfined and does not contain an aquitard to prevent contamination from spreading from surface to groundwater. The western portion of the City overlies a confined, aquitard-protected area with water of good quality.

Figure 6-3. City of Milpitas Groundwater Resources

Source: City of Milpitas Water Master Plan. West Yost. (2020)

City of Milpitas 2025 Urban Water Management Plan DRAFT 53 Other Considerations
The Santa Clara Valley Sub -basin is not adjudicated and has not been identified as in overdraft by DWR.

Neighboring utilities, including the City of Santa Clara and the City of San Jose, utilize the groundwater basin.

The basin has historically experienced periods of overdraft and land surface subsidence, particularly during the 1920s and 1960s when expanding development and agricultural production increased demand. The Santa Clara Valley Water Conservation District (today’s Valley Water) was originally formed in 1929 to alleviate subsidence through artificial recharge. Valley Water manages the groundwater basin, monitoring the basin for local subsidence, managing surface recharge, and working with local retailers to prevent subsidence. For more information on basin characteristics and management, please refer to Valley Water’s Groundwater Management Plan.
28 Additionally, the City may expand its managed groundwater well extraction program to supplement loss of supply as a result of wholesale cutbacks in the event of prolonged droughts as discussed in Chapter 7.

Table 9-2 of the Water Master Plan (as shown in Figure 6-4) summarizes the location and capacity for each of these wells.

Figure 6-4. Location and Capacity of Emergency Groundwater Wells at Buildout

Source: City of Milpitas Water Master Plan. West Yost. (2020) Past Five Years’ Groundwater Pumping
Table 6-1 shows the historical annual volume of groundwater pumped over the past five years. This groundwater was pumped only for the purpose of routine water quality testing. It was not added to the municipal water supply.

Table 6-1. Groundwater Volume Pumped
Submittal Table 6-1 Retail: Groundwater Volume Pumped - Water Code Section 10631(4) and 10631(4)(c) Groundwater Type Location or Basin Name 2021 2022 2023 2024 2025 (MG) (MG) (MG) (MG) (MG)
Alluvial Basin Santa Clara Valley, Santa Clara Sub-basin 0.06 0.03 0 0 0 Total 0 0 0 0 0
NOTES: Groundwater pumped during reporting period was for testing purposes only. No groundwater was pumped into the distribution system.

28 2021 Groundwater Management Plan for the Santa Clara and Llagas Subbasins . https://s3.us-west-

2.amazonaws.com/assets.valleywater.org/2021_GWMP_web_version.pdf

City of Milpitas 2025 Urban Water Management Plan DRAFT 54 Table 6-1 shows the projected annual volume of groundwater pumped, in five-year intervals. The projection is based on well capacity values reported in the Water Master Plan and reflects a tiered introduction of groundwater into the municipal supply. Capacity for McCandless Well (currently under construction) is based on discussions with the design team and production testing, which was performed at the end of 2020. It was conservatively assumed that Curtis Well would have the same capacity as McCandless Well (0.58 MGD).

However, the Curtis Well capacity is subject to change.

6.2.3 Surface Water
Water from streams, lakes, and reservoirs is considered a surface water supply for the purposes of the UWMP.

Surface water supplies for the City are reported in Tables 6-8, 6-9, and 7-1. Surface water that is not self-supplied will be reported as Purchased or Imported Water in Tables 6-8 and 6-9.

6.2.4 Stormwater
Communities are increasingly implementing opportunities to beneficially use stormwater to meet local water supply demands. These actions are motivated by constrained local water resources, new regulations, and relieving strain on overburdened stormwater in frastructure. Beneficial uses can include blending with other waters supplies for groundwater recharge, redirecting it into constructed wetlands or landscaping, and diverting it to a treatment facility for subsequent reuse.

The City is not currently using its stormwater but could consider this in the future.

6.2.5 Wastewater and Recycled Water
Per Water Code 10633, the UWMP shall provide to the extent available, information on recycled water and its potential for use as a water source in the service area of the urban water supplier. The preparation of the plan shall be coordinated with local water, wastewater, groundwater, and planning agencies that operate within the supplier’s service area, and shall include all of the following:
• A description of wastewater collection and treatment systems in the supplier’s service area. • A description of the quantity of treated wastewater that meets recycled water standards, is being discharged, and is otherwise available for use in a recycle water project. • A description of the recycled water currently being used in the supplier’s service area, including, but not limited to, the type, place, and quantity of use.
• A description and quantification of the potential uses of recycled water, including, but not limited to, agricultural irrigation, landscape irrigation, wildlife habitat enhancement, wetlands, industrial reuse, groundwater recharge, indirect potable reuse, and other appropriate uses, and a determination with regard to the technical and economic feasibility of serving those uses. • The projected use of recycled water within the supplier’s service area at the end of 5, 10, 15, and 20 years, and a description of the actual use of recycled water in comparison to uses previously projected pursuant to this subdivision.
• A description of actions, including financial incentives, that may be taken to encourage use of recycled water, and projected results of these actions in terms of acre-feet of recycled water used per year.

Municipal recycled water is municipal wastewater that has been treated to a specified quality to enable it to be used again for a beneficial purpose. The term “recycled water” is defined in the Water Code more broadly than “municipal recycled water.” For purposes of the UWMPs, “recycled water” means only municipal recycled water, that is, water that has been treated and discharged from a municipal wastewater facility.

City of Milpitas 2025 Urban Water Management Plan DRAFT 55 There are two requirements that treated municipal wastewater must meet to be classified as recycled water:

1. It must be reused beneficially, in a manner consistent with Title 22.

2. It must be reused in accordance with a Regional Water Quality Control Board permit such as National Pollutant Discharge Elimination System, waste discharge requirement, or water recycling requirement.

Recycled Water Coordination
As a tributary agency to the San Jose/Santa Clara Regional Wastewater Facility (RWF), the City has rights to the recycled water purveyed by SBWR. The City purchases recycled water from SBWR, as well as operates and maintains the recycled water distribution facilities within City boundaries. This is done through a contract with the City of San Jose, whereby Milpitas provides day -to-day operational services and helps to comply with recycled water permit requirements within the City. Design and construction cr iteria pertaining to recycled water are included in SBWR’s guidelines29 and Rules and Regulations.30 Wastewater Collection, Treatment, and Disposal
Per Water Code Section 10633(a), a supplier must provide a general description of wastewater collection, treatment, and disposal within the service area. This information is reported in Tables 6-2 and 6-3.

Wastewater Collected Within the Service Area
The City collects but does not treat wastewater within the service area. Rather, it pumps its wastewater, consisting primarily of industrial and sanitary discharge, through two force mains to the RWF. Table 6-2 includes the volume of wastewater collected in the service area.

Wastewater Treatment and Discharge Within the Service Area Wastewater treatment is provided by agreement with the cities of San Jose and Santa Clara (as joint owners of RWF). Under the terms of the agreement, the City pays a capital share (in proportion to the City’s 14.25 MGD capacity rights and the total p lant capacity) and pays an operating cost share based on discharge volumes to RWF, which is one of the largest advanced wastewater treatment facilities in California, treating an average of 110 million gallons of wastewater per day from 1.5 million residents and over 17,000 businesses, encompassing the cities of San Jose, Santa Clara, Milpitas, Campbell, Cupertino, Los Gatos, Saratoga, and Monte Sereno. Most of the final treated water is discharged into the South San Francisco Bay. Approximately 10% is supplied to SBWR for distribution to customers. Because the RWF is outside of the City’s service area, no volume numbers are included in Table 6-3, which is meant to identify the volume of treated wastewater recycled or disposed of within the service area.

Recycled Water System Description
Recycled water is predominantly used for landscape irrigation within the City but is also used for industrial use.

As indicated in Table 6 -4, landscape irrigation and industrial uses of recycled water are projected to continue growing within the City.

The City of San Jose in coordination with Valley Water is currently in the process of updating the SBWR Strategic and Master Plan from 2015, which describes and quantifies potential uses of recycled water throughout the

29 City of San Jose. Recycled Water web page: https://www.sanjoseca.gov/your-government/departments- offices/environmental-services/water-utilities/recycled-water 30 South Bay Water Recycling. Rules and Regulations For Design and Operation of On -Site Recycled Water Facilities . https://www.sanjoseca.gov/home/showpublisheddocument?id=526

City of Milpitas 2025 Urban Water Management Plan DRAFT 56 SBWR service area and addresses technical and economic feasibility of the potential uses, including non-potable and potable alternatives. Figure 6-5 depicts the City’s recycled water distribution system.

Figure 6-5. Recycled Water System

Source: City of San Jose Recycled Water web page. 31

31 City of San Jose. Recycled Water web page: https://www.sanjoseca.gov/your-government/departments- offices/environmental-services/water-utilities/recycled-water

City of Milpitas 2025 Urban Water Management Plan DRAFT 57 Table 6-2. Wastewater Collected Within Service Area in 2025 Submittal Table 6-2 Retail: Wastewater Collected Within Service Area in 2025 - Water Code Section 10633(a)

Check the box if there is no wastewater collection system. 99% Percentage of 2025 service area served by wastewater collection system 99% Percentage of 2025 service area population served by wastewater collection system Wastewater Collection Recipient of Collected Wastewater Name of
Wastewater
Collection Agency
Wastewater
Volume Metered
or Estimated?
Volume of
Wastewater
Collected from
UWMP Service
Area 2025
Name of Wastewater Treatment
Plant (WWTP) and Place ID
Number
Is WWTP
Located
Within UWMP
Area?
(MG)
City of Milpitas Metered 2,308 San Jose-Santa Clara Regional Wastewater Facility No
Total Wastewater Received from
UWMP Service Area in 2025: 2,308
NOTES: Approximately 99% of the service area and service area population served by the listed wastewater collection agency; does not include Spring Valley Heights Association (~25 units).

Table 6-3. Wastewater Treatment and Outcomes Within Service Area in 2025 Submittal Table 6-3 Retail: Wastewater Treatment and Outcomes Within UWMP Service Area in 2025 - Water Code Section 10633(a)

Check the box if no wastewater is treated or disposed of within the UWMP service area. Proceed to the next table.

Current, Potential and Projected Recycled Water Use
The recycled water projections in Table 6-4 include projects currently underway to convert potable users within the vicinity of the existing recycled water system, irrigation and indoor recycled water anticipated within Specific Plan areas, conversion of cooling towers as identified through a SBWR Cooling Tower Initiative and exten sion of the recycled water system to capture additional irrigation use. Every year, the City purchases approximately 275 million gallons of recycled water from the RWF, through the wholesale agency SBWR. The recycled water undergoes an extensive tertiary treatment process (including filtration and disinfection) and is delivered to approximately 250 recycled water customers in Milpitas, for landscape irrigation and industrial uses.

The recycled water system is part of the SBWR Strategic Master Planning Report completed in 2014. 32 The
Strategic Plan was divided into two phases , near term (2015-2020) and long term (2020-2035). Master Planning provides a basis for identifying alternative governance frameworks and associated funding strategies for non- potable water (i.e. recycled water). The SBWR system is currently developed to reflect near-term recycled water demands. The long-term plan is currently being studied, and future allocations have not been identified. Projected recycled water use is limited by the future supply allocations outlined by SBWR, and therefore not reflected in this UWMP.

32 South Bay Water Recycling Strategic and Master Plan (Final Report). https://www.valleywater.org/sites/default/files/335%20P3%20Related%20Reports%20SBWR%20Stratigic%20and%20Mast er%20Plan%20-%20Report%20%28Vol.1%29%20%281%29.pdf

City of Milpitas 2025 Urban Water Management Plan DRAFT 58 Table 6-4 contains information on the current, projected, and potential beneficial u se of recycled water in the City’s service area. The total projected recycled water use for each of the five-year planning increments is reported below in Table 6-4.

Table 6-4. Recycled Water Direct Beneficial Uses Within Service Area Submittal Table 6-4 Retail: Recycled Water Direct Beneficial Uses Within Service Area - Water Code Section 10633 (c)(e)

Check box if recycled water is not used and is not planned for use within the service area of the supplier. The supplier will only complete the column on "Potential Recycled Water Use" and submit an accompanying narrative on the feasibility of that potential recycled water use.

Name(s) of Facility/ies Producing
(Treating) the Recycled Water (OPTIONAL): City of San Jose Name of Supplier Operating the Recycled
Water Distribution System (OPTIONAL): South Bay Water Recycling Use Type
Water Type
(after treatment if
treated)
Additional Information
(as needed)
2025 2030 2035 2040 2045 2050
Potential Recycled
Water Use
(MG) (MG) (MG) (MG) (MG) (MG) Volume
Other (Description Required) Tertiary
Landscape irrigation for
commercial and
institutional sites, parks;
Industrial reuse
273 275 275 275 280 280 280
Total 273 275 275 275 280 280 0
NOTES: Projected recycled water demands were developed as part of the 2025 BAWSCA Regional Water Demand and Conservation Projections Study, which utilizes climate change scenario RCP 8.5. Recycled water projections reflect expected use of existing recycled water accounts. Potential Recycled water use based on 2050 projected use.

City of Milpitas 2025 Urban Water Management Plan DRAFT 59 Table 6-5. 2020 UWMP Recycled Water Use Projection Compared to 2025 Actual Submittal Table 6-5 Retail: 2020 UWMP Recycled Water Use Projection Compared to 2025 Actual - Water Code Section 10633 (e)

Check the box if recycled water was not used in 2025 nor previously projected for use in 2020.

Use Type 2020 Projection for 2025 2025 Actual Use
(MG) (MG)
Other (Description Required) 400 273
Total 400 273
NOTES:

1. The City's main uses for recycled water in 2025 were landscape irrigation at commercial, industrial, and institutional properties; and industrial reuse.

2. In the 2020 UWMP, projected recycled water use was based on the SBWR 2014 Strategic Master Plan Volume 1, and overestimated.

Actions to Encourage and Optimize Future Recycled Water Use Per Water Code Section 10633, the UWMP shall provide information on recycled water and its potential for use as a water source in the service area of the urban water supplier, and shall include a plan for optimizing the use of recycled water in the supplier service area, including actions to facilitate the installation of dual distribution systems, to promote recirculating uses, to facilitate the increased use of treated wastewater that meets recycled water standards, and to overcome any obstacles to achieving that increased use.

To encourage the use of recycled water, the City has an ordinance that prohibits the use of potable water for irrigation if recycled water is available and coordinates with SBWR and Valley Water on recycled water planning and implementation projects. The City has connected the recycled water infrastructure in its service area with that of neighboring San Jose Water (SJW), who is another SBWR retailer; this connection between the two retailer systems has improved overall reliability.

Table 6-6 details the methods planned to expand future recycled water use in the City’s service area.

Table 6-6. Methods to Encourage Future Recycled Water Use Check the box if the Supplier does not plan to expand recycled water use in the future. p. 59 Provide page location of narrative in the UWMP
Name of Action Description
Planned
Implementation
Year
Expected Increase in
Recycled Water Use
(MG)
Specific Plan
The City’s Transit Area Specific Plan policy
requires new development to include
recycled water lines for irrigation.

Existing Once SBWR allocation is
met
Ordinance
Ordinance 240.6, § 2 prohibits the use of
potable water for irrigation if recycled
water is available.
2017 Once SBWR allocation is
met
Total (MG) 0
Unit Conversion to AF 0

City of Milpitas 2025 Urban Water Management Plan DRAFT 60

6.2.6 Desalinated Water Opportunities
Desalination is the most cost -prohibitive of all treated waters available for the City, and as such the City does not plan to implement a desalination project at this time. However, desalination is still considered a viable option for a long -term augmentation method or back -up supply, especially with collaboration amongst neighboring agencies. The City’s Water Supply Augmentation Study recommended that the City consider a partnership with a regional water purveyor for a local desalination plant.

The City is aware of the Bay Area Regional Desalination Project, of which Valley Water is a partner. More information on the regional desalination project is available at http://www.regionaldesal.org/. Currently, Valley Water does not include desalination in its projected water supplies.

6.2.7 Water Exchanges and Transfers
Per Water Code section 10631(c), this section describes the opportunities for exchanges or transfers of water on a short-term or long-term basis. The information contained in this section will inform the quantification of water supplies incorporated into Tables 6-8 and 6-9.

Exchanges
Water exchanges are typically water delivered by one water user to another water user, with the receiving water user providing water in return at a specified time or when the conditions of the parties’ agreement are met.

Water exchanges can be strictly a r eturn of water on a basis agreed upon by the participants or it can include payment and the return of water.

Since the early 1990s, the water exchange market (including water rights trading) has expanded to account for approximately 5% of all water used annually by California businesses and residents. However, the approval process for water exchanges has become more complex and difficult as water contracts have shifted from short- term to several -year durations and as new pumping legislation has been introduced to address controversies arising from water banking, unprecedented droughts, and other issues. It is a result of these complications that the City does not have, or plan to have, any exchange opportunities for the purpose of reducing costs or improving water quality.

Transfers
The Water Code defines a water transfer as a temporary or long-term change in the point of diversion, place of use, or purpose of use due to a transfer, sale, lease, or exchange of water or water rights. The City of Milpitas is not currently engaging in water transfers.

Emergency Interties
Emergency water interties are connections between water systems that allow for the exchange or delivery of water between those systems on a short-term emergency basis. Emergency interties are addressed in Section 7 Water Service Reliability and Drought Risk Assessment.

The City has one intertie with San Jose Water (SJW) and two interties with Alameda County Water District (ACWD) for emergency water supply. The SJW intertie is a 6 -inch line with a capacity of 2.6 million gallons per day (MGD). If a short -term or emergency supply were needed, the ACWD interties, both of which are eight inches, could each suffice to supply the City with approximately 2.3 MGD, equating to 4.6 MGD, which is nearly half of Milpitas’ pre-drought average day demand. If more interties were constructed and conn ected, it would be possible to purchase an even higher volumetric flow rate from ACWD.

City of Milpitas 2025 Urban Water Management Plan DRAFT 61

6.2.8 Supply From Storage
If a supplier removes water from either surface storage or underground storage (surface water) for use during the reporting year, the supplier should report this as a “supply from storage” in Tables 6-8 R and 6-9.

This section is not applicable to the City.

6.2.9 Future Water Projects
Per Water Code section 10631(f) this section describes all water supply projects and water supply programs that may be undertaken to meet the total projected water use. The City can meet future projected water needs from wholesale water purchases. However, as discussed earlier in Section 6. 1, the City completed a Source Capacity Analysis in 2022 as part of its Water Master Plan update , which recommended development of groundwater .

Table 6-7 summarizes the expected increase in water supply as a result of these projects.

Table 6-7. Expected Future Water Supply Projects or Programs Submittal Table 6-7 Retail: Expected Future Water Supply Projects - Water Code Section 10631 (f)  Check the box if there are no expected future water supply projects or programs that provide a quantifiable increase to the agency's water supply. Proceed to the next table.

Check the box if some or all of the supplier's future water supply projects or programs are not compatible with this table and are described in a narrative format. p. 61 Provide page location of narrative in the UWMP
Name of Future
Projects or
Programs
Joint
Project
with other
suppliers?
Additional Description
(as needed)
Planned
Implementation
Year
Planned for
Use in Year
Type
Expected
Increase in
Water
Supply to
Supplier
(MG)
Groundwater No
Three groundwater wells
(Pinewood, Curtis and
McCandless) pumping at 1.2
mgd as supply augmentation
to reduce dry year shortfall.
2030
Single-Dry
and Multi-
Dry Year
1,314
Groundwater No
One or more groundwater
wells pumping at 1.2 mgd as
supply augmentation to reduce
shortfall.
2035
Single-Dry
and Multi-
Dry Year
438
NOTES: 1. The three groundwater wells in this table that are shown online by year 2030 are currently for emergency use only and permitted to be operated no more than 5 consecutive days, and for no more than 15 calendar days per year. They pump at 1.2 MGD and are not designed as production supply wells. By year 2030, these groundwater wells will become an active non-emergency supply source and be able to operate at full production rate in dry year conditions.

2. By 2035, one or more additional wells pumping at 1.2 MGD or 438 MGY will be online yielding a total well capacity of 1,752 MGY for all groundwater wells. More than one well may be built between 2030 and 2035 depending on anticipated shortfall and well pumping capacities.

6.2.10 Summary of Existing and Planned Sources of Water Per Water Code Section 10631 this section will identify and quantify the existing and planned sources of water available over five-year increments and provide supporting and related information.

