The authority's board approved a 30-year purchase agreement Thursday with Poseidon Resources, the developer of the plant located in Carlsbad, 35 miles north of San Diego.
Poseidon still has to obtain financing for the project, which with a capacity to produce enough fresh water for 112,000 homes would be the largest seawater desalination facility in the country, the Los Angeles Times reported.
The San Diego Water Authority long attempted to lessen its dependence on supplies imported from the Metropolitan Water District of Southern California.
That independence will come at a price; when the cost of necessary new distribution pipelines is included, the desalinated water will cost $2,041 to $2,290 an acre foot, more than double the cost of water from Metropolitan, the Times said.
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