The cost to pump water over vast distances is enormous. For example, California’s State Water Project relies on a series of pump stations to carry water from the Sacramento-San Joaquin Delta to the southern part of the state. The most powerful, Edmonston Plant, requires 14 gigantic pumps with a combined draw of over 7,460 megawatts to lift the water 587 meters uphill to a series of tunnels over the Tehachapi Mountains. The state’s other major source of water, the 389.5-kilometer-long Colorado River Aqueduct, also draws an enormous amount of electricity. Imported river water requires approximately 14,000 kilowatt-hours per million gallons, 1,000 less than a comparable volume of desalinized water.

The State is planning to build as many as 17 desalination plants. Claude Lewis Carlsbad Desalination Plant has been in operation in San Diego County since late 2015. It is the largest in the Western Hemisphere, producing 50 million gallons of water a day. Another in Huntington Beach of similar capacity is in late-stage development. Together these plants are going to draw an estimated 1,500,000 kilowatt-hours, or 1,500 megawatt-hours. Accordingly, if and when the State builds all the plants, their combined draw will be 12,750 megawatt-hours.