Tieton Dam is an earth and concrete type dam on the Tieton River in Yakima County, in the U.S. state of Washington. The dam began operation in 1925. Its reservoir, Rimrock Lake, has a total capacity of 203,600 acre-feet (0.2511 km³) with a normal operating capacity of 198,000 acre-feet (0.244 km³) to provides water for agricultural irrigation.^[1] This dam is a component of the Yakima Project.^[2] Tieton Dam also produces electricity for Burbank Water and Power and Glendale Water and Power, near Los Angeles. The Southern California Public Power Agency installed two 7 megawatt generators in a project started in 2010. The power is transmitted over the DC Intertie that runs from Celilo, Oregon to Sylmar, California.^[3][2] Upstream from the dam, the river is impounded by Clear Creek Dam, another element of the Yakima Project. About 8 miles (13 km) downstream from the dam, the Tieton River is tapped for the Tieton Main Canal.

Tieton Dam
Tieton Dam and Rimrock Lake from Lava Point
Location	Yakima County, Washington, USA
Coordinates	46°39′23″N 121°7′46″W / 46.65639°N 121.12944°W / 46.65639; -121.12944
Opening date	1925[1]
Operator(s)	United States Bureau of Reclamation[1]
Dam and spillways
Impounds	Tieton River
Height	319 feet (97 m)[1]
Length	920 feet (280 m)[1]
Dam volume	2,049,000 cu ft (58,000 m3)
Reservoir
Creates	Rimrock Lake
Total capacity	203,600 acre-feet (0.251 km3)[1]
Active capacity	198,000 acre-feet (0.244 km3)[1]
Catchment area	184 square miles (477 km2)[1]
Surface area	2,674 acres (10.8 km2)[1]