The Detroit Dam in March 2017. The U.S. Army Corps of Engineers has proposed building a 300-foot tower at the dam to improve water temperature and fish passage for salmon and steelhead.

The Detroit Dam in March 2017. The U.S. Army Corps of Engineers has proposed building a 300-foot tower at the dam to improve water temperature and fish passage for salmon and steelhead.

Bradley W. Parks/OPB

Three environmental groups followed through on a threat to sue the federal government Tuesday over the decline in wild salmon and steelhead in the Upper Willamette watershed.

The groups say the U.S. Army Corps of Engineers and National Marine Fisheries Service have failed to take required steps to improve conditions for the threatened fish.

The lawsuit targets the Willamette watershed’s system of dams and its negative impact on fish habitat. 

“Federal dam operators in the Willamette River basin must act now to protect our native fish,” said Mark Sherwood, executive director of the Native Fish Society.

Read the full story at the Statesman Journal.

Watch: Can dams and salmon coexist?