SAN DIEGO -- San Diego County Water Authority officials say it could be a very long time before they identify any new seawater desalination projects to chase seriously after abandoning long-discussed hopes of helping build a Carlsbad plant that would turn ocean water into drinking water.

Water Authority officials said it would be "at least a year to a year-and-a-half -- and possibly much longer -- before potential seawater desalination projects in South County and the San Onofre Nuclear Generating Station could be considered serious and plausible.

Meanwhile, questions remain about how supportive the regional Water Authority will be when asked to support the continuing efforts to build by the long-discussed Carlsbad plant, even though the Water Authority considers it "critical" to the region's future water supply.

The city of Carlsbad and Poseidon Resources Inc. -- the private company that the Water Authority could not successfully negotiate its own deal with to build the plant -- are continuing to advance their own plans to build the facility.

Water Authority board members publicly promised to support Carlsbad's continuing efforts.

But board members have already questioned if the Water Authority would pass on to Carlsbad and Poseidon a financial subsidy that most consider a key to making the project work.

And Water Authority officials last week refused to say if they would testify before the California Coastal Commission -- the regulatory agency that must approve the project -- to support the plan.

"I think that's premature to say that," Water Authority Assistant General Manager Dennis Cushman said.

The Water Authority had been trying to cut a deal with Poseidon since 2001 to try to build the proposed Carlsbad plant, saying desalination would provide the county's first "drought-proof" water supply.

But the agency's board pulled the plug on the its involvement at its July 28 meeting for two reasons.

First, the board said it no longer believed it could reach any sort of deal with Poseidon -- the company that has been studying the idea of building a desalination plant at Encina since 2000, and which has a 60-year lease on the property.

Second, the board said they were completely unnerved by recently-announced changes intended for the Encina plant site.

Three weeks ago, the company that owns the power plant, NRG Energy, Inc., said it intended to build a new power plant at the Encina site, and to shut down, demolish and sell off portions of the current site.

Now what?

When Water Authority board members voted to end their pursuit of the proposed Carlsbad plant, they said they still hoped the city of Carlsbad and Poseidon could build it.

And they directed their staff to look elsewhere -- to come back in August with ideas for where the Water Authority might still pursue its dream of seawater desalination.

The agency has already looked at the possibility of building seawater desalination plants somewhere in South County, or at the San Onofre Nuclear Generating Station.

But Ken Weinberg, the Water Authority's water resources manager, said last week that those studies were in their earliest stages.

He said even identifying those possibilities as serious enough for environmental study was at least a year to 1 1/2 years away.

Challenges increasing?

At the same time, Weinberg sounded as if the potential obstacles facing seawater desalination seemed to be increasing in number.

Water officials thought electrical power plants like Encina would make perfect homes for seawater desalination projects because they already had the two essential things a desalination plant would need -- seawater sucked into plants to cool electrical turbines, and the power to fuel pumps and filters.

But Weinberg said environmental groups are mounting increasing challenges to the "once-through-cooling" systems that use seawater to cool their engines, saying they harm marine life.

Weinberg, Cushman and others said the Water Authority wasn't throwing in the towel on the idea of seawater desalination.

"The Water Authority is not backing away from seawater desalination," Cushman said. "It's still a critical piece of our supply portfolio."

Water Authority board member Bud Pocklington, who was part of the long negotiations with Poseidon, said seawater desalination is essential because the West's population -- and the world's population -- is growing faster than its finite water supplies.

"To solve the world's problems, seawater desalination has to be an answer," Pocklington said.

How committed?

Even so -- and despite Water Authority board members' statements that they hope Carlsbad and Poseidon succeed -- there seem to be questions about just how supportive the Water Authority will be.

Poseidon negotiated with the Water Authority for nearly five years to build the proposed $270 million Carlsbad plant -- realizing that the Water Authority represented a lot of money, and the combined water-demand that could ensure the project's success.

But it also tried to cobble out a local deal with the city of Carlsbad and a handful of the Water Authority's other member agencies -- such as the Valley Center Municipal Water District -- the deal the company will continue to move forward.

But even that deal was heavily reliant upon the Water Authority, because of a $250 per-acre-foot subsidy that the Water Authority hoped to get from the Metropolitan Water District of Southern California. The subsidy would cut the cost of the water the Carlsbad plant would produce from $800 per acre-foot to $550 per acre-foot -- enough to make it competitive with the roughly $450 per acre-foot cost of regular, imported water. An acre-foot is enough water to sustain two households for a year.

The Water Authority had promised to pass that subsidy along to Carlsbad. But Metropolitan board members this spring passed a resolution saying any of its member agencies that wanted the subsidy had to promise not to sue Metropolitan over other issues -- such as the cost of water.

Water Authority leaders would not commit to making that promise and giving that subsidy to Carlsbad at their July 28 meeting.

That could have a trickle-down effect. Valley Center and other officials said they wouldn't buy Poseidon's water without the subsidy. And that could mean that Poseidon would suddenly be faced with the prospect of building a desalination plant, and only being able to sell less than half of the water it produced.

Poseidon Vice President Peter MacLaggan said Friday that even though the Water Authority broke off talks with the company, Poseidon was still very confident that it could make the proposed Carlsbad plant a reality.

Pocklington, meanwhile, said the Water Authority may now be faced with taking a step backward in its own quest to make seawater desalination a reality.

He said the Water Authority's only real choice may be to try to push Metropolitan -- Southern California's regional water supplier -- into trying to create its own desalination projects throughout the region.

Contact staff writer Gig Conaughton at (760) 739-6696 or gconaughton@nctimes.com.