Corps Investigates Steelhead Mortalities at Dworshak Dam
US Army Corps of Engineers
OROFINO – In late December 2021, Idaho Department of Fish and Game notified U.S. Army Corps of Engineers Walla Walla District officials of reports of numerous dead steelhead downstream of Dworshak Dam. Upon their investigation it was confirmed that approximately 30 deceased adult steelhead trout were visible in Dworkshak’s downstream channel.
This event coincided with start-up procedures for a turbine at Dworshak Dam. A preliminary internal review has concluded that all required and set procedures for turbine start-up were followed. These procedures, which include using compressed air to lower the water level below the spinning turbine blades, are designed to greatly reduce incidences of fish mortality, though, they do not eliminate all risk.
Currently, the Walla Walla District is gathering more information about this incident and will release any findings of significant interest as they become available. The Walla Walla District thanks the public for their understanding and patience during this period and appreciates the assistance of our partner agencies.