Lake Oahe Lake Oahe Lake Oahe (oh-WAH'-hee) is a large reservoir behind Oahe Dam on the Missouri River; it begins in central South Dakota and continues north into North Dakota in the United States. The lake has an area of and a maximum depth of . By volume, it is the fourth-largest reservoir in the US. Lake Oahe has a length of approximately and has a shoreline of . 51 recreation areas are located along Lake Oahe, and 1.5 million people visit the reservoir every year. The lake is named for the 1874 Oahe Indian Mission. Lake Oahe begins just north of
Grishk Dam operation in their attempt to blow up the dam. Grishk Dam The Grishk Dam is a dam and power plant on the Helmand River, located in Helmand Province, Afghanistan. It was built by the United States in 1945 for the Helmand Valley Authority for hydroelectric power. The dam is an example of one of the 20th century projects to modernize Afghanistan. A 2003 technical journal noted that the Grishk power plant was commissioned on an irrigation canal in 1945, and had two damaged and obsolete 1.2 megawatt units which would cost US$3 million to repair. In 2005, a group of