City of Milpitas 2025 Urban Water Management Plan DRAFT 62 Description of Supplies
The City’s existing water supplies include imported water, groundwater, recycled water, and interties with neighboring agencies. Under normal conditions, imported water comprises the City’s entire water supply. The City purchases treated surface water from two agencies: SFPUC and Valley Water, which was previously known as the Santa Clara Valley Water District. In 2025, water supplies from SFPUC totaled 1,929 MG and represented about 60% of the City’s total water supplies, while water supplies from Valley Water totaled 1,036 MG and represented about 32% of the City’s total water supplies. Recycled water is produced at the RWF and delivered to the City by SBWR. In 2 025, the City used approximately 273 MG of recycled water, mainly for landscape irrigation. This represented about 8 % of the City’s total 2025 water use. In emergencies, the City can activate interties with SJW and ACWD and/or pump groundwater. The City overlies the Santa Clara Valley Groundwater Sub-basin and currently has one groundwater well (Pinewood Well) permitted for emergency use.

Quantification of Supplies
Table 6-8 lists the actual volume of purchased or imported water for the City’s service area. Each supply source is listed and quantified separately. The City purchases its potable water supplies from SFPUC and Valley Water.

Under normal conditions, SFPUC and Valley Water supplies remain separate. Isolation valves prevent mixing and create two distinct water service areas. Recycled water is produced at the RWF and is delivered to the City by SBWR’s recycled water system.

Table 6-8. Water Supplies – 2025 Actual
Submittal Table 6-8 Retail: Water Supplies — 2025 Actual - Water Code Section 10631 (b) Water Supply Additional Description
2025
Water Type
(after treatment if
treated)
Actual Volume
(MG)
Purchased or Imported
Water
San Francisco Public Utilities
Commission Potable
1,929
Purchased or Imported
Water Valley Water Potable 1,036
Recycled Water South Bay Water Recycling Non-Potable 273 Subtotal Potable 2,965
Subtotal Non-Potable 273
Total 3,238
Table 6-9 lists the projected volume of water supplies, including volume by source, for the City’s service area.

City of Milpitas 2025 Urban Water Management Plan DRAFT 63 Table 6-9. Water Supplies – Projected
Submittal Table 6-9 Retail: Water Supplies — Projected - Water Code Section 10631 (b) Water Supply Additional Detail on Water
Supply
Water Type
(after treatment
if treated)
Projected Water Supply (Report to the Extent Practicable) 2030 2035 2040 2045 2050
Reasonably
Available
Volume
Reasonably
Available
Volume
Reasonably
Available
Volume
Reasonably
Available
Volume
Reasonably Available
Volume
(MG) (MG) (MG) (MG) (MG)
Purchased or Imported
Water SFPUC Potable 1,936 1,954 1,976 1,994 2,016
Purchased or Imported
Water Valley Water Potable 1,065 1,157 1,250 1,317 1,315 Recycled Water South Bay Water Recycling Non-Potable 275 275 275 280 280 Subtotal Potable 3,001 3,111 3,226 3,311 3,331
Subtotal Non-Potable 275 275 275 280 280
Total 3,276 3,386 3,501 3,591 3,611
NOTES: 1. SFPUC volume based on supplies provided to BAWSCA and SFPUC by the City of Milpitas in order to meet projected potable and nonpotable demands with no surplus or shortfall. Projected use reported in Table 4-2. Volumes provided by SFPUC in their March 12, 2026 documentation of the "Basis for SFPUC's Water Supply Reliability Modeling" and file 2025 UWMP Wholesale Customer Dry Year Allocations_FINAL.xls.

2. Valley Water supplies are equal to total normal year potable demands less SFPUC supplies. Assumes Valley Water's Water Supply Master Plan 2050 low- cost portfolio: Semitropic storage (350 thousand acre-feet [TAF]) through 2035; groundwater banking (250 TAF) starting 2040; Sisk Reservoir expansion in 2035; DCP in 2045; Pure Water Silicon Valley in 2035. Valley Water model period is 1922–2021.

3. Supplies meet Table 4-2 demands which include climate change as well as passive and active conservation.

City of Milpitas 2025 Urban Water Management Plan DRAFT 64

6.3 Energy Use
Water energy intensity is the total amount of energy, calculated on a whole-system basis, required for the use of a given amount of water in a specific location.33 The City used the Total Utility Approach for reporting energy intensity. This approach reports a single energy intensity for all water management operations. The energy intensity is reported for the calendar year. 2025 was selected as the one-year reporting period, and utility bills for the associated reporting period were used as the source for energy consumption data. Total energy consumed by City during calendar year 2025 based on reported utility bills is 704,489.71 kilowatt hour (kWh), excluding 860,313 kWh from solar. Based on the Total Utility Approach, the City’s energy intensity is estimated to be 217.6 (kilowatt hour per million gallons) kWh/MG.

The City also has calculated the energy associated with recycled water and with the collection and treatment of wastewater for the Calendar Year 2025 reporting period. Reported utility bills are used as the source for energy consumption data for the collection of wastewater. Energy use metered is used as the source for energy consumption data for wastewater treatment. Pumping volumes and energy associated with pumping is used as sources for data on recycled water. The City is not involved in the treatment o r final discharge of wastewater.

The City’s energy intensity for the collection of wastewater is estimated to be 312.49 (kilowatt hour per million gallons kWh/MG).

33 Wilkinson. (2000). Methodology for Analysis of the Energy Intensity of California’s Water Systems, supported by Ernest Orlando Lawrence Berkeley Laboratory and the California Institute for Energy Efficiency, accessed May 2026:
http://large.stanford.edu/courses/2012/ph240/spearrin1/docs/wilkinson.pdf

City of Milpitas 2025 Urban Water Management Plan DRAFT 65 7 WATER S YSTEM RELIABILIT Y
Lay Description
This chapter contains information about the City of Milpitas’s water service reliability and its Drought Risk Assessment (DRA). Assessing water service reliability is the fundamental purpose for water suppliers to prepare a UWMP. Water service reliability reflects the supplier’s ability to meet the water needs of its customers under varying conditions. This chapter integrates information from SFPUC, BAWSCA, Valley Water and the City about water reliability and planning for water shortages.

7.1 Introduction
This chapter incorporates information about its supply from SFPUC and Valley Water (described in Chapter 6) and its water uses (described in Chapter 4) and provides an evaluation of the City’s risk under a severe drought period lasting for five consecutive years (California Water Code Section 10635).

For its overall reliability assessment, the City uses current information from Valley Water, SFPUC and BAWSCA to assess its water service reliability under varying hydrologic and regulatory conditions. This analysis looks beyond the City’s past experience and considers what could be reasonably foreseen in the future.

The UWMP requires the City to develop a DRA that evaluates its risk under a severe drought period lasting for five consecutive years. The DRA is an important element for selecting the City’s Demand Management Measures (DMMs, Chapter 9) and for planning projects for a reliable water supply. The DRA is discussed in Section 7.3 and DMMs are discussed in Chapter 9 and the City’s WSCP (Appendix D).

In this chapter, the City also presents other water management measures in which the City has invested resources for long -term management and planning, such as the use of advanced technologies: advanced metering infrastructure (AMI), supervisory control and data acquisition (SCADA), and geographic information systems (GIS) for managing its water system and supplies effectively. Potential impacts from new development and climate change are long-term variables in the City’s supply planning.

The City incorporates the current information from SFPUC and BAWSCA34 to present its supply availability under the two contrasting scenarios provided by SFPUC: Scenario 1 – with the implementation of the 2018 amendments to the Bay-Delta Water Quality Control Plan and Scenario 2 – without the implementation of the Bay-Delta Plan. Using Scenario 1, the City presents its water supply and potential cutbacks – its water supply reliability – under the following hydrologic conditions:
• Normal hydrological conditions
• A single dry year
• Five consecutive years of drought
The analysis is conducted in 5-year increments to project what conditions may look like for the next 25 years.

In BAWSCA’s Dry Year Allocations tables for near-term single-year and multi-year droughts,35 the data are based on SFPUC’s guidance for Scenario 1 and Scenario 2 and forecast agency purchases for 2026 through 2030.

While it is not possible to predict specific future regulatory and development variables, to the extent they can be anticipated, they are discussed in this chapter.

34 Wilkinson. (2000). Methodology for Analysis of the Energy Intensity of California’s Water Systems, supported by Ernest Orlando Lawrence Berkeley Laboratory and the California Institute for Energy Efficiency, accessed May 2026:
http://large.stanford.edu/courses/2012/ph240/spearrin1/docs/wilkinson.pdf 35 BAWSCA Attachment B: 2025 UWMP Wholesale Customer Dry Year Allocations, BAWSCA, March 11, 2026. See Appendix E for more details.

City of Milpitas 2025 Urban Water Management Plan DRAFT 66

7.2 Water Service Reliability Assessment
Every Supplier is required to conduct a water service reliability assessment (WRSA) projection for a normal year, single dry year and five consecutive dry years.

Given that the City partially relies on supplies from SFPUC and Valley Water, a discussion about the potential impacts on SFPUC and Valley Water service reliability, due to the Bay -Delta Plan Amendment adoption, is warranted and presented below.

7.2.1 SFPUC system
In December 2018, the SWRCB adopted amendments to the Water Quality Control Plan for the San Francisco Bay/Sacramento-San Joaquin Delta Estuary (Bay -Delta Plan Amendment) to establish water quality objectives for the San Francisco Bay-Delta watershed. The SWRCB is required by law to regularly review this plan. The adopted Bay-Delta Plan Amendment was developed with the stated goal of increasing salmonid populations in three San Joaquin River tributaries (the Stanislaus, Merced, and Tuolumne Rivers) and the San Francisco Bay - Delta. The Bay-Delta Plan Amendment requires the release of 30 -50% of the “unimpaired flow” 36 on the three tributaries from February through June in every year type. In SFPUC modeling of the new flow standard, it is assumed that the required release is 40% of unimpaired flow. The Bay -Delta Plan amendment is discussed in further detail in Section 7.2.3.

As described in Chapter 6, the SFPUC RWS’s dominant supply is from the Tuolumne River watershed at high elevations in the Sierra Nevada Mountains. This main source of water for the SFPUC RWS is augmented by treated water produced by SFPUC from its local watersheds and facilities in Alameda and San Mateo counties.

In 2019, the SFPUC established the Alternative Water Supply (AWS) Program to identify and plan water supply and storage projects and actions that increase the dry -year reliability of the RWS. Based on the 2045 planning horizon that the SFPUC applied in its February 2024 AWS Plan, the SFPUC anticipates a water supply gap will occur in future dry years. The AWS Program aims to help fill the gap through local and regional capital projects.

Since the City’s water supply relies partially on the SFPUC RWS, impacts from the potential implementation of the Bay-Delta Plan, as presented in SFPUC’s Scenario 1, will impact the City’s service reliability. The City will be able to meet the projected water demands presented in this UWMP in normal years but would experience supply shortages in single dry years and multiple dry years. Implementation of the Bay-Delta Plan will require rationing in all single dry years and multiple dry years.

For the 2025 UWMPs, SFPUC provided two scenarios, using hydrologic models with and without the Bay-Delta Plan Amendment. BAWSCA, in turn, provided drought cutback allocations based on the information about projected water supply availability for the wholesale customers from SFPUC. All of BAWSCA’s allocation tables assume that wholesale customers can purchase up to 184 MGD from SFPUC’s RWS through 2050. Further details about the two scenarios can be found in Section 7.2.5 of this UWMP In normal years 100% of the City’s ISG is available to the City, that is 9.232 MGD. Assumptions from SFPUC about dry-year water supply projects are included in SFPUC’s Water System Improvement Program (WSIP) and considered in SFPUC’s Regional Water System supply reliability. 37 The SFPUC’s Regional Water System supply reliability data reflect SFPUC’s projected instream flow requirements under each scenario.

36 "Unimpaired flow represents the natural water production of a river basin, unaltered by upstream diversions, storage, or by export or import of water to or from other watersheds." Water Quality Control Plan for the San Francisco Bay/Sacramento-San Joaquin Delta Estuary (Dec. 12, 2018) p.17, fn. 14, available at https://www.waterboards.ca.gov/plans_policies/docs/2018wqcp.pdf . 37 SFPUC Regional Water System supply reliability letter from SFPUC, March 11, 2026 .

City of Milpitas 2025 Urban Water Management Plan DRAFT 67 The City’s expected water service reliability projections for a normal year, single dry year and five consecutive dry years are presented in the following tables:
• Table 7-1 presents the City’s water service reliability projections. • Table 7-2 shows a normal year supply and demand comparison through 2050. • Table 7-3 shows a single dry year supply and demand comparison through 2050. • Table 7-4 shows a multi-dry year supply and demand comparison through 2050. • Table 7 -5 is the DRA, showing a five -year Drought Risk Assessment to address Water Code Section 10635(b), for a multi-dry year supply and demand comparison from 2026 through 2030.

Table 7-1. Basis of Water Year Data (Reliability Assessment) OPTIONAL Submittal Table 7-1 Retail: Basis of Water Year Data (Reliability Assessment)

Check the box if quantification of available supplies is not compatible with this table and is provided elsewhere in the UWMP. Location: UWMP Section 7.2 and appendices D, E, and F Note that the City’s Tables 7 -2 through 7-4 extend to the year 205 0, beyond the requirement of 20 50 [Water Code Section 10635(a)].

7.2.2 Valley Water System
To maintain water supply reliability and flexibility, Valley Water ’s water supply includes a variety of sources including local groundwater, imported water, and local surface water. Valley Water has an active conjunctive water management program to optimize the use of groundwater and surface water, and to prevent groundwater overdraft and land subsidence.

Long-term planning and modeling analysis performed by Valley Water as part of its Integrated Water Resources Planning Study (IWRP) indicates that if additional investments are made, future countywide demands can reliably be met. It is the intent of Valley Water to invest in accordance with the IWRP framework to develop a flexible resource mix. This flexibility will allow Valley Water to respond to uncertain future conditions.

Valley Water’s first IWRP report, completed in 1997, identified alternative water resource strategies and ranked them against planning objectives that ultimately resulted in a final preferred strategy.

That strategy identified three programs corresponding to a range of future water shortage levels, with components phased in over time, based on demand.

The 2003 IWRP developed a planning framework and supporting modeling tools to help Valley Water identify and select specific water resource investments. The 2003 IWRP evaluation was based on a best estimate of the water demand and water supply outlook through 2040. Future water demand was estimated based on data from ABAG, California Department of Finance (DOF) and general plans from cities and Santa Clara County. The demand projection for the cities in Santa Clara County did not distinguish between Valley Water or SFPUC supplies.

The key findings from the 2003 IWRP are: (1) securing baseline supplies is top priority for ensuring reliability, 2) a mix of three types of new water supply investments makes the best water supply portfolio, and 3) local supplies decrease vulnerability; details on key findings from Valley Water’s 2003 IWRP document

38. 38 Valley Water (formerly Santa Clara Valley Water District), I ntegrated Water Resources Planning Study 2003, https://archive.org/details/csjvwd_000436.

City of Milpitas 2025 Urban Water Management Plan DRAFT 68

7.2.3 Service Reliability – Constraints on Water Sources To the extent practical, DWR requires retail suppliers to include information from their wholesale supplier about constraints on their water supply [Water Code section 10631 (b)(1)].

The amount of water available from SFPUC’s RWS and Valley Water ’s Agreement No. A0657 39 for a Supply of Treated Water for the City is constrained by climate, hydrology, facilities, and the institutional parameters that allocate the water supply from the Tuolumne River. Climate change may affect the snow-pack storage and water availability in future.

The recent changes to instream flow requirements for SFPUC and wholesale customer demand projections have affected SFPUC’s water supply planning. As a result, SFPUC established an Alternative Water Supply (AWS) Planning program in 2019 to evaluate several regional and local water supply options. The SFPUC published its AWS Plan in February 2024 and prepared a progress report on AWS projects in June 2025. The SFPUC plans to review and update the AWS Plan in 2027. Full details on SFPUC’s planned projects and actions can be found in SFPUC’s Alternative Water Supply Plan.

Constraints on SFPUC and Valley Water supplies were discussed in more detail in Chapters 3, 4, and 6. The main long-term constraints on supplies are due to climate change and regulatory changes. Key factors impacting water supply for both wholesalers include:
• Changes in precipitation patterns, such as time of snowfall or rain, intensity, and duration. • Changes in water quality because of changes in precipitation patterns and storage.

The constraints noted below will potentially affect SFPUC’s Hetch-Hetchy watershed and management of the RWS water supply and its distribution.
• Fewer months of continuous below freezing ( -32F) temperatures in the Sierra Nevada, resulting in less precipitation as snow, shorter duration for snowpack storage. • Warmer temperatures leading to melt of the snowpack storage. • Inadequate storage capacity to store the snowmelt water source. • Regulatory changes affecting SFPUC water supplies, such as implementation of the Bay -Delta Plan Amendment that could reduce supply water for the SFPUC RWS by 48% in drought years.

The constraints noted below will potentially affect Valley Water’s treated surface water and groundwater supply. • Groundwater availability.
• Regulatory changes impacting the State Water Project supply availability.

Potential Constraints on SFPUC’s RWS Supply – Bay-Delta Plan Amendment Updates As mentioned in Section 7.2.1 – SFPUC System , the SFPUC RWS’ supplies may be impacted by the implementation of the Bay-Delta Plan Amendment.

If the Bay -Delta Plan Amendment is implemented, SFPUC will be able to meet the projected water demands presented in its 2025 UWMP in normal years but is expected to experience supply shortages in single dry years or multiple dry years. Implementation of the Bay-Delta Plan Amendment could require rationing in all single dry years and multiple dry years. Given that the City partially relies on supplies from SFPUC, the City could also experience shortages.

Implementation of the Bay-Delta Plan Amendment remains uncertain for multiple reasons.

39 Agreement No. A0657 between the City and County of San Francisco and Santa Clara Valley Water District:
https://www.valleywater.org/sites/default/files/A0657_Agreement.pdf

City of Milpitas 2025 Urban Water Management Plan DRAFT 69 • Over a dozen lawsuits have been filed in both state and federal courts challenging the SWRCB’s adoption of the Bay -Delta Plan Amendment, including a legal challenge filed by the federal government at the request of the U.S. Department of Interior, Bureau o f Reclamation. This litigation is currently at the appellate level.
• The Bay -Delta Plan Amendment is not self -implementing and does not automatically allocate responsibility for meeting its new flow requirements to San Francisco or any other water rights holders.

The Bay-Delta Plan Amendment merely provides a regulatory framework for implementing water quality objectives, which must be accomplished by other regulatory and/or adjudicatory proceedings, such as a comprehensive water rights adjudication or, in the case of the Tuolumne River, may be implemented through the water quality certification process set forth in section 401 of the Clean Water Act as part of the Federal Energy Regulatory Commission’s licensing proceedings for the Don Pedro and La Grange hydroelectric projects. It is currently unclear when the license amend ment process is expected to be completed. This process and the other regulatory and/or adjudicatory proceedings may face legal challenges and have lengthy timelines, and quite possibly could result in a different assignment of flow responsibility (and therefore a different water supply impact on the RWS).

In recognition of the obstacles to implementation of the Bay-Delta Plan Amendment, the SWRCB Resolution No. 2018-0059 adopting the Bay -Delta Plan Amendment directed staff to help complete a “Delta watershed -wide agreement, including potential flow measures for the Tuolumne River,” and to incorporate such agreements as an “alternative” for a future amendment to the Bay -Delta Plan to be presented to the SWRCB “as early as possible after December 1, 2019.” On March 26, 2019, the SFPUC adopted Resolution No. 19 -0057 to support the SFPUC’s participation in the Voluntary Agreement negotiation process. To date, those negotiations are ongoing under the California Natural Resources Agency and the leadership of the Newsom administration. 40 On
November 10, 2022, the SFPUC along with the Modesto and Turlock Irrigation Districts signed a Memorandum of Understanding Advancing the Term Sheet for the Voluntary Agreements to Update and Implement the Bay - Delta Water Quality Control Plan
Because of the uncertainty surrounding implementation of the Bay -Delta Plan Amendment, the water service reliability assessment in the 2025 UWMP looks at two future supply scenarios: (1) implementation of the Bay - Delta Plan Amendment and (2) SFPUC system’s current conditions without implementation of the Bay-Delta Plan Amendment.

SFPUC Alternative Water Supply Planning Program41
In 2019, the SFPUC established the Alternative Water Supply (AWS) Program to identify and plan water supply and storage projects and actions that increase the dry -year reliability of the RWS. Based on the 2045 planning horizon that the SFPUC applied in its February 2024 AWS Plan, the SFPUC anticipates a water supply gap will occur in future dry years. The AWS Program aims to help fill the gap through local and regional capital projects.

