Only 10 years ago, the idea that Californians might one day drink treated wastewater from their kitchen taps seemed unfathomable. The notion of using recycled water to this degree was unpopular with the public, and seemed unnecessary.

The state’s ongoing drought has changed all that. Many water agencies over the past few years have rolled out small recycled water programs. These are mainly producing nonpotable water for outdoor irrigation, and have become popular with people who want to continue watering their gardens without impacting their water bills.