Desal plant gets green light

The site of a proposed Carlsbad desalination plant

A project that would be the West Coast’s first large-scale desalination plant received final approval from regulators in May after a six-year permitting battle.

The proposed plant, called the Carlsbad Desalination Project, is expected to produce 50 million gallons of water per day for use in San Diego County.

The approval will likely set a precedent for other desalination projects in California, as water agencies look to compensate for a reduction in water supplies from other sources, says Scott Maloni, a spokesman for Poseidon Resources, the project’s developer.

However, the location of the Carlsbad plant is key to its viability, according to Maloni. Located next to a power plant that uses seawater for cooling, the desalination facility is designed to filter the cooling water through reverse osmosis, and mingle its salty byproduct with the power plant’s discharge. Maloni estimates that there are currently about 25 such seawater-cooled power plants in California. Poseidon is in the permitting process for another desalination facility next to one such power plant in Huntington Beach, Calif.

Stamford, Conn.-based Poseidon doesn’t yet have the funding in place for the $300 million project, but says it plans to begin securing private financing this year with the goal of beginning construction by late 2009 and completion expected by 2012.

Environmental groups contested the project throughout its approval process, expressing concern about harmful impacts to the surrounding ecosystem. Poseidon plans to create 55 acres of wetland habitat to compensate for harm done to wildlife.

Desalinating that much water will require huge amounts of electricity, more even than importing the water from other regions, Maloni says. Poseidon plans invest $55 million in a climate action plan to offset its indirect emissions.