The February 2024 AWS Plan identified six regional projects that might partially address the future water supply gap and the priorities for this planning effort. Since the development of that plan, three projects have been deferred (Daly City Recycled Water Expansion, Alameda County Water District -Union Sanitary District Purified Water, and Calaveras Reservoir Expansion) and one project has been canceled (Los Vaqueros Reservoir Expansion). SFPUC’s AWS Program is continuing to pursue the following two projects (see the program for full details on each project):
• PureWater Peninsula
• South Bay Purified Water

40 California Natural Resources Agency, “Voluntary Agreements to Improve Habitat and Flow in the Delta and its Watersheds,” available at https://files.resources.ca.gov/voluntary -agreements/. 41 Draft 2025 UWMP Common Language, BAWSCA, March 25, 2026.

City of Milpitas 2025 Urban Water Management Plan DRAFT 70 If both AWS projects that SFPUC staff has identified through the current planning process can be implemented, there would still be a supply shortfall to meet projected needs associated with implementation of the Bay-Delta Plan Amendment. Furthermore, both alternative water supply options are in the planning phase and are subject to changes in institutional structure and design. Given the limited availability of water supply alternatives, unless the supply risks are significantly reduced, the SFPUC will continue to plan, develop, and implement all potential projects that can help bridge the anticipated water supply gap during droughts.

Outside of the AWS Program, the following additional regional projects are included in the Agreements to Support Healthy Rivers and Landscapes discussed in the Bay-Delta Plan Amendment section above. Progress on these water supply options will be guided by scientific monitoring and collaborative decision making. • Groundwater Banking. Groundwater banking projects in the Modesto Irrigation District and Turlock Irrigation District service areas could provide the SFPUC with some additional water supply to meet instream flow releases in dry years, reducing water supply impacts on the RWS. A feasibility study of this option is included in the Agreements to Support Healthy Rivers and Landscapes within the AWS Plan. • Inter-Basin Collaborations. Inter-Basin Collaborations could include establishing a partnership between interests on the Tuolumne River (such as the SFPUC) and those on the Stanislaus River, which would allow responsibility for streamflow to be assigned variably based on the annual hydrology. • Dry-Year Transfers. The SFPUC initiated discussions with irrigation districts under WSIP to secure a dry- year transfer (see WSIP Dry-Year Water Supply Projects section below). While no transfer was secured, the SFPUC continues to engage in discussions with irrigation districts to explore potential transfer opportunities.

SFPUC’s AWS Plan published in February 2024 included a planning framework for SFPUC to consider water supply needs and related tradeoffs; guide the decisions to proceed with environmental review; and continue the development of projects that can best meet anticipated water supply needs. In June 2025, SFPUC prepared a progress report that provided status updates on the AWS projects. In 2027, SFPUC plans to review and revise its Alternative Water Supply Plan based on updated information.

SFPUC’s Water System Improvement Program (WSIP) Dry Year Water Supply Projects With WSIP, SFPUC has undertaken several water supply projects to meet dry -year demands. Those projects include the following:
• Calaveras Dam Replacement Project
• Alameda Creek Recapture Project
• Lower Crystal Springs Dam Improvements
• Regional Groundwater Storage and Recovery Project
• Regional Groundwater Treatment Improvements Project
• Water Transfers
Details of the projects can be found in the SFPUC 2025 UWMP.

City of Milpitas 2025 Urban Water Management Plan DRAFT 71 Constraints on the Valley Water System
The City’s water quality may also be affected if SFPUC’s sources of water change significantly. The City’s current water quality is characterized in its annual Water Quality Report.42 Specific expected changes will be identified when alternative water supplies are considered for implementation.

42 The City’s most recent Water Quality Reports can be found here: https://www.milpitas.gov/758/Water -Quality-Report.

Valley Water Standard Text
Groundwater
Constraints on groundwater:

Valley Water manages the Santa Clara and Llagas subbasins for the benefit of its groundwater customers and the county at large. Since the 1930s, Valley Water’s water supply strategy has been to maximize conjunctive use of surface water and groundwater supplies to enhance water supply reliability and avoid land subsidence. Local groundwater resources make up the foundation of the county’s water supply, but they need to be augmented by Valley Water’s comprehensive water management activities to reliably meet the needs of county residents, businesses, agriculture, and the environment. These activities include managed recharge of imported and local supplies and in-lieu groundwater recharge through the provision of treated surface water and raw water, acquisitio n of supplemental water supplies, and water conservation and recycling.

Groundwater supply is largely constrained by hydrologic variability and the estimated 548,000 AF of operational storage capacity within the subbasins. The inflows to the groundwater subbasins are constrained by Valley Water’s managed aquifer recharge program and natural recharge. Valley Water has about 144,000 AFY of managed recharge capacity, including about 98 miles of in-stream recharge and 102 off-stream recharge ponds. Maintaining Valley Water’s managed recharge program requires ongoing operational planning for the distribution of local and imported water to recharge facilities; maintenance and operation of reservoirs, diversion facilities, distribution systems, and recharge ponds; and the maintenance of water supply contracts, water rights, and relevant environmental clearance. Valley Water’s managed recharge program is critical to maintaining groundwater supply, because natural recharge is insufficient to meet groundwater demands. However, protecting natural recharge capacity is also important. Valley Water’s District Act and Board policy help preserve open space that supports agriculture and natural recharge capacity.

Groundwater quality can also be a constraint on groundwater supply. In general, the Santa Clara and Llagas subbasins have high-quality groundwater, except for nitrate, which is elevated in some wells in the Coyote Valley and Llagas Subbasin from historic and ongoing sources including fertilizers, septic systems, and animal waste. However, nitrate concentrations are generally stable or declining and Valley Water has many programs to protect groundwater quality, including several targeted to improve nitrate i n groundwater. Additional details about constraints on groundwater supply and quality and Valley Water’s comprehensive groundwater management strategies are described in the 2021 Groundwater Management Plan:
https://www.valleywater.org/your-water/where-your-water-comes- from/groundwater/sustainable-groundwater-management

City of Milpitas 2025 Urban Water Management Plan DRAFT 72

7.2.4 Year Type Characterization
Water Supply – All Year Types
SFPUC historically has met demand in its service area in all year types from its watersheds, which consist of:
• Tuolumne River watershed
• Alameda Creek watershed
• San Mateo County watersheds.

In general, 85 % of SFPUC supply comes from the Tuolumne River through Hetch Hetchy Reservoir and the remaining 15% comes from the local watersheds through the San Antonio, Calaveras, Crystal Springs, Pilarcitos and San Andreas Reservoirs. SFPUC’s adopted WSIP retains this mix of water supply for all year types.

Details about the projected projects and mix of water supply from SFPUC‘s watersheds can be found in the 2025 SFPUC UWMP.

Types of Years
DWR uses the terms normal and average interchangeably when addressing the water year type. DWR requires, as part of the water service reliability assessment in the DRA, that water suppliers include three types of years with specific hydrologic conditions. These include:

Normal Year. This condition represents the normal/average water supplies from SFPUC for BAWSCA agencies, and Valley Water for its water contractors . This condition represents the normal/average water supplies from SFPUC for BAWSCA agencies.

Single Dry Year. The single dry year represents the year with the lowest water supply available from SFPUC to the City.

Five-Consecutive-Year Drought. The five-consecutive year drought for the DRA is the driest five -year historical sequence for the water supply (Water Code Section 10612). For the water service reliability assessment, the City is using 2025 as its base year, because the City’s demand volume is based on the actual 202 5 purchases from SFPUC and Valley Water. As recommended by DWR, the City uses the same five-year sequence (2026–2030) for its water service reliability assessment. Note that SFPUC derived the fi ve-year consecutive drought based on the driest five- year sequence in the hydrologic record. This supply condition is a requirement of Water Code Section 10612. SFPUC has provided information about the likelihood of this severe condition in its 2025 UWMP.

Valley Water Standard Text
The greatest challenge to Valley Water’s water supply reliability is multiple dry years, such as those that occurred in 1988 through 1992 and in 2012 through 2016. The five dry-year period used in this analysis is 1988 to 1992, which was an extended drought within historic record and WEAP modeling period. The analysis indicates that with existing and planned projects’ supplies, Valley Water’s diverse water supplies are sufficient to meet demands throughout the full five-year drought in demand years 2035 and 2040 without having to call for short-term water use reductions, but in demand years 2030 as well as 2045 through 2050, there will be shortages in the last two years of the drought. The shortages are less than 10% of projected demands, thus within Valley Water’s level of service goal of meeting 100% of annual water demand during non-drought years and at least 80% of annual water demand in drought years.

Those shortages will be addressed through a combination of supply augmentation from transfer and exchange and water use reductions.

City of Milpitas 2025 Urban Water Management Plan DRAFT 73

7.2.5 Water Service Reliability Assessment
Every urban water supplier is required to include an assessment of its water service reliability to its customers through at le ast 2045, in five -year increments, during normal, dry, and multiple dry water years [Water Code Section 10635(a)].

Reliability of the SFPUC Regional Water System
Since the City purchases over 60% of its water from SFPUC , it is highly dependent on the SFPUC RWS infrastructure reliability.

Initiated in 2008, SFPUC’s Water System Improvement Program (WSIP) 43 is a $4.8 billion, multi- year capital program to upgrade the RWS as well as the SFPUC’s local water system. The program is delivering capital improvements that enhance the SFPUC’s ability to provide reliable, affordable, high quality drinking water in an environmentally sustainable manner to its Retail and Wholesale Customers. The SFPUC structured the WSIP to cost-effectively meet water quality requirements, improve seismic and delivery reliability goals through the year 2030, and fulfill water supply objectives. The SFPUC completed the San Francisco portion of WSIP in October 2020. As of June 30, 2025, the regional portion of WSIP was 99.3% complete, having repaired, replaced, and seismically upgraded crucial portions of the RWS; only two regional projects remain in planning and construction, while 49 regional projects have been completed or are in close -out. The SFPUC forecasts that the overall WSIP will be completed in June 2032.

The SFPUC undertook the WSIP to ensure the ability of the RWS to meet Level of Service (LOS) Goals and Objectives for water quality, seismic reliability, delivery reliability, and water supply. The Water Supply LOS goal, stated in the WSIP and adopted in 2008, is to meet customer water needs in non-drought and drought periods.

The SFPUC amended and updated the LOS Goals and Objectives in November 2023. The SFPUC’s current LOS Goals and Objectives related to water supply include the following:
• Meet an average annual water demand of 265 MGD from the SFPUC watersheds for Retail and Wholesale Customers during non -drought years consistent with the Water Supply Agreement (WSA) between San Francisco and its Wholesale Customers in Alameda, San Mateo, and Santa Clara Counties. • Meet dry -year delivery needs while limiting rationing to a maximum 20 % system-wide reduction in water service during extended droughts.
• Diversify and improve use of new water sources and drought management, including groundwater, recycled water, conservation, transfers, storage expansion, purified water, desalinated water, and technological innovations that can increase supply and/or water use efficiency.

In addition to SFPUC’s infrastructure reliability for the RWS, the imported water available to SFPUC’s retail and wholesale customers is constrained by climate, geology, hydrology, and the institutional parameters that allocate the water supply of the Tuolumne River. Due to these constraints, SFPUC is very dependent on reservoir and snow-pack storage to manage its water supplies. A summary of SFPUC’s vulnerability assessment related to climate change is included in Section 4.4.

These performance objectives serve as the basis for water supply planning by SFPUC for the RWS.

In planning for water service reliability during droughts , BAWSCA worked with SFPUC to develop a two t ier, drought allocation plan. The two tiers are discussed below.

43 SFPUC WSIP: https://www.sfpuc.gov/sites/default/files/documents/WSIPFiscalYear22- 23AnnualReport.pdf

City of Milpitas 2025 Urban Water Management Plan DRAFT 74 SFPUC’s Tier One Drought Allocations
The WSA44 between SFPUC and the Wholesale Customers is included in the references section of this UWMP, a Water Shortage Allocation Plan (WSAP), also known as the Tier 1 Shortage Plan. This plan describes the method for allocating water from the RWS between the SFPUC’s Retail Customers, on the one hand, and the Wholesale Customers collectively, on the other, during system-wide shortages caused by drought. The Tier 1 Shortage Plan applies only when the SFPUC determines that a system-wide water shortage due to drought exists, as set forth in a declaration of water shortage emergency by the SFPUC Commission; in the absence of such a declaration, the SFPUC also may opt to request voluntary cutbacks from its Retail and Wholesale Customers to achieve water use reductions. The SFPUC and the Wholesale Customers most recently amended the Tier 1 Shortage Plan in 2025.

SFPUC allocates water under the Tier 1 Shortage Plan
45 when it determines that the projected available water supply is less than projected system-wide water purchases for the upcoming Supply Year, defined as the period from July 1 through June 30. The following table shows the Retail Customers’ share and the W holesale Customers’ share of the annual water supply available during shortages depending on the level of system-wide reduction in water use that is required. If the SFPUC determines that the level of system-wide reduction required during a shortage is greater than 20%, SFPUC and the Wholesale Customers will meet to discuss the appropriate Retail and Wholesale Customers’ shares of available water. The Retail and Wholesale Customers’ shares of available water are also known as the Retail and Wholesale Custom ers’ Tier 1 Allocations. The Wholesale Customers’ Tier 1 Allocation will be apportioned among the individual Wholesale Customers based on a separate methodology, known as the Tier 2 Drought Response Implementation Plan (Tier 2 Plan), 46 which is separately
adopted by all the Wholesale Customers without the SFPUC’s involvement as discussed further below.

Figure 7-1. Share of Available Water – SFPUC and Wholesale Customers

The Tier 1 Shortage Plan allows for voluntary transfers of shortage allocations between the SFPUC and any Wholesale Customer as well as between Wholesale Customers themselves. In addition, voluntary transfers of water “banked” by the SFPUC or a Wholesale Customer, through reductions in usage greater than required, may occur.

Under the Tier 1 Shortage Plan, as amended in 2018, if the Retail Customers’ Tier 1 Allocation results in the Retail Customers receiving a “positive allocation” (i.e., a supply of additional water rather than a required reduction in water use), then the excess percentage for Retail is re-allocated to the Wholesale Customers’ Tier 1 Allocation.

44 City of Milpitas & City and County of San Francisco. (2021). Amended and Restated Water Supply Agreement. https://www.milpitas.gov/DocumentCenter/View/9998/2021-Amended-and-Restated-WSA-with-Attachments 45 Water Supply Agreement, Appendix I – Tier 1 Water Shortage Allocation Plan. https://www.calwater.com/wp- content/uploads/2025/01/Appendix_I_-_SF_WSA-1.pdf
46 Tier 2 Drought Response Implementation Plan (Tier 2 Plan). https://milpitasca.portal.civicclerk.com/event/2048/files/attachment/1456

City of Milpitas 2025 Urban Water Management Plan DRAFT 75 The Retail Customers are also required to conserve a minimum of 5% for any level of reduction in system -wide water use. The additional water conserved by Retail Customers up to the minimum 5% level is deemed as remaining in RWS storage for inclusion in the calculation of projected available water in future successive dry years.

The Tier 1 Shortage Plan will expire at the end of the WSA in 2034, unless the SFPUC and the Wholesale Customers mutually agree to revise or terminate it prior to that date.

BAWSCA’s Tier Two Drought Allocations
The BAWSCA member agencies have negotiated and adopted the Tier 2 Plan, referenced above, which allocates the Wholesale Customer Tier 1 Allocation from the Tier 1 Shortage Plan among each of the 26 Wholesale Customers. These Tier 2 Allocations are based on a formula that takes into account multiple factors for each Wholesale Customer including:
• Residential population;
• Non-residential “base” (i.e., indoor) use;
• Seasonal uses;
• Total RWS purchases in recent non-drought years; and
• Individual Supply Guarantee;
The Tier 2 Plan employs a structured, sequential, five -step method to allocate water to each Wholesale Customer. The allocations are constrained by minimum and maximum cutbacks, which establish the maximum final allocation and minimum guaranteed final allo cation, respectively. No agency's final allocation can fall outside of these bounds. The allocation then proceeds by prioritizing indoor uses.

The subsequent steps systematically allocate the remaining available water based on different customer demands. First focusing on indoor demand, water is allocated based on an agency’s residential population and the State residential efficient indoor stand ard (47 gallons per capita per day (GPCD) in 2025), followed by an allocation based on non -residential “base” (i.e., indoor) use. A limited amount of water is allocated based on seasonal use (e.g., cooling towers and irrigation). Finally, the remaining supply is allocated based on a weighted share of two-thirds RWS purchases in the recent non-drought years and one-third ISG.

The result of the Tier 2 Plan is each Wholesale Customers’ proportion, expressed as a percentage, of the available Tier 1 Allocation (Allocation Factor).

The Tier 2 Plan requires that the Allocation Factors be calculated by BAWSCA each year in preparation for a potential water shortage emergency. As the Wholesale Customers change their water use characteristics (e.g., increases or decreases in RWS purchases and use of other water sources, changes in monthly water use patterns, or changes in population), the Allocation Factor for each Wholesale Customer will also change. However, for long-term planning purposes, each Wholesale Customer may use as its Allocation Factor, the value identified in the Tier 2 Plan when adopted.

The Tier 2 Plan was renegotiated and adopted by all Wholesale Customers in 2025.

Additional BAWSCA Efforts to Facilitate Water Supply Reliability BAWSCA, on behalf of its member agencies, facilitate s local projects that augment water supply reliability.

BAWSCA’s key water management objective is to ensure that a reliable, high-quality supply of water is available where and when people within the BAWSCA service area need it. A reliable supply of water is required to support the health, safety, employment, and economic opportunities of the existing and expected future residents in the BAWSCA service area and to supply water to the agencies, businesses, and organizations that serve those communities.

City of Milpitas 2025 Urban Water Management Plan DRAFT 76 In 2018, BAWSCA began working with SFPUC to amend the 2009 WSA between SFPUC and BAWSCA’s member agencies, which included requirements for SFPUC to formally engage with BAWSCA during SFPUC’s development of its 10-year capital improvement program (CIP). The updated and restated WSA (also termed the 2019 WSA) was executed by SFPUC and BAWSCA’s member agencies in August 2019. 47 Subsequent amendments were made to the WSA, resulting in a 2021 WSA and the current 2025 WSA.

In December 2025, BAWSCA completed its Demand Study that presents updated information about the BAWSCA service area demands and demand management as part of its strategy for a long -term reliable supply. The Demand Study identifies demand management measures for the commercial, irrigation, and residential sectors, and system water loss management.

BAWSCA Updated 2025 UWMP Drought Cutbacks based on SFPUC March 2026 Water Supply Reliability As discussed in earlier chapters, BAWSCA’s role in representing the interests of its 26 member agencies is to work with SFPUC to ensure that SFPUC meets its contractual obligations to maintain its infrastructure and provide a reliable, high quality, potable water supply at a fair price.

The updated drought cutback allocations that BAWSCA developed for the 2025 UWMPs are based on SFPUC’s Scenario 1 and Scenario 2 (see Appendix E of this UWMP ). BAWSCA’s drought allocation cutback calculations use SFPUC Regional Water System supply reliability models under extreme hydrologic conditions and on actual historic supply.

Note that SFPUC derived the five- year consecutive drought based on the driest five -year sequence in the hydrologic record. This supply condition is a requirement of Water Code Section 10612 . SFPUC has provided information about the likelihood of this severe condition in the SFPUC 2025 UWMP. 48 Individual Supply Guarantee
SFPUC has a perpetual commitment (Supply Assurance) to deliver 184 MGD to its 24 permanent Wholesale Customers collectively. San Jose and Santa Clara are not included in the Supply Assurance commitment and each has temporary and interruptible water supply contracts with SFPUC. The Supply Assurance is allocated among the 24 permanent Wholesale Customers through an Individual Supply Guarantee (ISG), which represent each Wholesale Customer’s allocation of the 184 MGD Supply Assurance.

The City of Milpitas’s ISG is 9.232 MGD
The City’s ISG is of critical importance to its current and future customers for long-term vitality of its community, economy, and security.

SFPUC’s Water Supply Reliability Evaluation
49 In general, 85 % of the RWS supply comes from the Tuolumne River through Hetch Hetchy Reservoir and the remaining 15% comes from the local watersheds through the San Antonio, Calaveras, Crystal Springs, Pilarcitos and San Andreas Reservoirs. The adopted Water System Improvement Program (WSIP) retains this mix of water supply for all year types.

