Pelton Dam



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 ft from bedrock, a width of 965 ft 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 7 mi back to the 1964 Round Butte Dam. The lake has a surface area of about 540 acre and holds 33190 acre ft of water. The name "Simtustus" honors a native who scouted for the U.S. Army during the 1867–68 campaign against the Paiutes.

Downstream, 2.5 mi north, a regulating dam 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.

On June 29, 2021, Pelton Dam recorded a temperature of 119°F (48.3°C), making it the third time Oregon’s highest temperature was recorded. Prineville recorded a temperature of 119°F on July 28, 1898, and Pendleton recorded the same temperature shortly after on August 10 that same year.