Del Valle Water Treatment Plant
The Del Valle Water Treatment Plant has been serving the Tri-Valley community since the 1970s and was recently upgraded to add raw water ozonation to the existing treatment process. The ozonation project is the latest investment by Zone 7 to support the continued delivery of high-quality water to Zone 7 customers.
Patterson Pass Water Treatment Plant
The Patterson Pass Water Treatment Plant has been serving the Tri-Valley since 1962, treating imported surface water from the adjacent South Bay Aqueduct using dual-media filtration and chlorine treatment techniques. The plant has recently been upgraded to add ozone treatment. The plant capacity has also been expanded from 12 million gallons per day (mgd) to 24 mgd.
- Patterson Pass Water Treatment Plant Upgrades and Ozonation Project Brochure
- 2/6/2019 PPWTP Upgrades and Ozonation Project Board Presentation
- Patterson Pass Water Treatment Plant Upgrades and Ozonation Project: 2/16/22 Construction Progress Report
- Patterson Pass Water Treatment Plant One-Sheet
- Read more
Water Quality Lab at Del Valle Water Treatment Plant
Our state-of-the-art water quality lab is housed at the Del Valle Water Treatment Plant and run by expert water quality chemists and technicians willing to carry the weight of the world on their shoulders – or at least the weight of Tri-Valley’s water.
Mocho Groundwater Demineralization Plant
The Mocho Groundwater Demineralization Plant began operating in August 2009 and is a very different kind of treatment plant than the Del Valle and Patterson Pass plants, which both treat imported surface water.
Stoneridge Well PFAS Treatment System Project
In a continuing effort to supply the Tri-Valley with safe, reliable water that surpasses state and federal drinking water standards, Zone 7 is in the final stages of constructing 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 and final construction at the facility is anticipated to be complete by Spring 2024.