Chief Joseph Dam, Rufus Woods Lake, and associated facilities are operated for Hydropower, Irrigation, Recreation, and Water Quality. Chief Joseph Dam was originally authorized as Foster Creek Dam in the River and Harbor Act of 1946 for power and irrigation. The project was renamed Chief Joseph Dam in the River and Harbor Act of 1948. Construction began in 1949, and the first eight generating units were brought online in 1955. Eight more units were completed in 1958, then eleven more in 1979, to total 27 units. The construction of Chief Joseph Dam on the Columbia River created Rufus Woods Lake, which extends upstream for a distance of 51 miles.