On Feb. 27, 1954, the U.S. government took additional land from the Yankton Sioux Tribe to build the Fort Randall Dam and Reservoir in southeastern South Dakota. That dam and four others built on the Missouri River by the Army Corps of Engi...neers from 1946 to 1966 were approved for flood control, pollution and sediment control, navigation, conservation, recreation, hydroelectric power and enhancement of fish and wildlife under the Pick–Sloan Missouri Basin Program, a part of the Flood Control Act of 1944.

Construction of the dams and consequent flooding forced the relocation of more than 1500 Indian families on seven reservations, including some 136 on the Yankton Reservation. The tribes lost more than 350,000 acres. Besides the Yankton Reservation, fertile bottom land was condemned on reservations at Fort Berthold, Cheyenne River, Standing Rock, Lower Brule, Crow Creek and Santee.

The tribes didn't only lose their land but also any timber, wildlife and native plants plus homes and ranches. In the case of Fort Thompson on the Crow Creek Reservation, an entire town was inundated. As a consequence, the BIA and Indian Health Service offices were moved off the reservation to Pierre, making it far more difficult for Indians they were supposed to serve to use them.

The losses also included spiritual ties to the land and the intangible benefits that came from living along the Missouri.

The tribes were never consulted about the project during the planning stages. No Indians were asked to testify during hearings on the projects in Congress. The Bureau of Indian Affairs, which supervises Indian land held in trust by the Department of Interior, raised no objections.

The Corps of Engineers handled negotiations. Tribal sovereignty and treaty rights, including the Yankton Treaty of 1858, were completely ignored. So also was the Winters Doctrine, a Supreme Court ruling that Indians have inherent rights to water resources on their lands. Philleo Nash, who had advised Presidents Roosevelt and Truman to integrate the Armed Forces and later served as BIA Commissioner under JFK and LBJ, would later say that Pick-Sloan "caused more damage to Indian land than any other public works project in America."
U.S. officials and representatives of the Three Affiliated Tribes
(Hidatsa, Mandan and Arikara) sign the Garrison Dam agreement

June 11, 1953. The officials are not the ones crying.
The amount of money offered to owners of individual Indian land allotments was often significantly less than the amount offered to non-Indian land owners. Likewise, as the dam projects began in a time when termination of reservations was in full swing, government compensation for damages caused by the taking of communally owned tribal land was well below its market value. Land at North Dakota's Fort Berthold Reservation of the Mandan, Hidatsa and Arikara people was condemned and bought for $33 an acre. Today, the earthen Garrison Dam is on the land, holding back Lake Sakakawea, and capable of generating some 583 megawatts of electricity. Twenty-five years after the last dam was completed, the General Accounting Office undertook the first of four reports on providing better compensation, which you can see here: 1991; 1998; 2006; and, 2007

Today, the tribes whose land was taken have an on-reservation population of about 32,000, with another 20,000 enrolled members living elsewhere.

Suggested book - Dammed Indians: The Pick-Sloan Plan and the Missouri River Sioux, 1944-1980

More info: http://plainshumanities.unl.edu/encyclopedia/doc/egp.wat.019