San Jose and Valley Water accept update on purified water plan, move ahead with demonstration facility

SAN JOSE — The City of San Jose and the Santa Clara Valley Water District on Aug. 19 accepted a joint staff update on plans to develop a direct potable reuse (DPR) program, including a pilot and a demonstration facility intended to pave the way for a full-scale purified water plant.

The two agencies' staffs outlined a multi-phase approach that begins with a pilot to gather regulatory data, continues with a demonstration facility and learning center, and — assuming required permits and funding — would culminate in a full-scale facility the agencies currently expect to begin operations in late 2035. Both the San Jose City Council and the Valley Water Board voted to accept the staff report at the joint meeting.

Valley Water and City of San Jose staff said the demonstration and pilot work is intended to reduce permitting risk for a large project that staff estimated will cost nearly $2,000,000,000. Kirsten Strouff of Valley Water said the demonstration facility will validate treatment performance to meet direct potable reuse regulatory requirements and support operator training; it will also host a learning center for public outreach. Eric Dunlavy of the City of San Jose described an exclusive negotiation agreement under development that would reserve the land envisioned for the full-scale facility for a limited time while the agencies complete planning and agreements.

Staff described where the project stands: a planning phase, a released RFP for a design consultant for the demonstration facility, amended agreements that allow the DPR demonstration to be built at the existing Silicon Valley Advanced Water Purification Center, and a program feasibility study estimated at about $1,500,000 (staff said the U.S. Bureau of Reclamation provided roughly $380,000 toward that study). The agencies are also meeting with regulators on a testing plan for the demonstration facility and a regulatory road map for future permit applications.

Project scope and timeline details cited at the meeting included: - A planning-stage pilot and demonstration facility sequence, with the demonstration and learning center site described as about 2 acres and an associated parking lot of roughly 1 acre proposed to be built by Microsoft. - An estimated target for future full-scale capacity of roughly 24,000 acre-feet per year of purified water (staff said that would require roughly 30 million gallons per day of source water). - A full-scale facility currently shown in the agencies' planning documents to be in the later 2030s, with an operational target cited as “late 2035.”

Staff emphasized the demonstration project's regulatory purpose: to perform validation studies required for DPR permits, demonstrate pathogen and chemical removal, evaluate advanced treatment technologies, and develop operator training and public education materials. Staff also said the demonstration will be used to support permitting of a full-scale facility by reducing technical uncertainty.

On outreach and public acceptance, Valley Water staff summarized polling and education efforts. Staff said recent polling in 2024 measured public attitudes toward DPR and found overall support remained similar to previous years but showed somewhat lower support among adults 50 and older and slightly less favorable responses when questions asked about specific methods (indirect versus direct potable reuse). Staff said scientists and doctors rate highest as trusted messengers and that public tours and the proposed learning center (targeted for construction in 2028 per staff) are key outreach tools. Civic engagement manager Kristen Yasukawa said printed outreach materials are produced in four languages (English, Spanish, Vietnamese and Mandarin) and that the agencies are exploring prerecorded translated tours.

Councilmembers and directors voiced broad support at the meeting. Councilmember Kamay said, “I am so delighted that we've come to this point,” and multiple councilmembers thanked agency staff and directors for years of work advancing recycled and purified water as a drought‑resilient supply. Councilmembers and directors asked about costs, grant opportunities and technical risks; staff said the project is expensive, that the feasibility study is intended to make the program competitive for federal grants (staff cited U.S. Bureau of Reclamation grant opportunities), and that the DPR regulatory framework in California is new and requires extensive validation studies.

Questions about microplastics were raised. A councilmember asked whether treated water would be tested for microplastics and how reverse osmosis concentrate would be handled. Staff said they have conducted microplastics studies and said treated (finished) water intended for drinking would not contain microplastics based on testing, while the concentrate stream (reverse osmosis reject) will have to be managed carefully because it concentrates contaminants and must be disposed of or treated in a way that avoids harming sensitive bay habitat.

Both legislative bodies voted to accept the staff report. On the San Jose City Council side, a councilmember moved to accept the report and the council voted to accept the staff update (motion passed unanimously). The Valley Water Board also moved and approved a motion to receive the staff report during the joint session; a roll-call vote on the Valley Water Board showed directors voting in the affirmative.

What’s next: staff requested continued direction and support to develop a project charter and an exclusive negotiation agreement for land, continued coordination on public education and outreach, and semiannual updates to Valley Water advisory committees and governing bodies. The agencies said the exclusive negotiation agreement will be time limited and would not transfer land ownership but would provide Valley Water assurance that the identified land would not be offered for other uses during the negotiation period; staff said they expect to bring that agreement to advisory committees, the full Valley Water Board and the San Jose City Council in the coming months.

The joint meeting packet and staff presentations contain additional technical details and the draft feasibility study scope; staff said they will provide further briefings and bring specific agreements back to each governing body for formal action as those documents are ready.