Four environmental groups have filed a U.S. District Court suit against the administration of the federal government's large dams in the West, saying Glen Canyon Dam, Flaming Gorge Dam and others damage the environment.

The suit was filed just as one important federal suit against the Western Area Power Administration, filed in October 1986 by Salt Lake City and 143 cities over the power administration's marketing practices, was being settled. All claims in the suit except environmental ones have been dismissed. Negotiations were apparently nearing a conclusion on the remaining claims, as a hearing was scheduled before U.S. District Judge J. Thomas Greene on Thursday.The latest action was filed in Salt Lake City against the power administration and the Department of Energy by the National Wildlife Federation, Grand Canyon Trust, America Rivers Inc. and Western River Guide Association.

Changes in marketing criteria for sale of power to customers in Utah, Wyoming, Colorado, New Mexico and Arizona will increase the dams' generation, the suit contends.

"Changes in CRSP (Colorado River Storage Project) dam operations that will result from implementation of the criteria could significantly affect the quality of the downstream environment, including fish, vegetation, beaches, recreation, wild fowl and riparian and riverine habitat," the suit says.

Implementation of the criteria has been hung up by the Salt Lake suit, it adds. But that suit is apparently nearing its conclusion.

The environmentalists contend the government failed to evaluate the option of maintaining stream flows to protect wildlife habitat and the environment. The government's environmental assessment rejected as "not viable" the alternatives for power sales that would reduce fluctuations and daily and hourly flows from the dams.

"Instead, WAPA developed plans to supply power for peak demand periods, resulting in periodic releases of large volumes of water downstream, and wide fluctuations in flow," the suit says.

A press release by S. Elizabeth Birnbaum of the National Wildlife Federation says, "These fluctuations are washing away beaches and streamside vegetation in the Grand Canyon and are pushing several species of native fish to the verge of extinction.

"Water levels on the Colorado (River) below the Glen Canyon Dam fluctuate as much as 13 feet each day."

A five-year study by the federal government concluded that fluctuations in water released from Glen Canyon Dam permanently damaged Grand Canyon National Park downstream along the Colorado River and that the damage is continuing. Flood releases rip out beaches and riverside plants, and the sand isn't replaced because silt backs up behind the dam.