The state of Montana has joined a lawsuit contesting Libby Dam operations - but not necessarily with the same views as the lead plaintiff.

The state last week intervened as a plaintiff in a lawsuit initiated by the Center for Biological Diversity, which has staunchly advocated higher flows in the Kootenai River to benefit white sturgeon, an endangered species. The environmental organization wants higher flows, even if they may involve releasing water over the dam's spillways.

The state opposes the spilling and joined the lawsuit largely because of a 20-day, unplanned spill operation last month, said Bruce Measure, one of Montana's two representatives on the Northwest Power and Conservation Council.

"That's the area where we differ from them," Measure said of the Center for Biological Diversity. "But we do not differ from them in wanting to recover the fish."

The U.S. Fish and Wildlife Service, the defendant in the case, recently issued a biological opinion for Libby Dam operations that puts an emphasis on spilling to improve sturgeon spawning success in the Kootenai River.

But that position conflicts with Montana water-quality standards that limit dissolved gas levels that are caused by releasing water over the spillways. Spill is an issue for the state largely because of the harm excessive gas levels cause fish populations below the dam.

"Montana chose to litigate only after exhaustive consultations with the USFWS and other federal agencies to promote a recovery strategy based on regional consensus rather than the hastily prepared biological opinion … containing spill and other proposals opposed by most other fish and wildlife managers on the Kootenai," Measure said.

Last month's spill came about after flows into the reservoir raised Lake Koocanusa to a point where water had to be released over the spillways, in addition to operating the dam at maximum powerhouse capacity.

Biologists monitoring fish downstream found increasing symptoms of "gas bubble trauma" as the spill continued.

The spill "caused significant downstream property damage as well as skin ruptures and other symptoms of gas bubble trauma in virtually all of the cutthroat and bull trout downstream of Libby Dam as the state had earlier predicted," Measure said.

"Montana will do all it can to protect our fish and our people above and below Libby Dam," added Rhonda Whiting, Montana's other representative on the Northwest Power and Conservation Council. "The lawsuit will be another venue for us to further promote stable summer operations, and reasonable operations year round, for that matter, at Libby that we have been fighting to get implemented since Gov. Schweitzer came into office."

Measure said Montana intervened in the case to present U.S. District Judge Donald Molloy of Missoula with a "third party view for what a reasonable operation for Libby Dam would be," Measure said.

The court is likely to hear from other interested parties, Measure predicted. The Kootenay Tribe of Idaho also plans to intervene in the case - joining as a defendant with views similar to Montana's, Measure said.

"There are a lot of folks who are interested in these river operations and preventing the type of operation we had this year," he said.

Reporter Jim Mann may be reached at 758-4407 or by e-mail at jmann@dailyinterlake.com