One Water Plan

One of the City Council’s priorities for 2022 is Climate Action-Protection and Adaptation. A City effort underway is developing the “One Water Plan”, a key action within the City’s Sustainability and Climate Action plan (S/CAP). The development of a water plan will evaluate alternative water supplies, define existing and future uncertainties and supply risks, and identify community needs and priorities. The Plan will serve as a long-term guide to better prepare for future uncertainties like multi-year drought, climate change, and more.


Palo Alto’s Water Supply and Conservation

The City of Palo Alto receives 100% of its potable water from the San Francisco Public Utilities Commission (SFPUC) through the Regional Water System (RWS). The City also uses some recycled water produced at the Palo Alto-operated Regional Water Quality Control Plant (RWQCP) for irrigation of the municipal golf course, a park, and some other minor applications. A system of local groundwater wells and storage provide emergency water supply service. The City currently partners with Valley Water to offer a wide range of water conservation programs to the community. 

Water Supply Reliability

Since the City relies on the SFPUC’s Regional Water System (RWS) for its potable water supplies, the City’s current water supply reliability mirrors that of the RWS. Palo Alto needs to carefully consider the vulnerabilities and resilience of the RWS in its own water supply planning efforts. The One Water Plan will consider uncertainties, such as the outcome of the Water Quality Control Plan for the San Francisco Bay/Sacramento-San Joaquin Delta Estuary (Bay Delta Plan Amendment or Bay Delta Plan). 


  • Develop evaluation criteria for Assessing Water Supply and Conservation Portfolio Alternatives  
  • Develop and Evaluate Future Water Supply and Conservation Portfolio Alternatives  
  • Engage Stakeholders 
  • Final Report and Excel-based tool for evaluating and prioritizing the water supply and conservation alternatives


  • Scope Discussion: Utilities Advisory Commission July 2021 (Staff Report #12332)  
  • One Water RFP Issued: Palo Alto Utilities Department in collaboration with the Public Works Department issued RFP November 2021  
  • One Water Contract with Carollo Engineers approved by Palo Alto’s City Council June 2022 (Staff Report #13434)  
  • First Community Workshop, September 28, 2022 -View the presentation and results from the live polling(PDF, 16MB).
  • Second Community Workshop, December 6, 2022 - View the slides(PDF, 14MB) and recording.
  • Planned Third Community Workshop: Sharing the Initial Results in summer 2023
  • One Water Plan expected to be completed by the end of 2023   

One Water Plan – Existing Plans, and Effluent Transfer Agreement

The One Water Plan will leverage existing completed and in-progress plans to evaluate alternative water supplies with the potential to make Palo Alto’s water supply more resilient. These plans include: 

  • Northwest County Recycled Water Strategic Plan, completed by Palo Alto together with Valley Water and the City of Mountain View, sought to identify the most appropriate ways to expand the City of Palo Alto’s Recycled Water Program. The Northwest County Recycled Water Strategic Plan was accepted by Palo Alto City Council in 2020 (Council Report #10913). Visit the Recycled Water Pipeline & Strategic Plan Website.
  • A detailed Groundwater Assessment, completed as part of the Northwest County Recycled Water Strategic Planning efforts, characterized the hydrogeologic conditions in Palo Alto and surrounding areas as well as evaluated the feasibility of increased groundwater pumping by Palo Alto and refined the estimate of groundwater yield available to Palo Alto.
  • Green Stormwater Infrastructure (GSI) Plan describes how the City will gradually integrate GSI features into its urban landscape and storm drain system over several decades. While the primary purpose of GSI is stormwater pollution control, GSI also represents a water supply option. The One Water Plan will consider this possibility. 
  • In 2019 Council approved an Effluent Transfer Agreement with Valley Water and the City of Mountain View (Council Report #10627). This 76-year agreement enables an effluent transfer from the Regional Water Quality Control Plant to Valley Water to be reused in Santa Clara County, likely south of Mountain View. A Council study session with Valley Water on September 12, 2022 provides updated information (Council Report #14650).
  • Palo Alto’s 2020 Urban Water Management Plan & Water Shortage Contingency Plan includes an assessment of the reliability of Palo Alto’s water sources, an analysis of water demand, a description of water conservation efforts, and a water shortage contingency plan.