answer:Sure. My county does it all the time, hundreds of millions of gallons each day. Household water goes through the sanitary sewers and is pumped to one of three water treatment plants. There it is cleaned, filtered, chemically treated, and then pumped back into Lake Lanier (the lake which is our water supply). yesterday’s urine s tomorrow’s scotch-and-water. We have had treated and recycled water here for 20+ years. Don’t know why California took so long.