The Thompson Falls Hydro Project, the $85 million Noxon Dam and Powerhouse were built in the years 1956 to 1959. The earth filled gravity dam itself is a mile long, 260 feet high and 700 feet wide at the base, providing a head of something over 150 feet at the turbines.
The powerhouse measures 485 feet by 105 feet and required 69,952 cubic ards of concrete and 3,220,977 pounds of reinforcing steel. Concrete work was concluded on July 3, 1959 and the powerhouse went online that same month. By 1977, after the addition of the fifth generator, the dam was producing 554 megawatts of power.