Oct 13 (Reuters) - A $140 million desalination plant is expected to be approved by California regulators on Thursday as the U.S. state contends with how to convert ocean water into drinking water amid the worst drought in 1,200 years. Instead of relying on water pumped from hundreds of miles (km) away, through the State Water Project or the Colorado River, the South Coast Water District would now have its own water supply. The Doheny plant would produce 5 million gallons of drinking water per day, more than enough to meet the needs of the district's 35,000 people. The Coastal Commission staff, which recommended rejecting Poseidon, favors building Doheny, which would be the 12th desalination plant approved by the regulator. The Doheny plant will use a sub-surface intake that creates a barely perceptible current.

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