BOISE, ID (AP)
Three environmental groups and two commercial fishing advocacy groups say they will file a lawsuit against the federal government over heat-related fish kills in the Columbia River Basin in the Pacific Northwest.
The groups on Monday sent a 60-day notice of their intent to sue the U.S. Environmental Protection Agency for what the groups say are violations of the Clean Water Act.
The groups say 250,000 adult sockeye salmon died in 2015 due to high temperatures in the Columbia River and lower Snake River.
Idaho Rivers United, the Pacific Coast Federation of Fishermen's Associations and the other groups say a die-off could happen again.
The groups say the federal agency has failed to create a plan to control water temperatures.
Last year management teams released cold water from selected reservoirs in an attempt to lower temperatures below 70 degrees to prevent similar fish kills among chinook salmon and steelhead, which migrate later in the summer from the Pacific Ocean.
The fish become stressed at temperatures above 68 degrees and stop migrating at 74 degrees.
Much of the basin was at or over 70 degrees because of a combination that experts attributed to drought and record heat in June.
Of the 4,000 fish that passed Bonneville Dam on the Columbia River, less than a fourth made it to Ice Harbor Dam on the Snake River. An average year is 70 percent.
"Right now it's grim for adult sockeye," said Russ Kiefer of the Idaho Department of Fish and Game.
He said sockeye will often pull into tributary rivers in search of cooler water, but didn't find much relief.
"They ran out of energy reserves, and we got a lot of reports of fish dead and dying," he said.
Thirteen species of salmon and steelhead are listed as endangered or threatened in the Columbia River basin.