CARLSBAD, Calif. -- The San Diego Regional Water Quality Control Board approved the final permit for the proposed Carlsbad Desalination Plant, 10News' Joe Little reported.

Poseidon Resources, the plant's developer, said Wednesday's decision clears the path for construction to begin later this year. When completed, the plant will turn seawater into 50 million gallons of drinking water every day, or 10 percent of the supply for San Diego County.

The company said it hopes to complete the more than $300 million project, which will be located adjacent to the Encina Power Station at Agua Hedionda Lagoon, by 2012.

When it's finished, the desalination plant will be capable of converting enough ocean water into drinking water to meet the needs of 300,000 residents.

To mitigate any environmental impacts from the project, the water quality control board required Poseidon to create 55.4 acres of coastal wetland habitat in Southern California.

However, this may not be the last step for Poseidon. There are still two lawsuits filed on behalf of local environmental groups that could stop construction. The California Coastal Commission could also ask to review the permit it already issued Poseidon.

The environmental groups, Surfrider Foundation and Coastkeeper, oppose the plant because they say the desalination technology is harmful to the environment and kills too much marine life.

Surfrider has filed two lawsuits: one against the Water Control Board for approving the plant's permit, and the other against the State Lands Commission over the plant's lease. Those cases are scheduled for trial next month.

This latest hearing was the 14th during the past six years, totaling more than 70 hours of testimony. Barring any hiccups, Poseidon hopes to have the desalination plant producing water by 2012.