The Devils Lake Basin is a 3,810-square-mile (mi2) closed basin in the Red River of the North Basin, in North Dakota. Due to to increased precipitation since the early 1990's the lake level in the two lakes, Devils Lake and Stump Lake in the basin have risen markedly. The Devils Lake Basin contributes to the Red River Basin only when the level of Devils Lake is greater than 1,459 feet (ft) above sea level (asl). At an elevation of about 1,447 ft asl, Devils Lake begins to spill into Stump Lake; and at an elevation of about 1,459 ft asl, the combined lakes begin to spill through Tolna Coulee into the Sheyenne River (a tributary of the Red River). In 1999 Devils Lake began to spill into Stump Lake but has not risen enough by 2007 to overflow though Tolna Coulee; however it has flooded considerable farmland and forced relocation of highways and railways and construction of levees at a cost of $500 million.
An outlet, Devils Lake Outlet, has been constructed and was put to use in June, 2007. It is not sufficient to prevent further rise of lake level if current trends continue, but only to slow it.