Bratsk Dam, gravity earth-fill dam on the Angara River, Russia, completed in 1964. The dam is 410 feet (125 m) high and 14,488 feet (4,417 m) wide at the crest and has a volume of 14,337,000 cubic yards (10,962,000 cubic m). It creates an unusually large reservoir of 137,227,000 acre-feet (169,270,000,000 cubic m) and has an electric power capacity of 4,500 megawatts. Concrete buttresses support a two-lane highway that runs across the downstream face of the dam’s crest.
The dam was built under very difficult conditions. Siberian winter temperatures fall as low as -72° F (−58° C), and there is frost 281 days per year. Bratsk is remote from materials, labour supplies, and construction facilities. It is the second of four power stations on the Angara River. The others are Irkutsk, Ust-Ilim, and Boguchany.