Hauser Dam (also known as Hauser Lake Dam) is a hydroelectric straight gravity dam on the Missouri River about 14 miles (23 km) northeast of Helena, Montana, in the United States. The original dam, built between 1905 and 1907, failed in 1908 and caused severe flooding and damage downstream. A second dam was built on the site in 1908 and opened in 1911 and comprises the present structure. The current Hauser Dam is 700 feet (210 m) long and 80 feet (24 m) high. The reservoir formed by the dam, Hauser Lake (also known as Hauser Reservoir) is 25 miles (40 km) long, has a surface area of 3,800 acres (1,500 ha), and has a storage capacity of 98,000 acre-feet (121,000,000 m3) of water when full.The dam is a "run-of-the-river" dam because it can generate electricity without needing to store additional water supplies behind the dam. The powerhouse contains six generators, bringing Hauser dam's generating capacity to 17 MW.