PORTLAND - Operators of the Columbia Basin hydroelectric dams told a federal judge Wednesday they do not expect to make the kinds of major changes in their strategy to boost salmon returns that are being sought by the state of Oregon and some Indian tribes.

Robert Gulley, the U.S. Justice Department attorney representing the federal agencies that operate and sell the power produced by eight federally owned hydroelectric dams on the Columbia and Snake rivers, said in U.S. District Court they will continue to collaborate with Indian tribes and states, but characterized the changes to be made in coming months as “refinements.”

U.S. District Judge James Redden has rejected the federal government's last two attempts to produce a plan for operating the dams that meets Endangered Species Act requirements for protecting 13 species of salmon and steelhead, known as a biological opinion, or bi-op for short.

Lawyers for the state of Oregon and Indian tribes with treaty fishing rights in the Columbia said the plan needs to be more aggressive on using the proven method of spilling water over the dams to increase juvenile salmon survival and guaranteed river flows during low water years.

At a status hearing, Redden stopped short of telling the federal agencies what to do, but said they must use the best science and work with the states and Indian tribes involved in a formal collaboration process he set up.

“I expect to have a bi-op that is acceptable or very close to it,” he said from the bench. “The consequences are going to be very serious.

“This is a very very very important document you are working on. I don't want to rush you. I want it to be right. We haven't done it right yet.”

Redden ruled two years ago that the Bush administration's 2004 plan for making the hydroelectric dams on the Snake and Columbia safe for salmon violated the Endangered Species Act. His ruling was upheld this year by the 9th U.S. Circuit Court of Appeals.

The ruling left open the possibility that four dams on the lower Snake River in Washington may have to be breached to help salmon. That option has been pressed by conservation groups and some Indian tribes.

The Bonneville Power Administration, which sells the power produced by the dams, and the U.S. Army Corps of Engineers and the U.S. Bureau of Reclamation, which operate the dams, came out with a new plan in May that offered few changes in the amount of water spilled over the dams to help juvenile fish migrating downstream or river flows - a strategy pushed by the state of Oregon.

BPA has spent $1 billion on salmon since 1995, and plans to spend $500 million more by 2010.

The new plan relies heavily of more devices known as removable spillway weirs that help young salmon swim safely over dams, increased control of predators, improved operations at fish hatcheries and more improvements to fish habitat.

“Just because we are not increasing spill and flow does not mean the bi-op fails,” Gulley said.

Attorney David Leith said the state of Oregon was “dismayed” the plan was not aggressive in the use of water spilled over the dams to help young juvenile salmon migrating to the ocean and relied so heavily on the removable spillway weirs, which are unproven.

David Cummings, attorney for the Nez Perce Tribe, said they were frustrated that their suggestions were not being adopted, and would like to see a backup plan that allowed for the breaching of four Snake River dams.

After the hearing, Todd True, an Earth justice attorney representing the conservation groups that brought the lawsuit challenging the biological opinion, said the federal agencies appeared to be following the same path as in 2004, when they produced the biological opinion that Redden found violated the Endangered Species Act.

“There are quite a few parties who think that's not going to comply with the law.” he said after the hearing.