CARLSBAD ---- More than five years after it began, the city's review of environmental documents for a proposed seaside desalination facility is expected to end Tuesday.

During its 6 p.m. meeting that day, the Carlsbad City Council will be asked to certify the project's environmental impact report and approve various permit documents.
Carlsbad's leaders have long backed the concept, saying it would provide the city with a guaranteed local source of drinking water instead of relying on imported Colorado River water. The proposal cruised through its May 4 Planning Commission hearing, with one commissioner calling it "the most significant" one he would ever handle as commissioner.

But the project, which would produce up to 50 million gallons of drinking water a day, has faced opposition from coastal environmental organizations, including the Surfrider Foundation, who say it will have harmful effects on the area's marine environment and promotes wasteful water use.

These concerns won't have their final airing at Tuesday's meeting because the city of Carlsbad doesn't have the final say on whether developer Poseidon Resources Corp. can put its nearly $300 million desalination plant on the land within the Encina Power Station on Carlsbad Boulevard.

That decision is ultimately up to the state Coastal Commission, which has already indicated it too has some environmental concerns about the project. And, there's another complicating factor ---- this isn't the only desalination plant proposed for the site.

As Carlsbad's council debates this version of the project, the region's main water provider ---- the San Diego County Water Authority ---- is finishing work on its own environmental document for a separate proposal.

"We are trying to go to our board at their June 22 meeting," said Ken Weinberg, the agency's director of water resources.

Under the authority's proposal, Poseidon would build the plant, but the water agency would own it and it would be a regional water production facility. In contrast, the concept that Carlsbad's council will debate Tuesday calls for a privately owned plant that would sell its water to individual communities.

Carlsbad officials have said they like the idea of a regional plant better than the one they're considering next week, however, the Water Authority and Poseidon haven't reached agreement on the details of that project despite years of negotiations.

While those talks with the water agency continue, Poseidon is pushing forward with the private plant proposal. Company Vice President Peter MacLaggan said Friday that if Carlsbad's council votes in favor of it at Tuesday's meeting, his company will submit its plans to the state Coastal Commission within the next month for its review.

Those plans will have some company when they arrive. A similar project Poseidon is planning for Huntington Beach is already before the state commission.

-- Contact staff writer Barbara Henry at (760) 901-4072 or bhenry@nctimes.com.