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What is purified water?

Water has always been nature’s renewable resource and is constantly moving through the water cycle. Purifying water simply speeds up that natural process by using a multistep effort to remove potential water contaminants, creating a drought-resilient and sustainable water source. Purified water first starts out as highly treated wastewater that has already gone through a multi-step treatment process at a wastewater facility. Once that highly treated wastewater arrives at our treatment facility, it goes through a multi-step purification process, which can include micro-filtration, reverse osmosis, and UV light disinfection and advanced oxidation. This purified water is treated to strict standards set by the Division of Drinking Water and is rigorously monitored by local, state and federal agencies to ensure it continuously meets those standards. All purified water in Santa Clara County meets or exceeds standards set by the state.

How Safe is Purified Water?

As mentioned, purified water is safe and meets or exceeds state and federal drinking water standards. It is tested regularly by our certified Water Quality Lab to ensure safety and quality. Upon completion of the Purified Water Project, Valley Water will be able to use purified water to add to our groundwater replenishment efforts. Valley Water will join many other places in the United States and worldwide in using this water purification and replenishment method, including Monterey and Orange counties in California, Texas, Australia and Singapore.

The Silicon Valley Advanced Water Purification Center (SVAWPC) and the Purified Water Project

To learn more about how purified water is used as a drinking water source and the purification treatment process, please visit There, you can also sign up for tours of the existing SVAWPC, which currently produces up to eight million gallons per day of highly purified water.

This highly purified water is blended into existing recycled water provided by SBWR, which improves overall recycled water quality so that the water can be used for a wider variety of irrigation and industrial purposes. In the future, Valley Water is planning to expand purified water use into groundwater replenishment, similar to the highly successful groundwater replenishment system that has been operated by the Orange County Water District for over 30 years.

For more information about this effort, please visit the Purified Water Project website.