 The dam was constructed in 1971 by TransAlta.The Bighorn Plant has a generating capacity of 120 megawatts (MW), and has an available water supply that allows it to be the largest producer of hydroelectric electricity in Alberta, with an average of 408,000 megawatt hours (MW.h) each year.One of the North Saskatchewan's major tributaries, the Brazeau River, houses the Brazeau Hydroelectric Plant.