Seattle, Wash.-- The U.S. Army Corps of Engineers is prepared to increase outflows from Chief Joseph Dam in the next several days due to warmer temperatures and melting snow pack above Grand Coulee Dam.  It is expected that Chief Joseph Dam will begin to spill Saturday.

       According to Carolyn Fitzgerald of the District Water Management Office in Seattle, Chief Joseph Dam is a “run of the river dam.” This means that inflow coming into the dam must be passes downstream. Once inflow exceeds the capacity of the powerhouse to generate electricity, the excess water must be passed through the dams spillway gates to maintain the desired pool level behind the dam, according to Fitzgerald. She notes that only a few of the spillway gates nearest the power house are likely to be needed for the spill and that down stream effects will be minimal.

         “It will come nowhere close to approaching the most recent flooding events in 1996 and 1997,” she asserted. However, she added that recreational river users downstream should be aware that the river conditions can change rapidly and that both velocity and depth of the river will be greater than normal. These conditions could easily result in disaster for small boat approaching too close to the dam or not being vigilant for changing conditions. 

          The Corps operates and maintains Chief Joseph Dam for multiple uses that are consistent with project authorizations and applicable laws and regulations. The Corps' primary consideration is minimizing risk to human life, health and safety while meeting Chief Joseph Dam's multiple purposes and responsibilities.