With authorization for the construction of the dam coming forth in 1946, in 1948 the River and Harbor Act (Public Law 80-858 of the 80th Congress, 2nd session) renamed the project Chief Joseph Dam to honour the Nez Perce Chief who spent the last few years of his life in exile on the Colville Indian Reservation in northern Washington.
"Chief Joseph Dam is in Douglas and Okanogan counties, 1.5 miles upstream from Bridgeport, WA and 545 miles upstream from the mouth of the Columbia River at Astoria, Oregon. Its electricity is marketed by the Bonneville Power Administration. Construction began in 1949, with the main dam and intake structure completed in 1955. Installation of the initial generating units was completed in 1958. Eleven additional turbines were installed between 1973 and 1979, and the dam and lake were raised 10 ft, boosting the capacity to 2.620 GW (gigawatts), making Chief Joseph Dam the second largest hydroelectric power producer in the United States. It now has 27 main generators in the powerhouse.
The reservoir behind the dam is named Rufus Woods Lake, and runs 51 mi up the river channel. Bridgeport State Park, on the lake, is adjacent to the dam."
From Wikipedia