An impoundment of the Tieton River, Rimrock Lake's capacity and discharge is controlled by Tieton Dam, a 319-foot (97 m) high structure built in 1925.

[1] Upstream from the lake, the Tieton River is impounded by Clear Creek Dam, another element of the Yakima Project.

The canal supplies irrigation water to the Tieton Division of the Yakima Project, with excess and agricultural runoff draining into Ahtanum Creek, west of Yakima.

The lake flooded the site of a Yakama village named Miya’wax and portions of the Yakama-Cowlitz Trail which connected the Yakama people east of the Cascade Range to the Cowlitz people west of the mountains.

This Yakima County, Washington state location article is a stub.