To evaluate its supply reliability, SFPUC closely monitors the hydrologic conditions impacting its watersheds in the Sierras and the San Francisco Bay Area. Based on hydrologic conditions, SFPUC routinely provides updates about its water supply that may impact water supply for BAWSCA agencies. Annual weather trends and long-

47 BAWSCA Capital Improvement Planning Comparison Study, September 2019, page 1. http://bawsca.org/uploads/userfiles/files/CIP%20Comparison%20Study%20_09 -2019_V_Final_9_10_19.pdf 48 SFPUC, April 2026, Likelihood of a five-year drought sequence as provided in their UWMP. 49 2025 UWMP SFPUC Common Language March 25, 2026.

City of Milpitas 2025 Urban Water Management Plan DRAFT 77 term impacts from a changing climate are part of SFPUC’s on -going analyses and are included in long -term planning for a reliable RWS water supply.

Unlike previous SFPUC water supply reliability forecasts that were mostly based on hydrologic conditions and projects that impacted infrastructure , in March 2026 SFPUC provided BAWSCA with two forecasts (Scenario 1 and Scenario 2) for the reliability of its water supply. The 202 5 SFPUC water supply reliability evaluation incorporates potential extreme impacts to its RWS supply from regulatory changes due to the Bay -Delta Plan Amendment (Bay-Delta Plan) as well as a reference comparison with the current supply regime.50 The Bay-Delta Plan Amendment requires the release of 30 -50% of the “unimpaired flow” 51 on the three tributaries from February through June in every year type. In SFPUC modeling of the new flow standard, it is assumed that the required release is 40% of unimpaired flow. As a result, SFPUC has established an Alternative Water Supply Planning (AWS) program to evaluate several regional and local water supply options ; the AWS program is discussed in further detail in Section 7.2.3 and in SFPUC’s UWMP; The implementation of the Bay-Delta Plan is uncertain for multiple reasons that are presented in Section 7.2.3, Service Reliability – Constraints on Water Sources. Because of the uncertainty surrounding impl ementation of the Bay-Delta Plan Amendment, the water service reliability assessment in the 2025 UWMP looks at two future supply scenarios: (1) with implementation of the Bay -Delta Plan Amendment and (2) SFPUC system’s current conditions without implementation of the Bay-Delta Plan Amendment.

For the 2025 UWMPs, agencies are required to develop a Drought Risk Assessment (DRA) that assumes a single year and multiple years of drought, starting with 2026 through 2030. SFPUC provided tables with its forecast for Scenario 1 and 2 that provide specific water supply data to address the DRA.

For drought planning for SFPUC wholesale water shortages of less than 20 %, SFPUC and BAWSCA have developed the Tier One Plan to allocate shortages between SFPUC and the Wholesale Customers collectively.

BAWSCA utilizes the Tier Two plan to allocated available water supplies to the wholesale agencies. However, the BAWSCA Tier Two plan was not intended for shortages of more than 20%. Therefore, for the shortage scenarios and assumptions in SFPUC’s Scenario 1 “with Bay-Delta Plan Amendment” that reduce water use in dry years by almost 48% for its wholesale customers, BAWSCA recommended an alternate method to apply drought cutbacks equally among BAWSCA agencies.
52 Information Sources for Projected SFPUC RWS and Wholesale Purchases SFPUC s upply provides its projected supply availability and reliability based on hydrologic conditions and modeling, and regulatory and infrastructure constraints. wholesale supply allocations are based on projected BAWSCA wholesale purchases provided by BAWSCA member agencies. Active conservation by BAWSCA agencies is treated as a source of supply by BAWSCA, therefore projected wholesale purchases are after passive and active conservation.

50 Bay-Delta Plan Update: Amendments and Substitute Environmental Document (SED) for lower San Joaquin River and Southern Delta– Adoption and approval of plan amendments and final SED. https://www.waterboards.ca.gov/waterrights/water_issues/programs/bay_delta/bay_delta_plan/water_quality_control_ planning/2018_sed/
51 "Unimpaired flow represents the natural water production of a river basin, unaltered by upstream diversions, storage, or by export or import of water to or from other watersheds." (Water Quality Control Plan for the San Francisco Bay/Sacramento-San Joaquin Delta Estuary (Dec. 12, 2018) p.17, fn. 14, available at https://www.waterboards.ca.gov/plans_policies/docs/2018wqcp.pdf .) 52 BAWSCA Attachment B: 2025 UWMP Wholesale Customer Dry Year Allocations, BAWSCA, March 11, 2026.

City of Milpitas 2025 Urban Water Management Plan DRAFT 78 Following the completion of BAWSCA’s Demand Study in December 2025,53 BAWSCA used the results to develop a table for each member agency listing possible supplies and total demand for 2030, 2035, 2040, 2045, and 2050.

BAWSCA populated the tables with total water demand after passive conservation and entered active conservation, as calculated in each agency’s analysis.

Each year agencies are offered the opportunity to review and, if needed, revise their purchase forecasts in January. BAWSCA Agencies have provided BAWSCA with similar updates to projected purchases annually for the past 10 years. On March 4, 2026, BAWSCA transmitted agency purchase requests for SFPUC’s use in their 202 5 UWMP. This annual reporting is part of SFPUC’s wholesale rate setting process.

Key Findings of the Water Service Reliability Analysis
BAWSCA/SFPUC Reliability
The results of the current water reliability assessment affect the City’s short- and long-term water management decisions. The City is working with BAWSCA and its member agencies to identify regional mitigation measures to improve reliability for regional and local water supplies and meet its customers’ water needs.

If conditions for large drought cutbacks to BAWSCA wholesale agencies persist, such as those presented by SFPUC in Scenario 1, the City will need to implement additional demand management practices to invoke strict restrictions on potable water use and obtain funding to accelerate developing alternate supplies of water.

Due to the continued uncertainty for SFPUC water supply during droughts and impacts from the implementation of the Bay-Delta Plan on its water supply reliability, in its 2025 UWMP, the City presents information for water supply reliability using SFPUC Scenario 1, with the Bay-Delta Plan.

SFPUC is continuing negotiations with the California State Water Board on implementation of the Bay-Delta Plan for water supply cutbacks, particularly during droughts. SFPUC is developing a collaborative approach to protect the environment and plan for a reliable and high-quality future potable water supply. This is a dynamic situation and drought cutback allocations may need to be revised before the City’s 2030 UWMP.

With this uncertainty, the City could update its DRA (see Section 7.3) prior to the 2030 UWMP update if significant new information becomes available. The Water Code Section 10635(b) permits urban water suppliers to conduct an interim update or updates to their DRA within the five- year cycle of its UWMP update. The City anticipates that by the 2030 UWMP update, SFPUC will provide more specific information about the Alternative Water Supply Planning Program, with estimated water supply contributions from such projects. Additionally, the City expects that SFPUC will provide more specific information and a refined estimate of the Bay -Delta Plan impacts to SFPUC supply.

The City recommends that users of its 2025 UWMP contact City staff for potential updates about the City’s water supply reliability and its DRA before using the 202 5 UWMP drought cutback projections for their planning projects and referencing the drought allocations.

53 Demand Study:
https://bawsca.org/uploads/userfiles/files/2025%20BAWSCA%20Demand%20Study_Final%20Report%20%2B%20Appendi ces_submittal%281%29.pdf

City of Milpitas 2025 Urban Water Management Plan DRAFT 79 Valley Water’s Water Supply Reliability Evaluation
Valley Water Standard Text
Demand and Supply Assessment
Valley Water maintains diverse water supply sources to meet countywide demands. Major sources of supply for Valley Water include natural groundwater recharge, local surface water, imported water from the State and Federal projects, and recycled and purified water. In addition, the SFPUC delivers water to eight retailers in the northern part of Santa Clara County. Below is a summary of the constraints to Valley Water’s water supply sources.

Imported water – Valley Water’s SWP and CVP water supplies are subject to hydrologic variability and several additional constraints including regulatory constraints, seismic threats to the Delta levee system, sea level rise , climate change, and water quality variations.

Groundwater – The groundwater supply is largely constrained by hydrologic variability and the estimated operational storage capacity within the subbasins. The inflows to the groundwater subbasins are constrained by Valley Water’s managed aquifer recharge program and natural recharge. Groundwater quality can also be a constraint on groundwater supply.

Local surface water – Local surface water supplies are vulnerable to hydrologic variability and constrained by environmental regulations and permit requirements. Climate change may cause decreases in the ability to utilize local surface water supplies.

Recycled and Purified Water – The constraints on future recycled water deliveries include infrastructure capacity and the availability of recycled water. Some of the potential constraints on the development of potable reuse include reverse osmosis concentrate disposal, public acceptance, permitting, hydrogeologic conditions, wastewater availability from other agencies (Valley Water is not a wastewater agency), and cost.

Water Service Reliability
Valley Water’s water service reliability was assessed by compar ing supplies and demands under three hydrologic conditions – an average year, a single dry year, and five consecutive dry year s. Valley Water uses the Water Evaluation and Planning (WEAP) model to evaluate water supply reliability under these conditions. Developed by the Stockholm Environment Institute, WEAP is a deterministic, integrated water resources management model that uses water demand and supply information and account s for multiple and competing uses and priorities. Valley Water uses the WEAP model as a tool to support its long-term water supply planning. The WEAP model simulates Valley Water’s water supply system comprised of facilities to recharge the county’s groundwater subbasins, operation of reservoirs and creeks, treatment and distribution facilities, and raw water conveyance facilities . The model also accounts for non-Valley Water sources and distribution, such as supplies from the SFPUC, non-potable recycled water, and local water developed by other agencies, such as the San Jose Water Company. In essence, the model was formulated to simulate the management of the current and future water resources within the county.

Valley Water’s WEAP water supply planning model operates on a monthly time -step that simulates the water supply and demand over 100 years, using the historic hydrologic sequence of 1922 through 2021. The model tracks water resources throughout the county and delivery of water to meet demands according to availability and priority. Water supply reliability assessment for average year, a single dry year, and five consecutive dry year conditions was based on the model results under each condition.

Average Year Supply Reliability
Valley Water uses the average annual supply over the 100 modeled years to represent the average year condition.

Under average conditions, Valley Water’s projected water supplies exceed projected demand through 2050 in all demand years.

City of Milpitas 2025 Urban Water Management Plan DRAFT 80 City of Milpitas Service Reliability
The City’s water service reliability assessment is based on historic and current information about water use in its service area, SFPUC’s RWS water sources and SFPUC’s water supply reliability and Valley Water Sources and Valley Water’s water supply reliability . In its assessment, the City also includes impacts from c limate change projections.

The City’s Tables 7 -2, 7-3, and 7-4 summarize the water supply reliability for a normal (average) year, a single dry year, and five- consecutive dry years for 2030, 2035, 2040, 2045, and 2050.

Summary information and location of details are also included with the tables (notes).

In its reliability assessment, the City considers:
• The potential for acquiring supplemental water supplies. • The potential for increased demands due to increased irrigation use due to low rainfall. • Expected demand reduction due to increased implementation of demand management measures.

Valley Water Standard Text (cont.)
Single Dry Year Supply Reliability
The single driest year in the 100 model years occurred in 1977, based on the historic hydrological record.

With supply from storage, supplies are sufficient to meet demands during a single dry year through 2050.

This assumes that reserves are at healthy levels at the beginning of the year and that the projects and programs identified in Valley Water’s Water Supply Master Plan (WSMP) 2050 are implemented. Supplies available for this single year drought represent water needed not only for that single drought year, but also water that may be needed for a prolonged drought. Valley Water would manage the supplies re ported in this table assuming the drought may continue beyond a single year, and thus not all supplies are expected to be used by retailers during the single year drought.

Multiple Dry Year Supply Reliability
The greatest challenge to Valley Water’s water supply reliability is multiple dry years, such as those that occurred in 1988 through 1992 and in 2012 through 2016. The five dry-year period used in this analysis is 1988 to 1992, which was an extended drought within historic record and WEAP modeling period . The analysis indicates that with existing and planned projects’ supplies, Valley Water’s diverse water supplies are sufficient to meet demands throughout the full five-year drought demand years 2035 and 2040 without having to call for short-term water use reductions, but in demand years 2030 as well as 2045 through 2050, there will be shortages in the last two years of the drought. The shortages are less than 10% of projected demands, thus within Valley Water’s level of service goal of meeting 100% of annual water demand during non-drought years and at least 80% of annual water demand in drought years. Those shortages will be addressed through a combination of supply augmentation from transfer and exchange a nd water use reductions.

Valley Water’s basic water supply strategy to compensate for supply variability is to store excess wet year supplies in the groundwater basin, local reservoirs, San Luis Reservoir, and/ or Semitropic Groundwater Bank, and draw on these reserve supplies during dry years to help meet demands. These reserves , along with existing and planned future projects in the WSMP, help Valley Water meet demands during a prolonged drought. Future projects and programs recommended in the WSMP 2050, including additional long-term water conservation savings, potable reuse, recharge capacity increases, and banking and storage, were developed in accordance with this policy to minimize the need to call for water use reductions greater than 20%.

City of Milpitas 2025 Urban Water Management Plan DRAFT 81 • Implementation of its updated 2025 WSCP.
• Savings from local ordinances and standards.
• Increased drought messaging.

In Section 7.2. 7, Description of Management Tools and Options, the City discusses potential management actions that it may take in response to SFPUC shortages. Table 7-6, in Section 7.3.3, shows projected shortages of SFPUC supply compared with the City’s projected demand.

DWR’s Optional Planning Tool
DWR provided an optional Planning Tool Worksheet for 2025 UWMP preparation. DWR’s optional Planning Tool was introduced earlier in Chapter 4.

The City is not using the Planning Tool , instead the City is using information from SFPUC, BAWSCA, and its demand projections from the BAWSCA Demand Study . The City ’s planning for drought cutbacks includes historical, current, and forecasts about water use, water sector growth, population, jobs, and conservation.

7.2.6 WSRA Supply and Demand Comparison
The WSRA combines the details of the City’s water -use analysis in Chapter 4 and their water supply analysis in Chapter 6. A comparison of supplies and demands provides the City with a complete picture of both their short- term and long-term water service reliability.

Water Service Reliability – Normal Year
In Table 7-2, DWR requests suppliers to provide their normal year supply and demand for comparison, in five - year increments through at least 2045. The normal year supply for BAWSCA agencies is 100% of SFPUC’s Supply Agreement, that is 184 MGD. Therefore, in Table 7 -2, under the City’s normal SFPUC supply is 100% of its ISG, that is 9.232 MGD. SFPUC normal year supply will meet the City’s projected demands for 2030, 2035, 2040, 2045, and 2050. Table 7-2 supply totals are based on table 6-9 and present projected SFPUC purchases, Valley Water supplies, and recycled water supplies.

Table 7-2. Normal Year Supply and Use Comparison
Submittal Table 7-2 Retail: Normal Year Supply and Use Comparison - Water Code Section 10635 (a) 2030 2035 2040 2045 2050
(MG) (MG) (MG) (MG) (MG)
Supply totals
(autofill from Submittal Table 6-9 R) 3,276 3,386 3,501 3,591 3,611 Use totals
(autofill from Submittal Table 4-2 R) 3,276 3,386 3,501 3,591 3,611 Surplus/(shortfall) 0 0 0 0 0
Water Service Reliability – Single Dry Year
In Table 7-3, DWR requests suppliers to provide their single dry year supply and demand for comparison, in five- year increments through at least 2045. In this table, the City includes its supply reliability using SFPUC scenarios, with Bay -Delta Plan for a single dry year through 2050 . The City is using SFPUC ’s “2025 UWMP Wholesale Customer Dry Year Allocations ,” dated, March 11, 2026, based on SFPUC’s Regional Water Supply Reliability letter (see Appendix E), which was also released on March 11, 2026, for 1 st dry year allocation with Bay -Delta Plan.

As can be seen in Table 7-3, with Bay-Delta Plan for a single dry year Supply and Demand Comparison, the City will experience significant water s upply cutbacks with SFPUC supply. These SFPUC supply shortfalls will invoke

City of Milpitas 2025 Urban Water Management Plan DRAFT 82 the City ’s WSCP , and t he City will have to work closely with its customers . Supply augmentation and water demand reduction measures for all levels of the City’s WSCP are discussed in the WSCP (see Appendix D of this UWMP).

The City submitted Table 7 -3, with Bay -Delta Plan, in the WUE portal to comply with the 202 5 UWMP requirements and to be consistent with its supplier, SFPUC.

Table 7-3. Single Dry Year Supply and Demand Comparison, with Bay-Delta Plan Submittal Table 7-3 Retail: Single Dry Year Supply and Use Comparison - Water Code Section 10635(a) 2030 2035 2040 2045 2050
(MG) (MG) (MG) (MG) (MG)
Supply totals 2,672 2,740 2,805 2,855 2,836
Use totals 3,276 3,386 3,501 3,591 3,611
Surplus/(shortfall) (604) (646) (696) (736) (775)
OPTIONAL Planned WSCP Actions
WSCP - use reduction savings benefit 604 646 696 736 775 Revised Surplus/(shortfall) 0 0 0 0 0
NOTES: 1. Supply and use include both potable water and recycled water.

2. Single dry year use expected to align with Table 4-2 projected normal year water use, for potable and non-potable. Table 4-2 projected use includes climate change as well as passive and active conservation.

3. Non-potable supply totals based on projected recycled supplies meeting recycled water demands.

4. Potable supply totals include Valley Water and SFPUC delivered supplies.

5. SFPUC potable water supplies based on projected supply by year and year type per "2025 UWMP Wholesale Customer Dry Year Allocations_FINAL.xlsx", WITH implementation of the 2018 amendments to the Bay-Delta Water Quality Control Plan (Bay-Delta Plan Amendment).

6. Valley Water single dry year supplies align with Valley Water normal year supplies with no reduction (or increase) in Valley Water potable water supplies expected in a single dry year. Assumes Valley Water's Water Supply Master Plan 2050 low-cost portfolio: Semitropic storage (350 TAF) through 2035; groundwater banking (250 TAF) starting 2040; Sisk Reservoir expansion in 2035; DCP in 2045; Pure Water Silicon Valley in 2035. Valley Water model period is 1922–2021; single dry year is 1977. Reasonably available supply is water in storage above thresholds for emergency needs, subsidence protection, and operational withdrawal limits for each storage facility.

7. Shortfall to be preliminarily addressed with WSCP use reduction actions as reported in Table 8-3. Stage 2 and 3 drought response actions would yield the anticipated 15%-25% use reduction estimated.

8. WSCP supply augmentation benefits as reported in Table 8-2 and including groundwater production will be implemented if necessary.

Water Service Reliability – Five Consecutive Dry Years
In Table 7-4, DWR requests suppliers to provide their multiple dry years supply and demand comparison multi- dry year (five) consecutive supply and demand for comparison, from 2030 through at least 2045.

In Table 7-4, the City includes its supply reliability using SFPUC scenarios with Bay-Delta Plan for five multiple dry years (starting in 2030, 2035, 2040, 2045, and 2050). The City is using SFPUC’s “2025 UWMP Wholesale Customer Dry Year Allocations”, dated, March 11, 2026, based on SFPUC’s Regional Water Supply Reliability letter, which was also released on March 11, 2026 for 1st, 2nd, 3rd, 4th, and 5th dry year allocations with Bay-Delta Plan.

City of Milpitas 2025 Urban Water Management Plan DRAFT 83 Note that SFPUC derived the five- year consecutive drought based on the driest five -year sequence in the hydrologic record. This supply condition is a requirement of Water Code Section 10612. SFPUC has provided information about the likelihood of this severe condition in 2025 SFPUC UWMP.

As can be seen in Table 7 -4, with Bay-Delta Plan, for multiple dry years supply and demand comparison, from 2030 through 2050, the City will experience significant water supply cutbacks.

