Earlier this month, the California Coastal Commission approved plans for a desalination plant near Doheny State Beach. In May, the commission voted against a plant in Huntington Beach. Today we look at the differences.

The greenlighted $140 million desalination plant in south Orange County’s city of Dana Point includes technology preferred by environmentalists and regulators and could provide up to 5 million gallons per day. Unlike the rejected $1.4 billion plant in Huntington Beach, the Doheny Ocean Desalination project location has unique hydrogeology that allows advanced slant wells (shown in graphics on the right) to draw water from beneath the ocean floor to protect marine life.

The plant will help serve the South Coast Water District’s roughly 35,000 residents in Dana Point, South Laguna Beach and parts of San Clemente and San Juan Capistrano. Water rates for residents may increase $2-$7 per month.

The other major difference between the Doheny plant and the site in Huntington Beach is how the brine from the ocean’s saltwater will be released. Brine left over by the desalination process can kill marine life when released back into the ocean. But the Doheny plant is sending the discharge to a nearby wastewater treatment plant, where the salty discharge would be diluted with ocean water and sent through an existing pipeline that goes out to sea.