Pelton Dam is a major dam on the Deschutes River in Jefferson County, Oregon, owned and operated as a hydroelectric facility by Portland General Electric, one element of its Pelton Round Butte Project on the Deschutes.
The concrete arch dam at Pelton dates from 1958, has a height of 204 feet from bedrock, a width of 965 feet at its crest, and generates 110 megawatts of electricity.
Upstream, to the south, Pelton Dam impounds the waters of the Deschutes to create the deep Lake Simtustus in a relatively narrow canyon about seven miles back to the 1964 Round Butte Dam. The lake has a surface area of about 540 acres and holds 33,190 acre-feet. The name "Simtustus" honors a native who scouted for the U.S. Army during the 1867-68 campaign against the Paiutes.
Downstream, to the north, a regulating dam two and half miles controls the river flow. The area between is called the Pelton Regulating Reservoir. In 1982 the Confederated Tribes of Warm Springs installed a hydroelectric turbine unit in the regulating dam for additional power. Between 2000 and 2005 the CTWS also asserted itself as a stakeholder in the project's re-licensing negotiations between Portland General Electric and the Federal Energy Regulatory Commission, winning key environmental, cultural, and water rights concessions.