From Toilet to Faucet

Orange County, CA's new $480 million Groundwater Replenishment System is the world’s largest water recycling facility of its kind. It can turn wastewater and into drinking water, churning out up to 70 million gallons a day.

1 minute read

August 1, 2008, 5:00 AM PDT

By Tim Halbur


"(The s)ystem takes already-treated wastewater from the sanitation district next door and sends it through a rigorous three-step cleaning process. It's washed through microfiltration, pressed through rows of reverse osmosis membranes, and then blasted with ultraviolet light and hydrogen peroxide. After 45 minutes, out comes clean, drinkable water.

The final product doesn't go directly to the tap. Instead, half of it flows into a seawater barrier and the other half into a freshwater pond that replenishes the county's groundwater basin. In the end, the recycled water makes up about 20 percent of the drinking water for roughly 2.3 million people.

It's not necessarily the technology that has garnered Orange County such attention from water utilities around the globe. Recycling wastewater has been going on to lesser degrees elsewhere for some time. What has intrigued many is that the system met almost no public resistance when it came online in January.

"Technologically, it's almost trivial for us to do this now. The key is to get public acceptance and political buy-in," says Dr. Cooper, an early pioneer in water reuse practices."

Wednesday, July 30, 2008 in The Christian Science Monitor

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