McNary Lock and Dam was authorized by the River and Harbor Act of 1945. The project includes a powerhouse, navigation lock, two fish ladders, a removable spillway weir and a juvenile fish bypass facility. It provides navigation, hydropower, recreation and incidental irrigation. The dam, located on the Columbia River, is 7,365 feet long, rising approximately 183 feet above the streambed. It is a concrete gravity type dam, with an earthfill embankment section.

Lake Wallula, the project’s reservoir, offers a variety of recreation opportunities such as fishing, swimming, picnicking, boating, hunting, hiking and camping.