Table 7-4. Multiple Dry Years Supply and Use Comparison, with Bay-Delta Plan Submittal Table 7-4 Retail: Multiple Dry Years Supply and Use Comparison - Water Code Section 10635(a) 2030 2035 2040 2045 2050
(MG) (MG) (MG) (MG) (MG)
First
year
Supply totals 2,673 2,741 2,806 2,856 2,837
Use totals 3,276 3,386 3,501 3,591 3,611
Surplus/(shortfall) (603) (645) (695) (735) (774)
OPTIONAL Planned WSCP Actions
WSCP - use reduction savings benefit 603 645 695 735 774 Revised Surplus/(shortfall) 0 0 0 0 0
Second
year
Supply totals 2,459 2,547 2,610 2,658 2,636
Use totals 3,276 3,386 3,501 3,591 3,611
Surplus/(shortfall) (817) (839) (891) (933) (975)
OPTIONAL WSCP Actions
WSCP - use reduction savings benefit 817 839 891 933 975 Revised Surplus/(shortfall) 0 0 0 0 0
Third
year
Supply totals 2,459 2,547 2,610 2,658 2,636
Use totals 3,276 3,386 3,501 3,591 3,611
Surplus/(shortfall) (817) (839) (891) (933) (975)
OPTIONAL Planned WSCP Actions
WSCP - use reduction savings benefit 817 839 891 933 975 Revised Surplus/(shortfall) 0 0 0 0 0
Fourth
year
Supply totals 2,406 2,547 2,610 2,592 2,570
Use totals 3,276 3,386 3,501 3,591 3,611
Surplus/(shortfall) (870) (839) (891) (999) (1,041)
OPTIONAL Planned WSCP Actions
WSCP - use reduction savings benefit 870 839 891 999 1,041 Revised Surplus/(shortfall) 0 0 0 0 0
Fifth
year
Supply totals 2,406 2,547 2,610 2,592 2,570
Use totals 3,276 3,386 3,501 3,591 3,611
Surplus/(shortfall) (870) (839) (891) (999) (1,041)
OPTIONAL Planned WSCP Actions
WSCP - use reduction savings benefit 870 839 891 999 1,041 Revised Surplus/(shortfall) 0 0 0 0 0

City of Milpitas 2025 Urban Water Management Plan DRAFT 84 Submittal Table 7-4 Retail: Multiple Dry Years Supply and Use Comparison - Water Code Section 10635(a) NOTES for Table 7-4:

1. Supply and use include both potable water and recycled water.

2. Multiple dry year use expected to align with Table 4-2 projected normal year water use, for potable and non- potable. Table 4-2 projected use includes climate change as well as passive and active conservation.

3. Non-potable supply totals based on projected recycled supplies meeting recycled water demands.

4. Potable supply totals include Valley Water and SFPUC delivered supplies.

5. SFPUC potable water supplies based on projected supply by year and year type per "2025 UWMP Wholesale Customer Dry Year Allocations_FINAL.xlsx", WITH implementation of the 2018 amendments to the Bay-Delta Water Quality Control Plan (Bay-Delta Plan Amendment).

6. Valley Water multiple dry year supplies align with Valley Water normal year supplies with an additional reduction of 5% in Valley Water potable water supplies expected in a multiple dry years 4 and 5 in multiple dry years starting in 2030, 2045 and 2050. Valley Water supplies are based on their Water Supply Master Plan 2050 low-cost portfolio: Semitropic storage (350 TAF) through 2035; groundwater banking (250 TAF) starting 2040; Sisk Reservoir expansion in 2035; DCP in 2045; Pure Water Silicon Valley in 2035. Valley Water model multi-year drought is 1988–1992; this remains the most severe extended drought in the record. Reasonably available supply is water in storage above thresholds for emergency needs, subsidence protection, and operational withdrawal limits for each storage facility.

7. Shortfall to be preliminarily addressed with WSCP use reduction actions as reported in Table 8-3. Stage 2 and 3 drought response actions would yield the anticipated 15%-30% use reduction estimated.

8. WSCP supply augmentation benefits as reported in Table 8-2 and including groundwater production will be implemented if necessary.

The reduction measures for all level s of the City’s WSCP are discuss ed in the WSCP (see Appendix D of this UWMP).

DWR requires that suppliers only use one scenario to input data into the Water Use Efficiency Data (WUE) portal.

The City submitted Table 7 -4, with Bay -Delta Plan in the WUE portal to comply with the 2025 UWMP requirements and to be consistent with its supplier, SFPUC.

7.2.7 Description of Management Tools and Options
According to Water Code Section 10620(f), urban water suppliers are required to describe management tools and options used that will maximize resources and minimize the need to import water from other regions.

BAWSCA agencies have long -term contracts with SFPUC to purchase water. The 26 BAWSCA agencies rely on SFPUC imported water as a significant source of high -quality potable water that is not pumped from groundwater basins or directly diverted from the Sacramento Bay-Delta.54 Several of the BAWSCA agencies (not including the City of Milpitas) do not have alternate water supplies and solely rely on SFPUC to supply water for their service area. Over the past decade, the City has taken significant demand management measures to reduce its water demand. The City’s increasingly lower GPCD is evidence that the City’s demand management tools are successful. The City continues to implement advanced technology and other measures to reduce demand for its SFPUC supply.

Below is a summary of the City’s water management tools that are being implemented and planned to minimize the need for imported SFPUC water.

The City will work closely and continuously with its customers when implementing the Level 6 WSCP measures.

Since extended emergency reductions of more than 50% are unprecedented and will be very difficult to sustain, additional alternate supplies and measures may be necessary.

54 SFPUC, 2025 Draft UWMP.

City of Milpitas 2025 Urban Water Management Plan DRAFT 85 In recent years, the City has invested in modern technologies and implemented the following measures:
• As of 2025, 100% of Advanced Metering Infrastructure (AMI) meters were installed in the City’s service area for near real-time metering of water use. The City has invested $14M in this advanced technology to:
o Continuously track all meters and water use.
o Engage with customers about their water use and identify potential leaks through an email and text alert ‘ping’ within days , rather than through a bi -monthly bill with potentially abnormally high consumption and cost to customers.
o Provide almost real- time water consumption data for its customers through the City ’s AMI customer portal.
• Investment in modern technologies – Supervisory Control and Data Acquisition (SCADA) for:
o Pressure zone management.
o Spatial identification of maintenance areas for improved visibility of service areas requiring a higher level of maintenance.
o Spatial identification of line breaks and break frequency to prioritize line replacement. o Spatial identification of abnormally high water use to prioritize leak investigations and/or identify areas for water conservation measures.
• Evaluate, assess, and implement Ordinances that target water efficiency:
o Prohibition on water waste.
• Geographic Information Systems (GIS) is being used for system mapping. • Increased implementation of demand management measures. • Coordinate the use of additional recycled water.
• Coordinate with other water agencies to share regional water resources.

The City may pursue a managed groundwater well extraction program similar to neighboring water agencies, Alameda County Water District to the north and City of Santa Clara and San Jose Water to the south. The south- western portion of the City overlays a groundwater aquifer which is adequately productive therefore, in -pipe blending with SFPUC and Valley Water is a viable option for augmenting supply shortages. Four wells at an average withdrawal rate of 1.2 million MGD (450 million gallons per year) can prod uce up to 5 MGD of new water supply or the City. The extraction rate and volume is based on preliminary production tests of McCandless Well and Curtis Well which have indicated the aquifer in this zone produces 500-1,200 gallons per minute or an average of 850 gallons per minute. Prior to use, a State Water Quality Report must be completed, as well as treatment (if necessary) and disinfection. Assuming new wells would be of similar quality to that of Pinewood Well (the primary municipal well for Milpitas’ e mergency water supply), treatment for contaminants would be minimal. Issues to be resolved include both mineral and odor concerns which will require treatment or in -pipe blending with current water supplies. Planning for future wells, while an increase to the infrastructure costs, allows for better long-term supply reliability by expanding the City’s water supply portfolio which will allow the City to supplement water supply cutbacks in some or all drought scenarios. Wells also provide the City storage credits to offset above grade water storage requirements which also include infrastructure and land acquisition costs.

City of Milpitas 2025 Urban Water Management Plan DRAFT 86 Sustainability of wells and groundwater aquifers are based on aquifer recharge, as currently performed by Valley Water. The City, in concert with Valley Water, should study the feasibility of offsetting SFPUC supply reductions, as outlined in the Bay -Delta Plan and this UWMP, to determine the approximate quantity of groundwater and the rate at which groundwater can be extracted from the aquifer during various drought scenarios. If it is determined the aquifer has the capacity to offset most if not all of th e supply cutbacks from SFPUC, the City should develop a Water Supply Augmentation Feasibility Report to determine the recommended number and location of wells.

BAWSCA Water Conservation Programs
BAWSCA manages a Regional Water Conservation Program comprised of several programs and initiatives that support and augment Member Agencies’ and customers’ efforts to use water more efficiently. The implementation of the Regional Water Conservation Program builds upon the Demand Study ( completed in December of 2025). These efforts include both Core Programs (implemented regionally throughout the BAWSCA service area) and Subscription Programs (funded by individual Member Agencies that elect to participate an d implement them within their respective service areas).

BAWSCA’s Core Conservation Programs include organizing classes focused on sustainable and water- efficient landscape design, assistance related to automated metering infrastructure, and other associated programs that work to promote smart water use and prac tices. BAWSCA’s Subscription Programs include numerous rebate programs, educational programs that can be offered to area schools, technical assistance to Member Agencies in evaluating water loss, and programs that use data analytics to provide customized w ater-saving recommendations to customers. In total, BAWSCA offers 24 programs to its Member Agencies and that number continues to grow over time.

Each fiscal year, BAWSCA prepares an Annual Water Conservation Report that documents several conservation program metrics exemplifying the benefits of the Regional Water Conservation Program to all 26 of BAWSCA Member Agencies. Additionally, the report highlights how all 26 Member Agencies participate in one or more of the Subscription Programs offered by BAWSCA, such as rebates, water loss management and large landscape audits. The Demand Study indicates that through a combination of active and passive con servation, 16.14 mgd will be conserved by BAWSCA’s Member Agencies by 2050.

7.3 Drought Risk Assessment (DRA)
The DRA requires that every urban water supplier includes a drought risk assessment for its water service and develops Demand Management Measures (DMMs) and water supply projects and programs [Water Code Section 10635(b)].

The Water Code Section 10635(b) permits urban water suppliers to conduct an interim update or updates to this drought risk assessment within the five- year cycle of its urban water management plan update. This allows Valley Water Demand Management Reduced Delta Reliance Requirement

Valley Water, with the financial support of all its retailers as reflected in its water rates, has made significant investments in demand management and developing local supplies to reduce Santa Clara County’s reliance on the Delta watershed and increase regional self-reliance. These investments include:
• Conservation and demand management
• Recycled and purified water
• Dam improvements/seismic retrofits to lift storage restrictions on local reservoirs • Regional collaborations to increase self-reliance

City of Milpitas 2025 Urban Water Management Plan DRAFT 87 Suppliers to modify the DRA as more information becomes available, supplies or uses change, and in the event of unforeseen circumstances.

Suppliers must prepare a DRA that includes a description of the following:
• Data and methods used
• Basis for the supply shortage conditions
• Determination of the reliability of each source
• Comparison of total water supplies and uses during the drought In accordance with Water Code Section 10612, the DRA evaluation is based on the five driest consecutive years on record. However, Water Code Section 10635 also requires that the analysis includes plausible changes in climate, regulations, and other locally applicable criteria.

For the DRA, SFPUC derived the five -year consecutive drought based on the driest five -year sequence in the hydrologic record and provided two scenarios for BAWSCA agencies to choose from. The supply conditions provided by SFPUC satisfy the Water Code requirements. SFPUC has provided information about the likelihood of this severe condition in their UWMP. The historic five driest consecutive years on record provided by SFPUC are required to be presented as if they occur over the next five years, 202 6 through 2030 in the DRA. They are analyzed in this Section.

Table 7-5will demonstrate water supply reliability during the long-term drought. In Table 7-5, the Drought Risk Assessment (DRA), DWR requests suppliers to provide their five-year drought Risk Assessment (five-year drought sequence, supply and demand for comparison), from 202 6 through 2030, including planned Water Shortage Contingency Plan (WSCP) Actions, to address Water Code Section 10635(b).

In Table 7 -5, the DRA includes the City’s supply reliability using SFPUC scenario with Bay -Delta Plan. SFPUC projects that in multiple dry years, with the Bay-Delta Plan, the wholesale volume available will range from 71% of normal in the first year and second year, and 72% of normal in the third year to fifth (Data Sources: SFPUC 2025 UWMP Water Supply Reliability Letter, Table 8).
55 SFPUC’s projections for available supplies for wholesale agencies translate to significant cutback allocations for all BAWSCA agencies (2025 UWMP Wholesale Customer Dry Year Allocations, 3/25/2026).

The City will experience water supply shortfalls with the implementation of the Bay-Delta Plan, for multiple (five) dry years. These shortfalls will invoke the City’s WSCP in the first year (2026) through fifth year (2030) of a multi- year drought. To reduce the need for continued extreme use reductions, the City will need to implement demand reduction actions as described in the Water Shortage Contingency Plan and consider groundwater supplies as necessary.

Water Shortage Contingency Plan (WSCP) Actions, to address Water Code Section 10635(b) To achieve reductions of SFPUC supply during shortages, the City will invoke all elements of the WSCP. The City’s measures could include, but not be limited to the following:
• Extremely restricted water supplies
• Strict enforcement of water waste prohibitions
• Restrictions on outdoor domestic water use, except for fire-fighting and critical needs • Prioritizing water use for essential domestic sanitation and other critical needs • No irrigation with domestic water permitted

55 SFPUC: March 11, 2026, 2025 Water Supply Reliability Letter, Table 8.

City of Milpitas 2025 Urban Water Management Plan DRAFT 88 • Mandatory reductions on indoor water uses
During the 2021-2023 drought, the City sustained water use reductions by invoking multiple water reduction measures, including continued public notifications and conservation messaging, rebates for water- efficient fixtures and turf removal, and enforcing indoor and outdoor water use restrictions. Although staff could not identify exact savings associated with implementing specific measures , it was clear that outdoor water use restrictions contributed significantly to water use reductions. Additionally, the City’s AMI meter technology can further increase water use reductions by allowing more frequent monitoring of consumption data and pressure zone management.

The key means by which the City will be able to sustain more than 40% reductions, for extended periods of time, without additional supplies, will require severe restrictions of potable use outdoors and lowering its water losses. For prolonged reductions of 40-50%, the City could achieve approximately 41% reductions. Using its 2025 domestic water production and wastewater discharge data:
• The City’s production: 3,238 MG/year
• Wastewater to SVCW: 2,308 MG/year
• Non-sewered use including Irrigation water = Production ( 3,238) – [wastewater (2,308) + water loss (302)] = 1,232 MG/year
Therefore, non-sewered use in 2025 was approximately 1,232 MG/year in 2025 or almost 40% of the City’s 2020 water demand. Although savings of 41 % from non-sewered are unlikely, the potential for the highest potable water savings are from outdoor and other non-potable uses.

These cutbacks follow the WSA and are contractually within SFPUC's planned Level of Service, limiting supply cutbacks to less than 20% for its wholesale customers. During a five-year drought, shortages of water supply result for the City’s service area.

DWR requires that suppliers only use one scenario to input data into the Water Use Efficiency Data (WUE) portal.

7.3.1 DRA Data, Methods, and Basis for Water Shortage Condition DWR requires that suppliers provide a description of the data used for the DRA. Although SFPUC and BAWSCA data are described earlier in this chapter, and because the DRA can be updated separately from the UWMP five- year plan cycle, DWR requires a description of the data in the DRA.

In its DRA, the City includes information and the tables about SFPUC and BAWSCA source(s) of data. SFPUC has developed hydrologic models based on the DWR-required scenarios for a multi-year drought. All documentation received from SFPUC and BAWSCA for decisions to determine supply shortage conditions, used for the City ’s DRA is provided in Appendix E. Details about SFPUC’s RWS models are included in SFPUC’s Draft 2025 UWMP. 56 All the Scenario 1 tables presented earlier in this chapter assume full implementation by SFPUC of the Bay-Delta Plan Amendment. All BAWSCA tables assume that the wholesale customers may purchase up to 184 MGD from the RWS through 2045. When 184 MGD or100% of SFPUC’s water supply is available to the wholesale customers, 100% of the City’s ISG, or 9.232 MGD per year, is available to the City. Assumptions about the status of the dry- year water supply projects included in SFPUC’s Water System Improvement Program (WSIP) are provided in the table ‘WSIP Project Assumptions for RWS Supply Modeling’.57 The tables reflect instream flow requirements at San Mateo and Alameda Creeks.

56 SFPUC. (2025). Draft 2025 UWMP, https://www.sfpuc.gov/sites/default/files/documents/2025-UWMP-Public-Draft.pdf. 57 SFPUC Regional Water System supply reliability letter from SFPUC, Table 2 , March 11, 2026 (see Appendix F).

City of Milpitas 2025 Urban Water Management Plan DRAFT 89

7.3.2 DRA Individual Water Source Reliability
DWR requires suppliers to include an assessment of the reliability of each water source over the five - consecutive-year drought under a variety of water shortage conditions in the DRA. In contrast, the water service reliability assessment only requires an assessment of total water supply.

In its DRA, the City presents the potential challenges to its normal year supplies. Unlike the previous drought cutbacks, if the Bay -Delta Plan is implemented, as SFPUC presents it in its extreme supply reductions, using Scenario 1, during multi -year droughts, severe cutbacks from the normal w holesale supply are projected to result. SFPUC projects reductions in their wholesale supply of up to 48%. The RWS-wide supply reductions also translate to the most severe cutbacks during multi-year droughts for the City of up to 48%.

The cutback values presented in this chapter are uncertain and could change, therefore users and readers of the City’s 2025 UWMP are cautioned to contact the City to obtain updated information prior to making decisions based on water supply and demand values in this plan.

The regulatory conditions and negotiations about the Bay -Delta Plan are continually evolving, therefore conditions could change from those documented in SFPUC’s and the City’s 2025 UWMPs. SFPUC’s two scenarios present contrasting results. Based on the current negotiations between SFPUC and the State Water Board, as well as other stakeholders, neither of the two scenarios appears to be final.

With this uncertainty, the City may consider an update to its DRA (see Section 7.3) prior to th e 2030 UWMP update if significant new information becomes available. The Water Code Section 10635(b) permits urban water suppliers to conduct an interim update or updates to their DRA within the five-year cycle of its UWMP update.

The City will have to work closely with BAWSCA and continuously with its customers when implementing Levels 5 and 6 WSCP measures. Since extended emergency reductions of more than 50% are unprecedented and will be very difficult to sustain , even implementation of the strongest mitigation measures in Level 6 of the City ’s 2025 WSCP, will likely require augmentation with alternate water supplies.

Separate Potable and Non-Potable. The City does not have a non-potable source of water; therefore, its DRA is for its SFPUC and Valley Water potable water supply.

Monthly or Other Time -Step. DWR recommends that suppliers conduct their DRA on a time -step that best illuminates water supply and use constraints that may affect water shortage conditions . For its DRA, the City uses an annual time -step, becau se the City ’s SFPUC supply is based on an annual allocation, rather than a monthly allocation. Due to the Mediterranean climate in the City’s service area, variability in seasonal temperatures and rainfall are normal, therefore monthly variability in water use is typical for the service area.

7.3.3 DRA Total Water Supply and Use Comparison
The City submitted Table 7-5, with Bay-Delta Plan in the WUE portal to be in compliance with the 2025 UWMP requirements and to be consistent with its supplier, SFPUC. The City’s DRA may be revised outside of its 2025 UWMP.

City of Milpitas 2025 Urban Water Management Plan DRAFT 90 Table 7-5. Five-year Drought Risk Assessment – With Bay-Delta Plan Submittal Table 7-5 Retail: Five-Year Drought Risk Assessment - Water Code Section 10635(b)(3) 2026 Total
Total Water Use (MG) 3,180
Total Supplies (MG) 3,025
Surplus/Shortfall w/o WSCP Action (155)
OPTIONAL Planned WSCP Actions (use reduction and supply augmentation) WSCP - use reduction savings benefit (MG) 155
Revised Surplus/(shortfall) 0
2027 Total
Total Water Use (MG) 3,190
Total Supplies (MG) 3,026
Surplus/Shortfall w/o WSCP Action (164)
OPTIONAL Planned WSCP Actions (use reduction and supply augmentation) WSCP - use reduction savings benefit (MG) 164
Revised Surplus/(shortfall) 0
2028 Total
Total Water Use (MG) 3,230
Total Supplies (MG) 3,032
Surplus/Shortfall w/o WSCP Action (198)
OPTIONAL Planned WSCP Actions (use reduction and supply augmentation) WSCP - use reduction savings benefit (MG) 198
Revised Surplus/(shortfall) 0
2029 Total
Total Water Use (MG) 3,250
Total Supplies (MG) 2,985
Surplus/Shortfall w/o WSCP Action (265)
OPTIONAL Planned WSCP Actions (use reduction and supply augmentation) WSCP - use reduction savings benefit (MG) 265
Revised Surplus/(shortfall) 0
2030 Total
Total Water Use (MG) 3,270
Total Supplies (MG) 2,991
Surplus/Shortfall w/o WSCP Action (279)
OPTIONAL Planned WSCP Actions (use reduction and supply augmentation) WSCP - use reduction savings benefit (MG) 279
Revised Surplus/(shortfall) 0

City of Milpitas 2025 Urban Water Management Plan DRAFT 91 Submittal Table 7-5 Retail: Five-Year Drought Risk Assessment - Water Code Section 10635(b)(3) NOTES for Table 7-6 (DWR Submittal Table 7-5):

1. Supply and use include both potable water and recycled water.

2. Multiple dry year use expected to align with BAWSCA Demand Study projected normal year water use, for potable and non-potable. BAWSCA Demand Study projections include climate change as well as passive and active conservation.

