The Nez Perce Tribe and two conservation groups reached a settlement agreement with the state of Oregon that they say will improve water quality at and below the three-dam Hells Canyon Complex on the Snake River and possibly lead to sockeye recovery in Wallowa Lake.

The tribe and the conservation groups — Pacific Rivers and Idaho Rivers United — sued the Oregon Department of Environmental Quality in 2019, arguing the state violated the federal Clean Water Act when it certified the proposed relicensing of Idaho Power’s dams at the southern end of North America’s deepest river gorge.