Hydropower
In the beginning, Otter Tail Power built a series of hydroelectric plants to provide power for its system and these served the company well until its expansion in the 1920s outstripped the dams' capacity (steam provided the bulk of the company's power needs from then on). The company has grown to such a point that today only about 1% of the company's needs still comes from hydropower. The dams are: Dayton Hollow (1909 - southwest of Fergus Falls), Hoot Lake (1914 - east Fergus Falls), Pisgah (1918 - west Fergus Falls), Wright (rebuilt 1922 - downtown Fergus Falls), Taplin Gorge (1925 - northeast of Fergus Falls), and Bemidji (built early 1900s / purchased in 1944). Hoot Lake is unique in that the dam also forms the water intake for the coal-fired power plant nearby.
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