3. Non-potable supply totals based on projected recycled supplies meeting recycled water demands.

4. Potable supply totals include Valley Water and SFPUC delivered supplies.

5. SFPUC potable water supplies based on projected supply by year and year type per "2025 UWMP Wholesale Customer Dry Year Allocations_FINAL.xlsx", WITH implementation of the 2018 amendments to the Bay-Delta Water Quality Control Plan (Bay-Delta Plan Amendment).

6. Valley Water multiple dry year supplies align with Valley Water normal year supplies with an additional reduction of 5% in Valley Water potable water supplies expected in a multiple dry years 4 and 5. Valley Water supplies based on their Water Supply Master Plan 2050 low-cost portfolio:

Semitropic storage (350 TAF) through 2035; groundwater banking (250 TAF) starting 2040; Sisk Reservoir expansion in 2035; DCP in 2045; Pure Water Silicon Valley in 2035. Valley Water model multi-year drought is 1988–1992; this remains the most severe extended drought in the record.

Reasonably available supply is water in storage above thresholds for emergency needs, subsidence protection, and operational withdrawal limits for each storage facility.

7. Shortfall to be preliminarily addressed with WSCP use reduction actions as reported in Table 8-3.

Stage 1 drought response actions would yield the anticipated 5%-10% use reduction estimated.

8. WSCP supply augmentation benefits as reported in Table 8-2 and including groundwater production will be implemented if necessary.

City of Milpitas 2025 Urban Water Management Plan DRAFT 92 8 WATER SHORTAGE CONTINGENCY PLAN NING
Lay Description
The California Water Code Section 10632 requires every urban water supplier that serves more than 3,000 acre- feet per year or has more than 3,000 connections to prepare and adopt a standalone WSCP as part of its UWMP.

The WSCP is required to allow Suppliers to plan for a greater than 50% supply shortage and is due to be updated every five years. Water shortage contingency planning is a strategic planning process in which the City of Milpitas engages to prepare for and respond to water shortages, which occur when available water supply is insufficient to meet the normal expected customer water use. A shortage may occur due to several reasons, such as water supply quality changes, climate change, drought, and catastrophic events (e.g., earthquake). The City’s WSCP provides real-time water supply availability assessment and structured steps designed to respond to actual conditions. This level of detailed planning and preparation will help maintain reliable supplies and reduce the impacts of supply interruptions. This WSCP is due to be updated, based on new requirements, every five years and will be adopted as a current update for submission to DWR by July 1, 2026.

8.1 Overview of the WSCP
The WSCP serves as the operating manual that the City will use to prevent catastrophic service disruptions through proactive, mitigation of water shortages . The WSCP contains documented processes and procedures, which are given legal authority through the Water Shortage Contingency Response Ordinance (Water Code Section 10632). This way, when shortage conditions arise, the City’s governing body, its staff, and the public can easily identify and efficiently implement pre -determined steps to m itigate a water shortage to the level appropriate for the degree of anticipated shortfall. Figure 8.1 illustrates the interdependent relationship between the three procedural documents related to planning for and responding to water shortages.

Figure 8-1. Water Shortage Contingency Plan Flow of Information

The City’s WSCP is provided in Appendix D. It includes the steps to assess if a water shortage is occurring and the level of shortage actions to achieve the best response as appropriate to the conditions.

The WSCP contains the following prescriptive elements:
• An analysis of water supply reliability

City of Milpitas 2025 Urban Water Management Plan DRAFT 93 • The drought shortage actions for each of the six standard water shortage levels that correspond to water shortage percentages ranging from 10% to greater than 50% • An estimate of the potential to close the supply gap for each measure • Protocols and procedures to communicate identified actions for any current or predicted water shortage conditions
• Procedures for an Annual Water Supply and Demand Assessment • Monitoring and reporting requirements to determine customer compliance • Procedures for reevaluating and improving the WSCP

8.2 Summary of Water Shortage Response Strategy and Required DWR Tables This WSCP is organized into three main chapters as listed below, with Chapter 3 aligned with the California Water Code Section 16032 requirements. In addition to the WSCP, Chapter 6 of this UWMP has further details of the City’s water supply systems.

Chapter 1 – Introduction and WSCP Overview. This chapter gives an overview of the WSCP fundamentals.

Chapter 2 – Background Information. This chapter provides information on the City’s water service area.

Chapter 3 – Water Shortage Contingency Response and Preparedness Planning. This chapter describes the procedures, policies, and response actions used to monitor water supply conditions and implement staged responses to water shortages.

Section 3.1 – Water Supply Reliability Analysis. This section provides a summary of the water supply analysis and water reliability findings from the 2025 UWMP.

Section 3.2 – Annual Water Supply and Demand Assessment Procedures. This section provides a description of procedures to conduct and approve the Annual Assessment.

Section 3.3 – Six Standard Water Shortage Levels. This section explains the WSCP’s six standard water shortage levels corresponding to progressive ranges of up to 10, 20, 30, 40, 50, and more than 50% shortages.

Section 3.4 – Shortage Response Actions. This section describes the WSCP’s shortage response actions that align with the defined shortage levels.

Section 3. 5 – Seismic Risk Assessment and Mitigation Plan. This section addresses the vulnerability of the systems to earthquakes and the Federal Emergency Management Agency -approved Santa Clara County Multijurisdictional Hazard Mitigation Plan.

Section 3.6 – Communication Protocols. This section addresses communication protocols and procedures to inform customers, the public, interested parties, and local, regional, and state governments, regarding any current or predicted shortages and any resulting shortage response actions.

Section 3.7 – Compliance and Enforcement. This section describes customer compliance, enforcement, appeal, and exemption procedures for triggered shortage response actions.

Section 3.8 – Legal Authorities. This section describes the legal authorities that enable the City to implement and enforce its shortage response actions.

Section 3. 9 – Financial Consequences of the WSCP . This section provides a description of the financial consequences of and responses to drought conditions.

Section 3.10 – Monitoring and Reporting. This section describes monitoring and reporting requirements and procedures that ensure appropriate data is collected, tracked, and analyzed for purposes of monitoring customer compliance and meeting state reporting requirements.

City of Milpitas 2025 Urban Water Management Plan DRAFT 94 Section 3.11– WSCP Refinement Procedures. This section addresses reevaluation and improvement procedures for monitoring and evaluating the functionality of the WSCP.

Section 3.12 – Special Water Feature Distinction. This section defines water features that are artificially supplied with water.

Section 3.13 – Plan Adoption, Submittal, and Implementation. This section provides a record of the process the City followed to adopt and implement its WSCP.

The WSCP is based on adequate details of demand reduction and supply augmentation measures structured to match varying degrees of shortage will inform the relevant stakeholders of what to expect during a water shortage. The City has adopted water shortage levels consistent with the requirements identified in Water Code Section 10632 (a)(3)(A) (Table 8-1 here and in the Water Shortage Contingency Plan).

Table 8-1. Water Shortage Contingency Plan Levels
Submittal Table 8-1: Cross-reference for Standard vs Supplier Shortage Levels Water Code Section 10632(a)(3)(B)

Check the box if the Supplier uses the Standard six levels of water shortage.

Proceed to the next table.

Standard
Shortage Levels
Percent Shortage
Range Shortage Response Actions
0 0% (Normal)
A Level 0 Water Supply Shortage condition exists when the City notifies its water users that no supply reductions are anticipated in this year. The City proceeds with planned water efficiency best practices to support consumer demand reduction in line with state mandated requirements and local City goals for water supply reliability. Permanent water waste prohibitions are in place as stipulated in the City’s Water Shortage Response Ordinance. 1 Up to 10%
A Level 1 Water Supply Shortage condition exists when the City notifies its water users that due to drought or other supply reductions, a consumer demand reduction of up to 10% is necessary to make more efficient use of water and respond to existing water conditions. The City shall implement the mandatory Level 1 conservation measures identified in this WSCP. The type of event that may prompt the City to declare a Level 1 Water Supply Shortage may include, among other factors, a finding that its wholesale water provider calls for extraordinary water conservation. 2 Up to 20%
A Level 2 Water Supply Shortage condition exists when the City notifies its water users that due to drought or other supply reductions, a consumer demand reduction of up to 20% is necessary to make more efficient use of water and respond to existing water conditions. Upon declaration of a Level 2 Water Supply Shortage condition, the City shall implement the mandatory Level 2 conservation measures identified in this WSCP.

City of Milpitas 2025 Urban Water Management Plan DRAFT 95 Submittal Table 8-1: Cross-reference for Standard vs Supplier Shortage Levels Water Code Section 10632(a)(3)(B)

Check the box if the Supplier uses the Standard six levels of water shortage.

Proceed to the next table.

Standard
Shortage Levels
Percent Shortage
Range Shortage Response Actions
3 Up to 30%
A Level 3 Water Supply Shortage condition exists when the City declares a water shortage emergency condition pursuant to California Water Code section 350 and notifies its residents and businesses that up to 30% consumer demand reduction is required to ensure sufficient supplies for human consumption, sanitation and fire protection. The City must declare a Water Supply Shortage Emergency in the manner and on the grounds provided in California Water Code section 350.
4 Up to 40%
A Level 4 Water Supply Shortage condition exists when the City declares a water shortage emergency condition pursuant to California Water Code section 350 and notifies its residents and businesses that up to 40% consumer demand reduction is required to ensure sufficient supplies for human consumption, sanitation and fire protection. The City must declare a Water Supply Shortage Emergency in the manner and on the grounds provided in California Water Code section 350.
5 Up to 50%
A Level 5 Water Supply Shortage condition exists when the City declares a water shortage emergency condition pursuant to California Water Code section 350 and notifies its residents and businesses that up to 50% or more consumer demand reduction is required to ensure sufficient supplies for human consumption, sanitation and fire protection. The City must declare a Water Supply Shortage Emergency in the manner and on the grounds provided in California Water Code section 350.
6 >50%
A Level 6 Water Supply Shortage condition exists when the City declares a water shortage emergency condition pursuant to California Water Code section 350 and notifies its residents and businesses that greater than 50% or more consumer demand reduction is required to ensure sufficient supplies for human consumption, sanitation and fire protection.

The City must declare a Water Supply Shortage Emergency in the manner and on the grounds provided in California Water Code section 350.

The supply augmentation actions that align with each shortage level are described in Table 8 -2 here and in the WSCP. These augmentations represent short-term management objectives triggered by the WSCP and do not overlap with the long-term new water supply development or supply reliability enhancement projects.

City of Milpitas 2025 Urban Water Management Plan DRAFT 96 Table 8-2. Supply Augmentation and Other Actions
Submittal Table 8-2 Retail: Supply Augmentation and Other Actions - Water Code Section 10632(a)(4)(A), (C), and (E)
Yes Is the Supplier completing this table using the standard six levels? (yes/no) Shortage
Level
Supply Augmentation
Methods and Other
Actions by Water
Supplier
How much is this going to
reduce the shortage gap?
Additional Explanation or Reference
Volume or
Percentage
Shortage Gap
Reduction
(MG)
1 Other Actions (describe) Percentage 0-10%
Utilize 1-5 additional City-owned
groundwater wells as needed. Each
has a capacity of 1.2 MGD per West
Yost April 2021 Shortage Evaluation.
2 Other Actions (describe) Percentage 10-20%
Utilize 1-5 additional City-owned
groundwater wells as needed. Each
has a capacity of 1.2 MGD per West
Yost April 2021 Shortage Evaluation.
3 Other Actions (describe) Percentage 20-30%
Utilize 1-5 additional City-owned
groundwater wells as needed. Each
has a capacity of 1.2 MGD per West
Yost April 2021 Shortage Evaluation.
4 Other Actions (describe) Volume 1752
Utilize 1-5 additional City-owned
groundwater wells as needed. Each
has a capacity of 1.2 MGD per West
Yost April 2021 Shortage Evaluation.
5 Other Actions (describe) Volume 1752
Utilize 1-5 additional City-owned
groundwater wells as needed. Each
has a capacity of 1.2 MGD per West
Yost April 2021 Shortage Evaluation.
6 Other Actions (describe) Volume 1752
Utilize 1-5 additional City-owned
groundwater wells as needed. Each
has a capacity of 1.2 MGD per West
Yost April 2021 Shortage Evaluation.

NOTES:

1. The City currently has three groundwater wells that are used for emergency use only and permitted to be operated no more than 5 consecutive days, and for no more than 15 calendar days per year. They pump at

1.2 MGD and are not designed as production supply wells. By year 2030, these groundwater wells will become an active non-emergency supply source and be able to operate at full production rate in dry year conditions.

2. By 2035, one or more additional wells pumping at 1.2 MGD or 438 MGY will be online yielding a total well capacity of 1,752 MGY for all groundwater wells. More than one well may be built between 2030 and 2035 depending on anticipated shortfall and well pumping capacities.

The demand reduction measures that align with each shortage level are described in Table 8 -3 here and in the WSCP. This table also estimates the extent to which each action will reduce the gap between supply and demand, demonstrating that the selected suite of shortage response actions can be expected to meet the requirements of a given shortage level.

City of Milpitas 2025 Urban Water Management Plan DRAFT 97 Table 8-3. Demand Reduction Actions
Submittal Table 8-3 Retail: Demand Reduction Actions - Water Code Section 10632(a)(4)(B) and (E) Yes Is the Supplier completing this table using the standard six levels? (yes/no) Shortage
Level
Demand
Reduction
Actions
How much is this going to reduce
the shortage gap? Additional Explanation or
Reference
Penalty,
Charge, or
Other
Enforcement?
Volume or
Percentage
Shortage Gap
Reduction Value
(MG)
0 Other water
feature or
swimming
pool
restriction
Percentage
Statewide
Prohibition is
Required
Cleaning, filling, or
operating water features,
such as decorative
fountains, except where
the water is part of a
recirculating system.

No
0 Other Percentage
Statewide
Prohibition is
Required
Washing or hosing down
vehicles is prohibited
except by use of a
handheld container, hose
with an automatic shut off
device, or at a commercial
car wash.

No
0 Other -
Prohibit use
of potable
water for
washing
hard
surfaces
Percentage
Statewide
Prohibition is
Required
Washing hard or paved
surfaces is prohibited
except to alleviate safety or
sanitary hazards using a
handheld container, hose
with an automatic shut off
device, or a low-volume
high pressure cleaning
machine that recycles used
water.

No
0 Landscape -
Restrict or
prohibit
runoff from
landscape
irrigation
Percentage
Statewide
Prohibition is
Required
Watering vegetated areas
in a manner that causes
excessive water flow or
runoff onto an adjoining
sidewalk, driveway, street,
alley, gutter, or ditch is
prohibited.

No
0 Landscape -
Other
landscape
restriction or
prohibition
Percentage
Statewide
Prohibition is
Required
Irrigating ornamental turf
on public street medians is
prohibited.

No
0 Landscape -
Other
landscape
restriction or
prohibition
Percentage
Statewide
Prohibition is
Required
No landscape watering
shall occur within 48 hours
after measurable
precipitation.

No

City of Milpitas 2025 Urban Water Management Plan DRAFT 98 Submittal Table 8-3 Retail: Demand Reduction Actions - Water Code Section 10632(a)(4)(B) and (E) Yes Is the Supplier completing this table using the standard six levels? (yes/no) Shortage
Level
Demand
Reduction
Actions
How much is this going to reduce
the shortage gap? Additional Explanation or
Reference
Penalty,
Charge, or
Other
Enforcement?
Volume or
Percentage
Shortage Gap
Reduction Value
(MG)
0 Landscape -
Other
landscape
restriction or
prohibition
Percentage
Ongoing long-term
conservation
savings measure.

N/A to WSCP
quantifiable
savings.

Prohibited use of broken or
defective plumbing,
sprinkler, watering or
irrigation systems
No
0 Landscape -
Other
landscape
restriction or
prohibition
Percentage
Ongoing long-term
conservation
savings measure.

N/A to WSCP
quantifiable
savings.

Prohibited use of potable
water for outdoor irrigation
in newly constructed
homes and buildings,
except with drip or
microspray irrigation
systems.

No
0 CII -
Restaurants
may only
serve water
upon
request
Percentage
Ongoing long-term
conservation
savings measure.

N/A to WSCP
quantifiable
savings.

CII - Restaurants may only
serve water upon request No
0 CII - Other
CII
restriction or
prohibition
Percentage
Ongoing long-term
conservation
savings measure.

N/A to WSCP
quantifiable
savings.

No water in new, added or
altered cooling system
equipment unless at least
fifty percent (50%) of the
water is recycled.

No
0 Other -
Prohibit
vehicle
washing
except at
facilities
using
recycled or
recirculating
water
Percentage
Ongoing long-term
conservation
savings measure.

N/A to WSCP
quantifiable
savings.

All new commercial car
wash and laundry facilities
must re-circulate the wash
water.

No

City of Milpitas 2025 Urban Water Management Plan DRAFT 99 Submittal Table 8-3 Retail: Demand Reduction Actions - Water Code Section 10632(a)(4)(B) and (E) Yes Is the Supplier completing this table using the standard six levels? (yes/no) Shortage
Level
Demand
Reduction
Actions
How much is this going to reduce
the shortage gap? Additional Explanation or
Reference
Penalty,
Charge, or
Other
Enforcement?
Volume or
Percentage
Shortage Gap
Reduction Value
(MG)
0 Landscape -
Limit
landscape
irrigation to
specific
times
Percentage
Ongoing long-term
conservation
savings measure.

N/A to WSCP
quantifiable
savings.

Watering or irrigation of
vegetated areas is
prohibited between 9 am
and 6 pm except by use of
a hand held device, hose
equipped with an
automatic shutoff device,
or for adjusting or repairing
an irrigation system for
short periods of time.

No
0 Other -
Require
automatic
shut of
hoses
Percentage
Ongoing long-term
conservation
savings measure.

N/A to WSCP
quantifiable
savings.

Use a shutoff nozzle on
hoses. No
0 Pools and
Spas -
Require
covers for
pools and
spas
Percentage
Ongoing long-term
conservation
savings measure.

N/A to WSCP
quantifiable
savings.

Pools and spas shall be
covered when not in use to
prevent evaporation.

No
0 Other -
Prohibit use
of potable
water for
construction
and dust
control
Percentage
Ongoing long-term
conservation
savings measure.

N/A to WSCP
quantifiable
savings.

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).

No
0 Landscape -
Limit
landscape
irrigation to
specific days
Percentage
Ongoing long-term
conservation
savings measure.

N/A to WSCP
quantifiable
savings.

Irrigation shall be limited to
4 days per week turf
watering when using
potable water.

No

City of Milpitas 2025 Urban Water Management Plan DRAFT 100 Submittal Table 8-3 Retail: Demand Reduction Actions - Water Code Section 10632(a)(4)(B) and (E) Yes Is the Supplier completing this table using the standard six levels? (yes/no) Shortage
Level
Demand
Reduction
Actions
How much is this going to reduce
the shortage gap? Additional Explanation or
Reference
Penalty,
Charge, or
Other
Enforcement?
Volume or
Percentage
Shortage Gap
Reduction Value
(MG)
0 Landscape -
Other
landscape
restriction or
prohibition
Percentage
Ongoing long-term
conservation
savings measure.

N/A to WSCP
quantifiable
savings.

Prohibited use of potable
water for outdoor irrigation
in newly constructed
homes and buildings,
except with drip or
microspray irrigation
systems.

No
0 Landscape -
Other
landscape
restriction or
prohibition
Percentage
Ongoing long-term
conservation
savings measure.

