On December 2, 1944, the federal Flood Control Act was signed into law by President Franklin Roosevelt. While the stated original intent was to control flooding damage within the Missouri River basin and beyond, the Act served other purposes as well. In a recovering economy, the Flood Control Act of 1944 served as a way to reintroduce jobs to the United States. The construction of the many dams and levees authorized by the act required a huge work force which was just what the country needed in this era. The second unstated benefit was that it could potentially serve to help develop the arid northern Great Plains states through irrigation supplied by the numerous planned reservoirs.

A major component of the Flood Control Act, and one that had an enormous impact on the Northern Plains states such as Montana, North Dakota and South Dakota was the development of the Pick-Sloan Missouri Basin Program which is still in existence today. General Pick of the Army Corps of Engineers and Glenn Sloan of the Bureau of Reclamation each were assigned to develop a plan of development for the "Big Muddy" basin from its headwaters all the way to its mouth at the Mississippi. While each of their plans were similar, they both had different priorities.

Pick's plan outlined flood control, navigation and power generation as the most important outcome of the construction of the many proposed projects. Sloan's priority was for irrigation development throughout the basin. Pick was supported by states in the lower reaches whose economy depended on navigation and not as much by the potential for irrigation water. Sloan's plan had the support of the more northern states that did not historically use the Missouri for navigation, but whose agricultural economies could greatly benefit from the proposed irrigation developments. Ultimately, both plans won out as a brief meeting caused the Corps and Bureau of Reclamation to agree on implementation of each agency's proposals. To this day, the Corps remains responsible for dams on the main stem that control hydropower and navigation, while the Bureau of Reclamation maintains responsibility for the dams on tributaries that provide irrigation water.

The Pick-Sloan Missouri Basin Program had a major impact on lives along the Missouri River corridor and continues to have impacts in the present day. Many individuals lost their land in the reservoir construction, mostly Native American. A great number of irrigation projects were created, although the proposed acreage of irrigable land has yet to be fully realized. And in the modern day, the Pick-Sloan plan has been recognized as having an impact on six major attributes of the Missouri River system: hydropower, recreation, water supply, navigation, flood control, fish/wildlife.

And while all of these attributes are worthwhile, the Corps and Bureau of Reclamation continue to try to create a happy medium between the many often-competing interest groups. It is likely to be a constant competition. Recreationists want water in the reservoirs while navigation interests demand year-round releases. The fish/wildlife segment often competes with the irrigators. After 60 years, the Pick-Sloan program of the Federal Flood Control Act continues to play a major part in shaping the history of the west, specifically in the Missouri River basin. It is a critical component to understanding the culture that exists in the region today.