California approves desalination plant as drought hits water supplies

California regulators this week approved a $140 million desalination plant that could convert up to 5 million gallons of seawater each day into drinking water, as the state grapples with a persistent megadrought and plummeting water supplies.

The state’s Coastal Commission on Thursday voted 11-0 to approve the Doheny Ocean Desalination Project in Orange County in Southern California. The plant could be functioning within the next five years and supply water for thousands of people in the South Coast Water District.

The approval comes as record temperatures and drought conditions have forced states like California to address a future with dwindling water supplies.

The megadrought gripping the Western U.S. has generated the driest two decades in the region in at least 1,200 years, and scientists say that human-caused climate change has fueled the conditions. Water levels at the two largest reservoirs in the country, Lake Mead and Lake Powell, have hit their lowest levels ever recorded.

In August, California Gov. Gavin Newsom unveiled a plan to address an anticipated loss of 10% of the state’s water supply by 2040. California officials earlier this year warned the state could face its third consecutive dry year because of a significant lack of snow this season. And water officials slashed State Water Project allocations from 15% to 5% for urban water consumers and farmers.

State regulators in May unanimously rejected a much larger $1.4 billion desalination plant in Huntington Beach, citing the costs of the water, potential risks to marine life and hazards associated with sea level rise and flooding.

However, officials have argued that the smaller Doheny plant will have an environmental design that better addresses potential damage to marine life. 

There are 12 existing desalination facilities throughout California, according to the state’s Water Resources Control Board, including the Carlsbad desalination project in San Diego County, which is the largest desalination plant in the western hemisphere and produces three million gallons of drinking water each day.