Providing Power from the Deschutes River

Round Butte Dam

By Steve Lent, Crook County Historian

Round Butte Dam is located seven miles southwest of Madras near the confluence of the Metolius, Deschutes and Crooked Rivers. The dam was constructed by Portland General Electric (PGE) and placed in service on August 7, 1964. It is a rock and earth fill structure with a height of 440 feet. It has a water storage capacity of 535,000 acre feet of water and can generate 300,000 kilowatts of electric energy. The dam was named for its location just east of Round Butte, a volcanic cone.

PGE began its investigation of the Round Butte location as a potential dam site as early as 1948. Numerous studies had been made by public and private agencies seeking the best sites for developing the power potential of the Deschutes River. In 1951 PGE was issued a preliminary permit and they conducted additional tests and studies. They drilled over 3,000 feet of holes and tested them under pressure to determine the impermeability and solidity of the rock formations. It was determined that the site was a good place to construct a dam.

Prior to building the dam PGE first had to secure the permission of the Confederated Tribes of Warm Springs Reservation as the west bank of the project was on Reservation lands. An agreement was reached in 1959 in which the tribes agreed to a compensation package for what became known as the Pelton/Round Butte complex for a fee of $220,000 per year.

The company received a project license from the Federal Power Commission and the Oregon Hydroelectric Commission. Once construction began over eight million cubic yards of fill material was required to impound the reservoir behind the dam. When it was first built the outdoor powerhouse for three generators was the largest built in the West. The powerhouse is located downstream from the dam and a switch yard is located on the rim to the east of the canyon. The cost of the project was $62 million. A transmission line interconnects with the Bonneville Power Administration grid and also extends westward to a switching point near Salem.

The reservoir behind the dam was named Lake Billy Chinook for an early tribal member. The lake has become one of the most popular recreation sites in Oregon. PGE also constructed an observation park above the dam on the east rim. In 2002 the Confederated Tribes of Warm Springs became a one-third owner of the Pelton/Round Butte Complex. Round Butte Dam is the largest hydro-power project located completely in Oregon.