Construction of the major impoundments along the Missouri River occurred primarily during the mid-20th century. These large-scale projects significantly altered the river’s flow and ecology, providing flood control, hydroelectric power, and irrigation benefits to the surrounding regions.
The impetus for their creation stemmed from a combination of factors, including devastating floods in the early 1900s, the need for reliable irrigation in the arid western states, and the potential for generating electricity. The Flood Control Act of 1944, also known as the Pick-Sloan Missouri River Basin Program, authorized the construction of a series of dams and reservoirs along the river’s course. This program aimed to manage the river’s flow for multiple purposes, transforming a historically volatile waterway into a more predictable resource.
