Located in Carlsbad, California, Claude “Bud” Lewis Carlsbad Desalination Plant is the largest seawater desalination plant in the nation. The plant delivers nearly 50 million gallons of fresh, desalinated water to San Diego County on a daily basis. 

A 30-year water purchase agreement is in place between the San Diego County Water Authority and Poseidon Water, a water project development specialist, for the entire output of the plant.

The plant has delivered water to San Diego County since December 2015 and normally operates with a staff of approximately 40 employees working full time. This has since changed after public health orders announced that no more than 10 people can congregate in one place.