Stoneridge PFAS Treatment Plant

In a continuing effort to supply the Tri-Valley with safe, reliable water that surpasses state and federal drinking water standards, Zone 7 constructed a water treatment system to address Per- and Polyfluoroalkyl substances (PFAS) found in the local groundwater at the Stoneridge Well. The treatment system went online in September 2023.

ABOUT THE PROJECT

• The purpose of the project is to add necessary water treatment facilities to the existing Stoneridge Well to remove PFAS from the well’s groundwater supply.
  • Installation of Ion Exchange (IX) treatment system for PFAS removal
  • Rerouting of existing site piping, additional new site piping and appurtenances, and new booster pump
  • Chemical systems modifications, new electrical equipment and building, and new instrumentation and controls
• The cost for the project was $16.3 million for planning, design, and construction
  • The Department of Water Resources (DWR) awarded Zone 7 a $16 million grant through the Sustainable Groundwater Management (SGM) Grant Program.
• The treatment plant is at Zone 7’s Stoneridge Well, located at 3750 Stoneridge Drive in Pleasanton.
• Download our general one-sheet to get an overview of the new facility. Stoneridge Well General One-Sheet
• Download our technical one-sheet for detailed information on the technology. Stoneridge Well Technical One-Sheet

Ion Exchange Treatment

How Ion Exchange Treatment works at Stoneridge to remove PFAS

CONSTRUCTION SCHEDULE & UPDATES

• At the regularly scheduled Board meeting at 7:00 p.m. on October 19, 2022, the Board approved the project.
• Construction for the project began on February 2, 2023.
• The treatment system went online in September 2023.
  • Read the news release: Zone 7 Water Agency celebrates the grand opening of its Ion Exchange (IX) PFAS Treatment Facility at Stoneridge Well.
  • See the new treatment facility featured on TV 30’s Slice of Life.

CONTACT OUR PROJECT TEAM

Please contact Brandon Woods at (925) 454-5078 or bwoods@zone7water.com with any questions. 

Learn more about PFAS

• All water supplied to our customers meets the regulatory standards set by the state and federal governments. 
• In almost all cases, the quality was significantly better than required. 
• Zone 7 continues to deliver all water below the California Division of Drinking Water’s response levels for PFOA and PFOS.
• For more information about how we keep your water safe from PFAS click here.
• To learn about new PFHxS advisory levels click here.