AHSAHKA, Idaho – In order to meet flood control targets for March and April, Dworshak Dam will be decreasing releases starting Friday night, March 5, at midnight. This decrease will result in the river lowering less than 1 foot over the hour between midnight on Friday and 1 a.m. Saturday morning.
The rate of change in downstream river stage will be limited to below one foot per hour as measured at the United States Geologic Survey (USGS) Clearwater River Near Peck, ID (gage #13341050).
The basin’s snowpack remains above average, particularly at the lower elevations. Forecasts project slightly above normal temperatures and below normal precipitation for this time of year over the next week. This forecast, in combination with current basin conditions, has prompted the slight decrease in releases from Dworshak Dam and Reservoir near Orofino, Idaho. The release will be decreased from 15,000 cubic feet per second (cfs) and held constant at 13,800 cfs through Friday, March 12. Roughly 10,500 cfs will be released through the powerhouse at its maximum capacity, and the remainder will be released through the spillway.
The Corps works with regional water managers, other agencies, tribes, and fish managers and hatcheries in joint efforts to keep total dissolved gas (TDG) below the Idaho State maximum threshold of 110%, when possible. Spill from Dworshak is expected to cause the TDG below the dam to be approximately 110%. This planned operation is intended to provide flexibility in reducing the risk of TDG rising above 110% at the end of March and beginning of April when hatchery releases are scheduled. The forecasted runoff for the North Fork of the Clearwater basin will be continuously revaluated for the opportunity to reduce TDG while still meeting flood control targets for both March and April.
For safety, the public is advised to be aware of the danger associated with fluctuating river flows and elevations. The river at this time of year is deep, cold and fast, so extreme caution should be used near riverbanks. Boaters, anglers and other people using waterways both in Dworshak Reservoir and below the dam on the Clearwater River are advised to be alert to changes in water elevation and volume of flow. Current Dworshak water-management conditions can be viewed on the Walla Walla District website at https://www.nwd.usace.army.mil/CRWM/Water-Control-Data/Project-Data/.
Release no. 21-008