N/A to WSCP
quantifiable
savings.

Prohibited use of potable
water for the irrigation of
nonfunctional turf located
on commercial, industrial,
and institutional
properties, other than
cemeteries, and on
properties of homeowners'
associations, common
interest developments, and
community service
organizations or similar
entities.

No
1 Landscape -
Limit
landscape
irrigation to
specific
times
Percentage 0-5%
Watering or irrigation of
vegetated areas is
prohibited between 9 am
and 6 pm except by use of
a hand held device, hose
equipped with an
automatic shutoff device,
or for adjusting or repairing
an irrigation system for
short periods of time.

Yes
1 Landscape -
Limit
landscape
irrigation to
specific days
Percentage 0-5%
Irrigation shall be limited to
4 days per week turf
watering when using
potable water.

Yes
1 Expand
Public
Information
Campaign
Percentage 0-1%
Community Outreach and
Messaging (Expand Public
Information Campaign)
Yes

City of Milpitas 2025 Urban Water Management Plan DRAFT 101 Submittal Table 8-3 Retail: Demand Reduction Actions - Water Code Section 10632(a)(4)(B) and (E) Yes Is the Supplier completing this table using the standard six levels? (yes/no) Shortage
Level
Demand
Reduction
Actions
How much is this going to reduce
the shortage gap? Additional Explanation or
Reference
Penalty,
Charge, or
Other
Enforcement?
Volume or
Percentage
Shortage Gap
Reduction Value
(MG)
1 Reduce
System
Water Loss
Percentage 0-5%
Real Loss Reduction -
Pressure Management and
More Aggressive Leak
Detection and Repair
Yes
1 Increase
Water
Waste
Patrols
Percentage 0-1% Increase Water Waste
Patrols Yes
1 Expand
Public
Information
Campaign
Percentage 0-1%
Expand promotion and
outreach about rebates
available
No
2 Improve
Customer
Billing
Percentage 0-1%
Improve AMI Leak Reports
to include more details on
water use
No
2 Other -
Customers
must repair
leaks,
breaks, and
malfunctions
in a timely
manner
Percentage 0-1% Fix leaks or faulty sprinklers
promptly/within 5 days. Yes
2 Landscape -
Other
landscape
restriction or
prohibition
Percentage 0-1%
Prohibited use of broken or
defective plumbing,
sprinkler, watering or
irrigation systems.

Yes
2 Landscape -
Limit
landscape
irrigation to
specific days
Percentage 5-10%
Irrigation shall be limited to
3 days per week turf
watering when using
potable water. Plant
containers, trees, shrubs
and vegetable gardens may
be watered additional days
using only drip irrigation or
hand watering.

Yes

City of Milpitas 2025 Urban Water Management Plan DRAFT 102 Submittal Table 8-3 Retail: Demand Reduction Actions - Water Code Section 10632(a)(4)(B) and (E) Yes Is the Supplier completing this table using the standard six levels? (yes/no) Shortage
Level
Demand
Reduction
Actions
How much is this going to reduce
the shortage gap? Additional Explanation or
Reference
Penalty,
Charge, or
Other
Enforcement?
Volume or
Percentage
Shortage Gap
Reduction Value
(MG)
2 Water
Features -
Restrict
water use
for
decorative
water
features,
such as
fountains
Percentage 0-1%
Filling or refilling
ornamental lakes and
ponds is prohibited.

Ornamental lakes and
ponds that sustain aquatic
life of significant value and
were actively managed
prior to the storage
declaration are exempt.

Yes
2 Pools and
Spas -
Require
covers for
pools and
spas
Percentage 0-1% Pools and Spas - Require
covers for pools and spas Yes
2 Decrease
Line Flushing Percentage 0-1% Decrease Line Flushing Yes 2 CII -
Restaurants
may only
serve water
upon
request
Percentage 0-1% CII - Restaurants may only
serve water upon request Yes
2 Pools - Allow
filling of
swimming
pools only
when an
appropriate
cover is in
place
Percentage 0-1%
Pools - Allow filling of
swimming pools only when
an appropriate cover is in
place.

Yes
3 Other -
Customers
must repair
leaks,
breaks, and
malfunctions
in a timely
manner
Percentage 0-1% Fix leaks or faulty sprinklers
within 4 days. Yes

City of Milpitas 2025 Urban Water Management Plan DRAFT 103 Submittal Table 8-3 Retail: Demand Reduction Actions - Water Code Section 10632(a)(4)(B) and (E) Yes Is the Supplier completing this table using the standard six levels? (yes/no) Shortage
Level
Demand
Reduction
Actions
How much is this going to reduce
the shortage gap? Additional Explanation or
Reference
Penalty,
Charge, or
Other
Enforcement?
Volume or
Percentage
Shortage Gap
Reduction Value
(MG)
3 Other -
Prohibit
vehicle
washing
except at
facilities
using
recycled or
recirculating
water
Percentage 0-1%
Car washing is only
permitted using a
commercial carwash that
recirculates water or by
high pressure/low volume
wash systems.

Yes
3 Other -
Prohibit use
of potable
water for
construction
and dust
control
Percentage 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).

Yes
3 Landscape -
Limit
landscape
irrigation to
specific days
Percentage 10-25%
Irrigation shall be limited to
2 days per week turf
watering when using
potable water. Plant
containers, trees, shrubs
and vegetable gardens may
be watered additional days
using only drip irrigation or
hand watering.

Yes
3 Other water
feature or
swimming
pool
restriction
Percentage 0-1%
Decorative water features
that use potable water
must be drained and kept
dry.

Yes
3 CII - Other
CII
restriction or
prohibition
Percentage 0-1%
No water in new, added or
altered cooling system
equipment unless at least
fifty percent (50%) of the
water is recycled.

Yes

City of Milpitas 2025 Urban Water Management Plan DRAFT 104 Submittal Table 8-3 Retail: Demand Reduction Actions - Water Code Section 10632(a)(4)(B) and (E) Yes Is the Supplier completing this table using the standard six levels? (yes/no) Shortage
Level
Demand
Reduction
Actions
How much is this going to reduce
the shortage gap? Additional Explanation or
Reference
Penalty,
Charge, or
Other
Enforcement?
Volume or
Percentage
Shortage Gap
Reduction Value
(MG)
4 Other -
Customers
must repair
leaks,
breaks, and
malfunctions
in a timely
manner
Percentage 0-1% Fix leaks or faulty sprinklers
within 3 days. Yes
4 Landscape -
Limit
landscape
irrigation to
specific days
Percentage 5-20%
Irrigation shall be limited to
1 days per week turf
watering when using
potable water. Plant
containers, trees, shrubs
and vegetable gardens may
be watered additional days
using only drip irrigation or
hand watering.

Yes
4 Other water
feature or
swimming
pool
restriction
Percentage 0-1%
Existing pools shall not be
emptied and refilled using
potable water unless
required for public health
and safety purposes.

Yes
4 Other water
feature or
swimming
pool
restriction
Percentage 0-1% No new permits for pools
will be issued. Yes
4 Landscape -
Prohibit
certain types
of landscape
irrigation
Percentage 0-1%
Irrigation of golf courses
only allowed for greens and
tees area.

Yes
5 Other -
Customers
must repair
leaks,
breaks, and
malfunctions
in a timely
manner
Percentage 0-1% Fix leaks or faulty sprinklers
within 2 days. Yes

City of Milpitas 2025 Urban Water Management Plan DRAFT 105 Submittal Table 8-3 Retail: Demand Reduction Actions - Water Code Section 10632(a)(4)(B) and (E) Yes Is the Supplier completing this table using the standard six levels? (yes/no) Shortage
Level
Demand
Reduction
Actions
How much is this going to reduce
the shortage gap? Additional Explanation or
Reference
Penalty,
Charge, or
Other
Enforcement?
Volume or
Percentage
Shortage Gap
Reduction Value
(MG)
5 Landscape -
Prohibit all
landscape
irrigation
Percentage 5-20% All irrigation is prohibited. Yes
5 Landscape -
Prohibit
certain types
of landscape
irrigation
Percentage 0-1% Watering of all golf course
areas is prohibited. Yes
5 Landscape -
Prohibit
certain types
of landscape
irrigation
Percentage 0-1%
Watering of parks, school
grounds, and recreation
fields is prohibited, except
for rare plant or animal
species.

Yes
6 Other -
Customers
must repair
leaks,
breaks, and
malfunctions
in a timely
manner
Percentage 0-1% Fix leaks or faulty sprinklers
within 1 day. Yes
6 Other Percentage 0-50% Water use for public health
and safety purposes only. Yes
6 Landscape -
Prohibit all
landscape
irrigation
Percentage 0-5%
The City may shut off all
non-essential water
services. All irrigation is
prohibited.

Yes
6 CII - Other
CII
restriction or
prohibition
Percentage 0-15%
Water for commercial,
manufacturing, or
processing purposes shall
be reduced in volume by
up to 50% or exceeded if
necessary for public health
and safety purposes.

Yes
6 Other Percentage 0-70%
Water use for public health
and safety purposes only.

Customer rationing may be
implemented.

Yes

City of Milpitas 2025 Urban Water Management Plan DRAFT 106 9 DEMAND MANAGEMENT MEASURES
Lay Description
This chapter communicates the City of Milpitas’s efforts to promote conservation , reduce demand on water supplies and implement several Demand Management Measures (DMMs) including similar information from Valley Water, the City’s wholesaler.

As a member of the California Water Efficiency Partnership (CalWEP) the City continues to implement numerous DMMs in the form of conservation programs, most of which builds from and meets the goals of the last iteration of the CUWCC’s foundational and prog rammatic Best Management Practices (BMPs). The California Water Efficiency Partnership (CalWEP) was formerly known as the California Urban Water Conservation Council (CUWCC). Due to substantial changes in social, economic, environmental, regulatory, and political conditions over its 25 years of existence, the CUWCC underwent an organizational transformation in 2016 and subsequently sunset. It was relaunched in 2017 as the California Water Efficiency Partnership (CalWEP).

The City’s conservation program is guided by a mix of agency and City policy directives and state and local water efficiency requirements that have evolved over time. On the state level, these shifted from meeting BMPs to the state per capita water reducti on targets set by the Water Conservation Action of 2009 (SB X7 -7), to the more recent water efficiency targets mandates by AB 1668 and SB 606. Urban water retailers will need to meet these new mandates starting in 2027 . The City has been implementing conse rvation measures for decades. Through continued efforts to promote conservation and educate its residents and retail customers on efficient and appropriate uses of water, the City was able to exceed its SB X7 -7 target. As mentioned in Chapter 5, the City’s 2020 confirmed GPCD target was 146; however, its actual 2020 GPCD was 108.

In addition, t he City participates in all rebates and offers that are available from Valley Water including cost - sharing on the landscape rebate program, which allows residential customers to receive higher rebate amounts.

Due to this participation with Valley Water, the City does not currently participate in any Bay Area Water Supply & Conservation Agency (BAWSCA) rebate programs. However, the City does work with BAWSCA to hold Landscape Education Workshops (typically 3 classes each period).

9.1 Demand Management Measures for Retail Suppliers
This section describes the City’s planned efforts in implementing various conservation measures to meet its water use targets and its future plans for achieving its water use objectives.

9.1.1 Water Waste Prevention Ordinances
The City’s water waste prevention ordinance is in place and prohibitions are included in response to shortages.

The ordinance also reflects permanent restrictions which remain in effect even when the City is not experiencing a water shortage. The City’s current Ordinance 240.7 can be found in the City’s WSCP; see Appendix D of this Valley Water Standard Text
Valley Water has made significant investments to manage demands for water, and water savings from conservation and stormwater capture were about 87,000 acre-feet per year (AFY) in 2025, compared to a 1992 baseline. Valley Water’s long -term conservation goals are to achieve 99,000 AFY by 2030, 110,000 AFY by 2040, and 126,000 AFY by 2050. Currently, Valley Water has more than 20 active water conservation programs in place to reduce water consumption in homes, businesses, schools, government facilities, and agriculture. These programs are designed to achieve sustainable, long -term water savings and are implemented regardless of water supply conditions.

City of Milpitas 2025 Urban Water Management Plan DRAFT 107 UWMP. The City plans to update its water waste ordinance shortly after the adoption of the 2025 WSCP to include the prohibition of irrigating nonfunctional turf with potable water as a permanent water waste restriction.

9.1.2 Metering
All the City’s customer accounts are metered. As of 2024, 99% of meters that were installed in the City’s service area are Advanced Metering Infrastructure (AMI) which allow for near real-time metering of water use. The City maintains water use information for residential, commercial, industrial, institutional/governmental, and irrigation (potable and recycled) water users. Table 4-1 describes actual water deliveries for 2025.

9.1.3 Conservation Pricing
The City’s water rate structure is consistent with a recent consultant report and current ordinance. The uniform rates for the quantity charges are billed bimonthly and imposed per hundred cubic feet for metered water service, based on the size of the water meter. The rates and effective dates for the bimonthly fire service charges are determined based on the size of the fire service. Current rates can be found in the City Ordinance. 58 9.1.4 Public Education and Outreach
The City conducts its conservation program in conjunction with resources provided by Valley Water and BAWSCA. Programs implemented through partnerships with these agencies may include free showerheads and aerators, the Irrigation Hardware Upgrades Rebate Program, Landscape Conversion Rebate Program, Rainwater Capture Program, Graywater Laundry -to-Landscape Rebates , free Water Wise Outdoor Surveys and free Landscape Education workshops. The City contributes to these programs indirectly through wholesale water costs and wastewater treatment purchases. The City cost -shares with Valley Water for the Landscape Rebate program to provide additional funds to participants applying for the landscape conversion, laundry-to-landscape graywater, and rainwater harvesting rebates. The City also distributes educational information to schools, various fairs and other public events. Conservation-related workshops, resources, and drought information are also posted on the City’s website and social media channels.

9.1.5 Programs to Assess and Manage Distribution System Real Loss City maintenance crews investigate and repair water leaks, the majority of which occur in service laterals. Long- term plans to reduce water loss include the following:
• Replace existing meters with smart meters
• Implement supervisory control and data acquisition system • Replace selected water pipe with upgraded design criteria to withstand seismic events • Maintain an active cathodic protection system

9.1.6 Water Conservation Program Coordination and Staffing Support As part of the City’s response to the drought, the City established a Water Conservation Program. The program was structured to facilitate and respond to reports of water waste and violations of local water use restrictions.

It also provides an opportunity to educate home and business owners on water conservation. To facilitate the

58 Ord. No. 120.50, § 2, April 18, 2023.
https://library.municode.com/ca/milpitas/codes/code_of_ordinances?nodeId=TITVIIIPUWO_CH1WASY_S6WASECH_VIII - 1-6.13QUCH

City of Milpitas 2025 Urban Water Management Plan DRAFT 108 community’s ability to report water waste, various reporting options were developed including email, a water– waste hotline, the City’s website and through a mobile application. The Water Conservation Coordinator is:

Samantha Vergara
455 E Calaveras Blvd
Milpitas, CA 95035
408-586-2617
[email protected]

9.2 Planned Implementation to Achieve Water Use Targets As discussed in Chapter 5, the City of Milpitas has met its water use targets. The City will continue to promote Valley Water’s conservation programs and BAWSCA’s landscape classes to the community.

9.3 Members of the California Water Efficiency Partnership Until 2022, t he City was not a member of the California Water Efficiency Partnership (CalWEP) formerly the Urban Water Conservation Council (Council). However, the City has submitted annual reports to the Council in accordance with the “Memorandum of Understanding Regarding Urban Water Conservation in California,” dated September 1991, as amended. The City is now a member of CalWEP, as of 2022, and attends workshops and working group meetings to stay informed of regulatory requirements and collaborate with other member agencies to develop and share Best Management Practices.

9.4 Urban Water Use Objectives
The City , as an Urban Water Retail Supplier, has included information on their annual Urban Water Use Objectives (UWUOs) in Chapter 5 . Valley Water and the City offer a suite of programs, described in detail throughout this chapter, that will help the City meet and calculate the UWUO and fulfill CII BMP requirements.

The following table describes the City’s programs that will assist the City in meeting its UWUO through both direct measures: programs/activities that result in directly quantifiable water savings; and indirectly: programs that provide resources promoting water efficiencies to the public that are impactful but not directly measurable.

City of Milpitas 2025 Urban Water Management Plan DRAFT 109 Table 9-1. Programs to Assist in Meeting Water Use Objectives WUO Component Calculation Program Impact
Indoor
Residential
Population and
GPCD standard
Direct Impact
• Plumbing Devices
Giveaways
Indirect Impact
• Water efficiency surveys
• Customer water portal
• Public and School
Education
Direct Impact: Increase in
indoor residential
efficiencies and reductions
through GPCD use
Indirect Impact: Provide
information, resources, and
education to promote
efficiencies in the home
Outdoor
Residential
Irrigated/irrigable
area measurement
and a percent factor
of local ETo
Direct Impact
• Landscape Conversion
• Weather-Based
Irrigation Controller
upgrade
• In-line drip conversion
Indirect Impact
• Landscape Surveys
• Public and School
Education
Direct Impact: Increase
outdoor residential
efficiencies and reductions
of gallons per ft2 of
irrigated/ irrigable area use
Indirect Impact: Provide
information, resources, and
education to promote
efficiencies in the landscape
Outdoor
Dedicated
Irrigation Meters
Irrigated/irrigable
area measurement
and a percent factor
of local ETo
Direct Impact
• Turf Removal
• Landscape incentives
Indirect Impact
• Public and School
Education
• Landscape Survey
• Customer landscape
water portal
Direct Impact: Increase
outdoor residential
efficiencies and reductions
of gallons per ft2 of
irrigated/ irrigable area used
Indirect Impact: Provide
information, resources, and
education to promote
efficiencies in the landscape
Water Loss
Following the
AWWA M36 Water
Audits and Water
Loss Control
Program, Fourth
Edition and AWWA
Water Audit
Software VI
Direct Impact
• Water Balance
Validation
• Customer Meter
Accuracy Testing
• Distribution System
Pressure Surveys
• Distribution System Leak
Detection
• No-Discharge
Distribution System
Flushing
• Water Audit
Compilation
• Component Analysis
Direct Impact: Identify areas
of the distribution system
that need repair,
replacement, or other
action

City of Milpitas 2025 Urban Water Management Plan DRAFT 110 10 PLAN ADOPTION, SUBMITTAL AND IMPLEMENTATION
Lay Description
Procedures for adopting and implementing the UWMP in a transparent and stakeholder-accessible manner are essential for good governance of water resources. It is important for customers to have the opportunity to understand how water is managed and how reliable it is. Supporting a public process through adequate notifications and public hearings also allows the interes ted public to submit comments and suggest revisions affecting reliability and future investments in local water management. Adopting the plan makes it part of the formal management of the Supplier, which is often important for justifying investment decisio ns and potential rate restructuring over the near- and long-term. In this chapter, information is provided on the processes the City of Milpitas followed for the public hearing, adoption, and submission of the UWMP and its public availability, plan implementation and how to amend an adopted UWMP.

This 2025 UWMP also includes a Water Shortage Contingency Plan (WSCP) as required under the provisions of AB 11X of (1991) and addresses changes required by subsequent legislation including the Water Conservation Act of 2009 (SB X7 -7). The WSCP also incorporates the water conservation initiatives that the City has implemented.

If any update is made to this 2025 UWMP or the WSCP, the City will follow the amendment process outlined in Section 10.8 of this UWMP.

As required by Section 10621 (a) of the Water Code, the City will update the UWMP again for the 20 30 UWMP process.

10.1 Notice of Plan Preparation
This section describes the notice distributed to cities, the county and other entities by the City of Milpitas. The notice included the location where the 2025 UWMP could be viewed, the UWMP revision schedule and the City’s contact information. A copy of this notice is included in Appendix B. Table 10-1 lists the specific entities notified.

