The history of Walla Walla District is closely linked to the development of water resource projects on the Columbia and Snake rivers. Establishment of the District in 1948 coincided with the start of work on McNary Dam on the Columbia River near Umatilla, Oregon, slightly downriver from the Tri-Cities area in Washington.
The Walla Walla District is the second largest hydropower producer in the Corps of Engineers, providing a total generating capacity of 4,413 megawatts to the Federal Columbia River Power System. McNary Lock and Dam can produce 980 megawatts of electricity from its 14-hydropower turbines. The four lower Snake River projects have a combined total generating capacity of 3,033 megawatts from 24 turbines. Dworshak Dam, near Orofino, Idaho, has three hydroelectric turbine units, which can generate 400 megawatts of power for the region.