Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed- Sediment Cores from the Lower Granite Reservoir and Snake and ... Eastern Washington and Northern Idaho, 2010

Lower Granite Dam impounds the Snake and Clearwater Rivers in eastern Washington and northern Idaho, forming Lower Granite Reservoir. Since 1975, the U.S. Army Corps of Engineers has dredged sediment from the Lower Granite Reservoir and the Snake and Clearwater Rivers in eastern Washington and northern Idaho to keep navigation channels clear and to maintain the flow capacity.