City of Milpitas 2025 Urban Water Management Plan DRAFT 111 Table 10-1. Notification to Cities and Counties
Submittal Table 10-1 Retail: Notification to Cities and Counties - Water Code Section 10621(b) and 10642
Entity Name 60 Day
Notice
Notice of
Public Hearing
City of Brisbane Yes
City of Burlingame Yes
City of Daly City Yes
City of East Palo Alto Yes
City of Foster City Yes
City of Gilroy Yes
City of Hayward Yes
City of Hillsborough Yes
City of Menlo Park Yes
City of Millbrae Yes
City of Morgan Hill Yes
City of Mountain View Yes
City of Palo Alto Yes
City of Redwood City Yes
City of San Bruno Yes
City of San Jose Yes
City of Santa Clara Yes
City of Sunnyvale Yes
Alameda County Water District Yes
BAWSCA Yes
California Water Service Yes
Coastside County Water District Yes
Great Oaks Water Company Yes
Mid-Peninsula Water District Yes
Milpitas Chamber of Commerce Yes
Milpitas Unified School District Yes
North Coast County Water District Yes
Purissima Hills Water District Yes
SFPUC - Wholesaler Yes
San Jose Water Yes
Stanford University Yes
Valley Water - Wholesaler Yes
Westborough Water District Yes
City of Brisbane Yes
County Name 60 Day
Notice
Notice of
Public Hearing
Santa Clara County Yes
NOTES: 60-day notice sent out via email February 11, 2026. Notice of public hearing posted May 22 and 29, 2026.

City of Milpitas 2025 Urban Water Management Plan DRAFT 112

10.2 Notice of Public Hearing
The public was notified on May 22 and May 29, 2026 prior to the public hearing that the City would be reviewing and considering amendments to the UWMP. The public hearing was placed in a local newspaper for two successive weeks (14 calendar days) or two separate one -week timeframes with at least five days between publication dates, as prescribed in Government Code Section 6066.59 This notice included the time and place of the hearing as well as the location where the UWMP was available for public inspection. Notification came through a display advertisement in The Milpitas Post and by posting the 2025 UWMP on the City’s website (https://www.milpitas.gov/752/Urban-Water-Management-Plan) by May 22, 2026.

A public hearing before the City Council was held on June 9, 2026 , to discuss and receive comments/input regarding the City’s 2025 UWMP and WSCP prior to its adoption. The public hearing was advertised in The Milpitas Post 14 days and 7 days prior to the hearing. See Appendix C for a copy of the newspaper notice.

10.3 Implementation over the Past Five Years
The following water DMMs have been implemented to achieve water use targets. The City communicates these programs to all Milpitas residents through newsletter distribution, local advertisements, and City media.

Residential Surveys
Valley Water’s residential survey program includes educating the customer on how to read a water meter; checking flow rates; installing low-flow devices; checking for leaks; checking the irrigation system for efficiency; measuring landscaped area; developing an efficient irrigation schedule for different seasons; and providing the customer with evaluation results, water savings recommendations, and other educational materials. Valley Water increased efficiency and participation by using landscape measuremen ts from this program as an initial qualifying step for the Landscape Rebate Program.

Water Wise Outdoor Survey
Valley Water’s Water Wise Outdoor Survey Program offers a free, comprehensive consultation from a trained irrigation professional to single -family and small multi- family sites with a working irrigation system. The consultation includes evaluating the irrigation system, flagging issues onsite, irrigation scheduling assistance, identifying rebate programs for which participants may also qualify, and creating a custom report detailing the survey findings.

Water Use Reports
Water use reports have been proven effective at encouraging residents to save water and when combined with Advanced Metering Infrastructure, can inform residents about water leaks quickly. In FY 2014, Valley Water started a program to share costs with the local water retailers on home water use reports.

The City has a cost-share agreement with Valley Water to provide water use reports to its residential customers.

Water use reports include information about the customer’s water use during the previous bill period, the customer water use portal, links to rebate information and educational materials, and tips to conserve water.

Residential Plumbing Retrofit
Valley Water has provided free low -flow showerheads and faucet aerators to Santa Clara County residents via its water retailers, residential water surveys, public events, and the Online Shopping Cart program. City staff offer these free water-saving devices to Milpitas residents via distribution at City-sponsored events, City media, and residential newsletters. In addition to the showerheads and aerators dire ctly distributed by Valley Water,

59 California State Legislature. (1949). Government Code Section 6066. http://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=GOV&sectionNum=6066

City of Milpitas 2025 Urban Water Management Plan DRAFT 113 the City has distributed thousands of low -flow showerheads and aerators. The City also offers a variety of free water conservation tools, such as low-flow showerheads, aerators, hose nozzles, moisture meters, and more.

System Water Surveys, Leak Detection and Repair
All connections within the City are metered, except for some City maintenance activities such as street sweeping, fire flow testing, and sewer vactor truck filling. To minimize leaks from residential, business, and irrigation connections, City maintenance crews replace all leaking meters, repair water service and main leaks, and calibrate compound or multi-head meters annually. The City will continue t o conduct its meter calibration and replacement program.

From 2019 to 2023, the City worked with its water loss management consultant, E -source, to conduct a full - system leak detection survey. During the surveys, E -Source technicians listened to all accessible infrastructure and fittings, including customer meters, fire hydrants, blow-off valves, and backflow preventers, to ensure that all acoustically detectable leaks on the survey route were identified. This 2025 UWMP includes water loss audit distribution system losses for the past f ive years (see Section 4.3). The City is developing a large meter testing program to better understand meter accuracy. In addition, the City participates in the Water Loss Management Plan through BAWSCA’s subscription program with E -source to compile validate water loss audits and identify future actions that can be taken to further reduce water loss. Additional water loss management tasks have included: large meter testing, real loss component analyses, billing data analyses, and meter testing strategy development.

Metering with Commodity Rates for All New Connections and Retrofit of Existing Connections All water connections in the City are metered, and separate irrigation meters, called Dedicated Irrigation Meters (DIMs) are required for non-residential customers and new large-scale multi-family developments. Commercial, industrial, and institutional customers are required to have fire sprinkler systems with separate meters. The City has also installed separate meters for recycled water services. Rebates for the installation of submeters, as well as switching from a mixed -use meter to a dedicated landscap e meter, are offered through Valley Water. The submeter program provides $150 per submeter installed at multi-family housing complexes. Valley Water plans to continue to offer this program in the future to reach the region’s long -term water conservation go als. The City will continue to install and read meters for all new services.

Landscape Rebate Program Conversion & Rainwater Harvesting Rebates Valley Water began to focus on water efficient landscapes by launching a program in early 2005. To increase program participation, the Valley Water Board approved doubling the maximum rebate from $1000 up to $2,000 for residents and from $10,000 up to $20,000 for commercial sites in 2009. In January 2019, Valley Water added Rainwater Capture Rebates to the Landscape Rebate Program. The rebate cap for commercial, institutional, and multi-family (5 or more units) sites was increased to $50,000 on January 1, 2020. In July 2021, the turf conversion rebate was increased to $2 per square foot and the residential site cap was increased to $3,000. In response to an emergency regulation that prohibits the watering of non-functional turf areas at commercial, industrial, and institutional sites, issued by the State Water Resources Control Board in June 2022, Valley Water introduced a Lawn to Mulch rebate in July 2022 for commercial properties. Valley Water then increased the lifetime cap for CII sites to $100,000. Cost sharing agreements increase the rate per square foot and rebate cap in some areas.

Currently, Santa Clara County single family, multi-family and business properties with qualifying high water using landscape can receive rebates for converting to qualifying low water using landscape with a minimum of 50% qualifying plant coverage, 2 to 3 inches of mulch, and a conversion from overhead irrigation to drip/micro spray/bubbler or no irrigation.

The City has a cost -sharing agreement with Valley Water to increase the rainwater harvesting and landscape conversion rebate amounts for the City’s residential customers, and in July 2021, the City amended the cost - share agreement to provide additional fun ds. The amendment resulted in increased rebates: up to $4.00 per

City of Milpitas 2025 Urban Water Management Plan DRAFT 114 square foot for residential landscape conversions; up to $400 for installing a laundry -to-landscape graywater system; up to $75 per rain barrel and up to $600 for installing a rain garden.

Large Landscape Program
Valley Water has offered the Large Landscape Program since 2014 to provide large landscape water surveys and site-specific landscape water budgets. Participating landscape managers are provided with water-use analyses, scheduling information, in-depth irrigation evaluation, a site -specific water budget, and recommendations for affordable irrigation upgrades. Each site receives a detailed report upon completion of the survey . Participants and site stakeholders are encouraged to participate in the Landscape Rebate Program and are given access to the Waterfluence online portal. Through Waterfluence, property managers and landscapers can review water use information, recommendations to increase water use efficiency, and receive e-mail notifications for unusual irrigation events.

Public Information Programs
Valley Water operates an extensive public information program and associated school program, which provides materials, speakers, and outreach activities to the public. Outreach activities include publications and website development, public meetings, parti cipation at community events, multi -media campaigns, inter- agency partnerships, corporate environmental fairs, professional trade shows, landscaping workshops and seminars. In addition to Valley Water’s public information program, City staff also disseminates information to the public through City media, the City’s annual Consumer Confidence Report, and City sponsored events.

Since the COVID-19 pandemic, much public outreach has been focused on online content. Valley Water continues to apply community -based marketing approaches in their conservation outreach campaigns, highlighting local success stories from past rebate program participants.

School Education Programs
Valley Water has a full- time staff to coordinate the school education programs. Valley Water provides free classroom presentations, puppet plays, and tours of district facilities to schools within the county. The objective is to teach students about water conservation, water supply, watershed stewardship and flood protection. Valley Water also provides school curricula to area educators, including workbooks and videos, as well as hands -on training for teachers. Students range from pre-kindergarten through college. Included in the educational services is Project WET (Water Education for Teachers) to train teachers how to lead their own classroom activities to independently educate students on water-related topics into the future.

Conservation Programs for Commercial, Industrial, and Institutional (CII) Accounts Water Efficient Technology Rebate Program
The Water Efficient Technology Rebate (WET Rebate or WET Program) provides rebates for process, technology, and equipment retrofits that save water at CII and multi-family properties. Qualifying retrofit projects that meet program requirements are eligible for a rebate of either $4 per hundred cubic feet (CCF) of water saved annually or up to 100% of equipment costs excluding taxes and labor, whichever is less, up to $100,000. To qualify, projects must save at least 100 cubic feet of water annually. Examples of eligible projects include ozone laundry systems, cooling towers efficiency upgrades, onsite water reuse, water softeners, and any other equipment that results in measurable water savings, including customized equipment. Cost sharing agreements increase the rate and maximum rebate in some areas. In 2023, eligibility for WET was expanded to include multi-family properties, such as condominium, apartment, and townhome complexes.

The WET Rebate continues to be one of Valley Water’s most cost- effective programs in meeting the region’s long-term water conservation goals.

Commercial Toilet and Urinal Program

City of Milpitas 2025 Urban Water Management Plan DRAFT 115 Valley Water has been replacing inefficient toilets in commercial, industrial, and institutional (CII) sites since 1994. The CII toilet rebate programs have frequently been offered in tandem with various iterations of high - efficiency urinal (HEU) programs, HET and HEU direct install programs, and retrofit programs for urinal valve installation.

In May 2021, Valley Water launched the Fixture Replacement Program (FixRP), a direct-install initiative focused on replacing inefficient indoor plumbing fixtures with high -efficiency, WaterSense-certified models in multi- family residential and commercial properties. The program concluded in April 2025 and has since been replaced by the Direct Retrofit Indoor Plumbing (DRIP) Program, which expands eligibility to include single-family homes.

Commercial Faucet Aerator Program
Since 2010, Valley Water has offered free 0.5 gallon per minute faucet aerators to qualifying businesses and schools. Free faucet aerators can be ordered through Valley Water’s Online Shopping Cart.

Pre-Rinse Spray Valve Program
Pre-rinse spray valves are designed to remove food waste from dishes prior to dishwashing and are often used in commercial kitchens. In previous years, Valley Water partnered with other agencies to offer a direct installation program for high-efficiency pre-rinse spray valves (PRSVs). In 2010 Valley Water purchased a quantity of PRSVs with a flow rate of 1.15 gallons per minute for distribution to commercial sites, especially those identified through Valley Water’s previous CII Water Survey Program. Valley Water plans to continue distributing these devices for free through their Online Shopping Cart program to meet the region’s long -term water conservation goals.

Commercial Indoor Water Survey Pilot Program
Valley Water initiated the Commercial Indoor Water Use Survey Pilot Program (CIW Survey Pilot) in FY 2024 to support state’s conservation requirements under Making Conservation a California Way of Life (AB 1668/SB 606) and to engage with hard -to-reach comm ercial, industrial, and institutional (CII) customers. Developed in partnership with a subset of water retailers, the pilot sought to improve understanding of CII indoor water use, update water savings assumptions, and strengthen coordination among agencie s and customers. While initial outreach yielded limited participation, revised efforts resulted in modest engagement and valuable insights, highlighting challenges related to customer contact data, data- sharing constraints, technology gaps, and outreach timing.

In FY 2025, Valley Water strengthened and expanded the pilot, refining outreach strategies and partnering with new retail partners.

Wholesale Agency Assistance Program
Valley Water, through a unique cooperative partnership with its retailers, offers regional implementation of a variety of water conservation programs to permanently reduce water use in Santa Clara County. It continues to collaborate with water retailers to implement various water conservation programs on a regional basis, ensuring its long-term water supply reliability goals are met as well as assisting its water retailers in meeting their goals.

Conservation Coordinator
As noted in Section 9.1.6, as part of the City’s response to the most recent drought, the City established a Water Conservation Program.

Water Waste Prohibition
In May 1994, the City adopted Water Conservation Ordinance No. 240, which describes water use prohibitions and was last amended August 5, 2021. Ordinance 240.7 can be found in the City’s WSCP (see Appendix D of this UWMP). The City plans to update its water conservation ordinance shortly after the adoption of 2025 WSCP to include the prohibition of irrigating nonfunctional turf with potable water as a permanent water waste restriction.

City of Milpitas 2025 Urban Water Management Plan DRAFT 116

10.4 Public Hearing and Adoption
This section details the public hearing and adoption processes for the 2025 UWMP and WSCP.

10.4.1 Public Hearing
The public hearing allowed for community input, consideration of economic impacts and adoption of a method for determining the City’s urban water use target.

10.4.2 Adoption
This 2025 UWMP was presented to the City Council for review and adopted on June 9, 2026, thereby superseding the existing plan prepared in 2020. The adopted 2025 UWMP has been filed with the Water Efficiency Office in the Department of Water Resources, the California State Library, the Bay Area Water Supply & Conservation Agency, the City offices, Santa Clara County and the Cities of Brisbane, Burlingame, Daly City, East Palo Alto, Foster City , Gilroy, Hayward, Hillsborough, Menlo Park, Millbrae, Morgan Hill, Mountain View, Palo Alto, Redwood City, San Bruno, San Jose, Santa Clara and Sunnyvale, as required by law, and will be used by the City staff during the current five-year planning cycle.

A copy of the resolution adopting the 2025 UWMP is provided in Appendix G.

10.5 Plan Submittal
To satisfy California Water Code Sections 10635(c), 10644(a)(1) and (2) and 10645(a) and (b), within 30 days of adoption, the City submitted a copy of the 202 5 UWMP and WSCP to DWR, the California State Library Government Publications Section (Sacramento) and to any city or county to which the City provides water.

10.5.1 Submitting a UWMP and WSCP to DWR
To satisfy DWR requirements, all UWMPs and WSCPs must be submitted to DWR within 30 days of adoption and prior to July 1, 2026. The City met this requirement as outlined in the following sections.

10.5.2 Electronic Data Submittal
The City submitted its 2025 UWMP and WSCP to DWR electronically. Documentation confirming the City’s 2025 UWMP and WSCP submittal can be found in Appendix H.

10.5.3 Submitting a UWMP to the California State Library The City submitted a CD or hard copy of its adopted 202 5 UWMP to the California State Library within 30 days of adoption.

10.5.4 Submitting a UWMP to Cities and Counties
The City submitted a copy of its adopted 2025 UWMP to any city or county served by the City within 30 days of adoption.

10.6 Public Availability
Within 30 days after filing the 2025 UWMP and WSCP with DWR, the documents were made available for public review on the City’s website.

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10.7 Notification to Public Utilities Commission
Per Water Code Section 10621(c ), Suppliers that are regulated by the California Public Utilities Commission (CPUC) must submit their UWMP and WSCP to the CPUC as part of its general rate case filings. Since this was not applicable to the City, the plans were not submitted to the CPUC.

10.8 Plan Implementation
The City will implement this plan adopted pursuant to this chapter in accordance with the schedule set forth in this plan.

10.9 Amending an Adopted UWMP or WSCP
Should any changes be made to the 202 5 UWMP and/or the WSCP, per Water Code Sections 10621(d) and 10644(a)(1), within 30 days after adoption, the City must submit copies of the amendments or changes to DWR, the California State Library and any city or county to which the City supplies water.

10.9.1 Amending a UWMP
If the City amends the adopted 202 5 UWMP, each of the steps for notification, public hearing, adoption and submittal must also be followed for the amended UWMP.

10.9.2 Amending a WSCP
Specific to Water Code Section 10644(b), if the City revises its WSCP after DWR has approved the 2025 UWMP, the City must submit to DWR an electronic copy of the revised WSCP within 30 days of adoption.

City of Milpitas 2025 Urban Water Management Plan DRAFT 118 11 REFERENCES
All links below were accessed in May 2026 unless otherwise indicated.

Ackerly, David, Andrew Jones, Mark Stacey, Bruce Riordan (University of California, Berkeley). (2018.) San Francisco Bay Area Summary Report. California’s Fourth Climate Change Assessment. Publication number:

CCCA4-SUM-2018-005. https://www.energy.ca.gov/sites/default/files/2019-11/Reg_Report-SUM-CCCA4-2018- 005_SanFranciscoBayArea_ADA.pdf
Association of Bay Area Governments (ABAG). (2021). Draft Regional Housing Needs Allocation (RHNA) Plan:

San Francisco Bay Area, 2023–2031. https://abag.ca.gov/sites/default/files/documents/2021-05/ABAG_2023- 2031_Draft_RHNA_Plan.pdf
Bay Area Water Supply and Conservation Agency & San Francisco Public Utilities Commission. (2009). Water Supply Agreement (WSA) between the City and County of San Francisco and Wholesale Customers (July 2009). https://bawsca.org/uploads/userfiles/files/Plans%20and%20Reports/FINAL_WSA_with_Attachments.pdf Bay Area Water Supply and Conservation Agency (BAWSCA). (2019). BAWSCA Capital Improvement Planning Comparison Study (September 2019, p. 1).
http://bawsca.org/uploads/userfiles/files/CIP%20Comparison%20Study%20_09-2019_V_Final_9_10_19.pdf Bay Conservation and Development Commission (BCDC). (2020). Adapting to Rising Tides, Bay Area. http://www.adaptingtorisingtides.org/project/art-bay-area/.

Cal-Adapt. (n.d.). CMIP5 Local Climate Change Snapshot Tool. https://cmip5.cal-adapt.org/tools/local-climate- change-snapshot
California Department of Finance. (2025). E-5 Population and Housing Estimates for Cities, Counties and the State — January 1, 2021-2025.
https://dof.ca.gov/forecasting/demographics/estimates/e-5-population-and-housing-estimates-for-cities-coun ties-and-the-state-2020-2025/
California Department of Water Resources (DWR). (2006). Progress on Incorporating Climate Change into Planning and Management of California’s Water Resources, Technical Memorandum.

California Department of Water Resources (DWR). (2008). Managing an Uncertain Future: Climate Change Adaptation Strategies for California’s Water. https://digitalcommons.csumb.edu/hornbeck_usa_3_d/63/ California Department of Water Resources (DWR). (2010). Climate Change Characterization and Analysis in California Water Resources Planning Studies. https://cawaterlibrary.net/document/climate-change- characterization-and-analysis-in-california-water-resources-planning-studies-2/ California Department of Water Resources (DWR). (2016). Methodologies for Calculating Baseline and Compliance Urban Per Capita Water Use. https://cadwr.app.box.com/s/5rbv5gjm881dxonycnb7u2253a0l6e8l California Department of Water Resources (DWR), et al. (2017). Making Water Conservation a California Way of Life, Implementing Executive Order B-37-16. https://cawaterlibrary.net/wp- content/uploads/2017/06/20170407_EO_B-37-16_Final_Report.pdf California Department of Water Resources (DWR). (2021). Urban Water Management Plan Guidebook 2020. https://water.ca.gov/Programs/Water-Use-And-Efficiency/Urban-Water-Use-Efficiency/Urban-Water- Management-Plans
California Department of Water Resources (DWR). (2024). Climate Action Plan Phase 1: Greenhouse Gas Emissions Reduction Plan Update 2023. https://water.ca.gov/-/media/DWR-Website/Web- Pages/Programs/All-Programs/Climate-Change-Program/Climate-Action-Plan/Files/Exhibit-C-CAP-Phase-1- Update-2023.pdf