TO: HONORABLE MAYOR
AND CITY COUNCIL
FROM: Jeff Provenzano
SUBJECT: Status Report on the
Purified Water Project
DATE: July 17, 2025
Approved Date:
7/30/25
RECO
MMENDATION
Vall
ey Water Board and the City of San José Mayor and City Council receive the status report on the purified water project and provide feedback on the development of a potable reuse project.
BACKGRO
UND
Cl
imate change makes our community more vulnerable to extreme weather conditions, including periods of long-term drought and more intense wet-weather events. Valley Water is currently updating its Water Supply Master Plan 2050 to ensure a reliable supply of potable water for our communities in the future. Investing in potable reuse was found to be an effective way to address projected shortages, particularly in drought periods. In January 2023, Valley Water, the City of Santa Clara, and the City of San José executed a Letter of Intent for Collaborating on the Expansion of Recycled and Purified Water in Santa Clara County. This collaboration involves leveraging the treated wastewater from the San José-Santa Clara Regional Wastewater Facility for potable reuse. On November 17, 2023, the Valley Water Board and the San José City Council provided the following guidance to staff to ensure the development of collaborative win- win solutions that meet Valley Water, City of Santa Clara, and City of San José’s needs and improve the community’s drought resilience with respect to water supply. • Conf
irmed support for aggressively pursuing a joint project to meet local water supply needs, including both a demonstration and full-scale potable reuse project that is the largest size practicable within funding, environmental, and technical constraints.
• Confirmed support for development of a feasibility study, demonstration facility, and institutional arrangements, including land lease and wastewater availability agreements, within two years.
JOINT CC/VW AGENDA: 8/19/25
FILE: 25-821
ITEM: 6.2
HONORABLE MAYOR AND CITY COUNCIL
July 17, 2025
Subject: Status Report on the Purified Water Project
• Confirmed support for a coordinated public outreach program to ensure the success of a direct potable reuse project.
• Communicate twice-yearly or as-needed updates to the Joint Recycled Water Policy Advisory Committee.
Two City staff funding agreements have been executed: Valley Water will reimburse the City for City staff work supporting the potable reuse facilities at up to $1 million per year. As a result, the Valley Water and City team has been collaborating regularly. This memorandum provides an update on the progress since the last joint Valley Water Board and City Council meeting and presents next steps.
ANALYSIS
The Direct Potable Reuse (DPR) Regulations were finalized by the State Water Resources Control Board on October 1, 2024. These DPR regulations permit the delivery of advanced purified water directly to consumers or delivery to a water treatment facility. Valley Water is currently conducting an environmental review for a DPR Demonstration Facility in compliance with the California Environmental Quality Act (CEQA). If CEQA is approved, Valley Water plans to implement this collaborative potable reuse project in two phases.
1. Demonstration Facility: Based on discussions with technical experts and regulators, a demonstration facility will expedite a full-scale advanced water purification facility, reduce risks, and project costs for a full-scale facility.
2. Full-Scale Facility: A full-scale advanced water purification facility to provide up to 24,000 acre-feet per year of drought-resilient potable water supply, following completion of CEQA.
In June 2025, the Valley Water Board and the City Council authorized the negotiation and execution of an option agreement to execute several agreements related to the Silicon Valley Advanced Water Purification Center and the proposed demonstration facility. The exercise of the option is conditioned on the completion of CEQA and certain conditions precedent.
Demonstration Facility
The demonstration facility will allow Valley Water to perform validation studies required for permitting a full-scale facility with the California Division of Drinking Water to ensure that pathogens and chemicals are removed to meet stringent DPR standards. In addition, the facility will help evaluate new technologies and train operators. A purified water learning center will provide public education and outreach to increase public support for the project.
HONORABLE MAYOR AND CITY COUNCIL
July 17, 2025
Subject: Status Report on the Purified Water Project
Valley Water staff is working on procuring a design consultant for the demonstration facility, amending an agreement with their CEQA consultant, and has conducted site visits to assist in developing the learning center.
Valley Water staff has also engaged with the California Division of Drinking Water to begin developing a testing plan for the demonstration facility and a regulatory roadmap for developing future permit applications for the full-scale facility.
Various California Division of Drinking Water required studies and reports to validate pathogen and chemical control, corrosion control, and wastewater and source control characterization will need to be prepared concurrently with the development of the full- scale facility’s 60 percent design. These investigations and studies must be completed prior to submitting the permit applications to the California Division of Drinking Water.
Thereafter, a public meeting will be held by the State Water Resources Control Board prior to the start of the construction stage. These regulatory processes ensure that multiple safeguards are in place, and the purified water produced by a DPR facility meets the stringent safety requirements for direct potable reuse.
Full-Scale Facility
Valley Water and City staff are developing the framework for the agreements required for a full-scale purification facility. The framework articulates the shared vision and addresses the main topics that the new agreements will need to address, including wastewater quality and quantity, facility pretreatment, reverse osmosis concentrate management, and source control.
In parallel, the City of Santa Clara and the City of San José are in conversation with the San Francisco Public Utilities Commission regarding the December 31, 2028, deadline for addressing the status of the currently interruptible potable water supplies. A critical project component is potential collaboration with the San Francisco Public Utilities Commission. Staff from Valley Water, City of Santa Clara, and City of San José held a workshop with staff from the San Francisco Public Utilities Commission to discuss developing a partnership for the full-scale DPR facility project on September 25, 2024. The outcome from the workshop resulted in all agencies being interested in partnering on an advanced purified water project.
