EditorialJeremy Crutchfield of the San Diego County Water Authority, left, and Sachin Chawla, president of Poseidon Resources, near the reverse osmosis membranes at the Carlsbad Desalination Plant in Carlsbad, Calif. on Aug. 18, 2021. (Ariana Drehsler/The New York Times)
EditorialPart of the water-filtration system at Salesforce Tower in San Francisco, including a reverse osmosis skid, on July 30, 2021. (Jim Wilson/The New York Times)