More severe droughts are looming. Could Santa Rosa’s pioneering water recycling program help stave off disaster?


Homes and businesses across central Sonoma County generated more than 5 billion gallons of wastewater last year, enough to fill more than 7,500 Olympic-sized swimming pools. That sewage flowed into Santa Rosa’s regional treatment plant south of Sebastopol, where it was cleaned up and nearly all of it put to a second use.

About 4 billion gallons of recycled water was pumped north from the Llano Road treatment plant in a 41-mile pipeline and up a steep slope into The Geysers geothermal fields southeast of Cloverdale. There it was injected into the ground to generate enough clean, renewable energy for about 100,000 North Bay households.

The system also sent 788 million gallons of recycled water to 61 farms covering 6,400 acres that produce milk, hay, grapes and vegetables, along with 386 million gallons for urban irrigation in Rohnert Park and Santa Rosa, the two largest cities in the wastewater system.

Every drop of the recycled irrigation water — safe for everything short of human consumption and sanitized to a degree that eliminates the COVID virus — replaces a drop of potable water from sources sure to be strained as California moves into its third year of worrisome drought.