The draft of the shared vision is:
Spurred by a sense of urgency and a shared commitment to a sustainable future providing safe, clean water for those who live and work in our region, we will implement an innovative, cost-effective, potable reuse program providing a locally-controlled, drought-resilient water supply. This project will be a model of inter-agency cooperation efficiently synergizing with existing resources in the interest of the public good and environmental stewardship.
Work on the long-term agreements for the full-scale advanced water purification facility has begun with a specific schedule to be mutually agreed to in a project charter that
HONORABLE MAYOR AND CITY COUNCIL
July 17, 2025
Subject: Status Report on the Purified Water Project
staff from the Valley Water, City of Santa Clara, and City of San José are developing collaboratively.
In addition to the project charter, an Exclusive Negotiation Agreement is being developed that would balance both parties’ interest. Valley Water is seeking assurance that the land for a full-scale facility will be available for a specified period of time before making significant upfront planning and study investments. The City would not be prohibited from maximizing the productive use of its land indefinitely. The Exclusive Negotiation Agreement will reserve the land needed for the full-scale facility for a specified period of time necessary to inform negotiation of agreements required for the full-scale facility. These agreements and the project charter will be presented to the Joint Recycled Water Policy Advisory Committee and the Treatment Plant Advisory Committee in the future.
Grants and Feasibility Study
Valley Water staff has procured engineering consultant assistance to develop a project feasibility study and provide future grant application support for the design and construction of a full-scale project. City staff were directly involved with the review and selection of the engineering consultant to provide this engineering and technical support. The San José-Santa Clara Purified Water Program Feasibility Study was previously estimated at approximately $1.5M and was recently funded with a $381,249 planning grant by the Bureau of Reclamation. Preparation of a feasibility study is a prerequisite for obtaining design and construction grants in the future, with Valley Water, City of Santa Clara, and City of San José committed to working together on its development.
Outreach
Public concerns over climate change and support for a resilient, sustainable water supply has been consistent since 2015. Valley Water continues outreach via public education and monitors the public pulse through public perception polls.
Tours of the existing Silicon Valley Advanced Water Purification Center have been in place since 2014 and are used to educate the public about potable reuse. In 2024, 1,768 people toured the Silicon Valley Advanced Water Purification Center.
A countywide poll was implemented by EMC Research, Inc. in August 2024 to collect data on public perception toward water reuse. The 2024 public perception poll included questions relating specifically to direct potable reuse and tested the impact of an increase to water rates on the favorability of purified water.
The following are key takeaways from the poll.
• Even with minor adjustments to question phrasing to make the concept of using advanced purified recycled water in the drinking water supply more relatable, public support has remained consistent with previous years.
HONORABLE MAYOR AND CITY COUNCIL
July 17, 2025
Subject: Status Report on the Purified Water Project
• There is a slight decrease in support when discussing specific methods of purified water use, such as indirect and direct potable reuse. • Overall perceptions of recycled water have become marginally less favorable. • The impact of cost concerns is mitigated when additional context is provided on the need, safety, and benefits of advanced purified recycled water for enhancing the drinking water supply.
• Older adults aged 50 and over demonstrated lower net support (lower support and higher opposition) than adults aged 18-49, which highlights the need for tailored outreach to older adults.
• Scientists and doctors are the most trusted messengers for purified water advocacy, followed by environmental organizations.
The Valley Water staff and City staff are coordinating on collaborative outreach opportunities to ensure public support for the project.
A Learning Center will be constructed to accompany the DPR demonstration facility.
The Learning Center is envisioned to be a destination where diverse visitors can learn about the wastewater process and the importance and safety of purified water. The Learning Center will provide physical spaces for education events and/or technical studies, as well as present opportunities for community members, elected officials, and other stakeholders to raise awareness and promote the importance of water reuse.
The Learning Center is a particularly significant investment to strengthen public support for direct potable reuse. The Learning Center, currently scheduled for construction in 2028 and opening in 2031, will be used to educate the public, including a target audience of students as young as 5
th grade, on recycled water and purified water and
the importance of these sustainable resources for Santa Clara County’s water portfolio.
To solidify support for purified water, the Learning Center will offer tours and the opportunity for each visitor to taste the purified water.
Next Steps
Staff requests input from the Valley Water Board and City Council to ensure development of win-win solutions that meet Valley Water’s and the City’s needs:
• Support the development of a project charter and exclusive negotiation agreement as necessary initial steps to guide studies and negotiate the institutional agreements required for a full-scale advanced water purification facility.
• Support for coordinated public education and outreach programs to ensure the success of a Direct Potable Reuse project.
• Support project updates twice a year or as needed to the Joint Recycled Water Policy Advisory Committee.
HONORABLE MAYOR AND CITY COUNCIL
July 17, 2025
Subject: Status Report on the Purified Water Project
COORDINATION
This memorandum has been coordinated with the City Attorney’s Office and the City Manager’s Budget Office. This memorandum will be presented to the San José-Santa Clara Regional Wastewater Facility Treatment Plant Advisory Committee meeting on August 14, 2025.
/s/
Jeff Provenzano
Director, Environmental Services
For questions, please contact Eric Dunlavey, Deputy Director for Regulatory Affairs and Purified Water, Environmental Services Department, at [email protected] or (408) 635-4017.