The city of San Diego pursued its massive wastewater-to-drinking water recycling program, in part, because the federal government said it had to. Millions of gallons of undertreated sewage enters the Pacific Ocean through the city’s aging Point Loma treatment plant on the regular; Pure Water is the region’s first step toward a solution.

But now, a bloc of eastern San Diego County water agencies is building their own recycling project because, they say, the cost of buying imported water from the drought-ravaged Colorado River is unsustainable.