Also known as "Big Muddy," the Missouri River meanders 2,341 miles from its origins in the Rocky Mountains of Montana before joining the Mississippi River at St. Louis, Missouri. The river drains roughly one-sixth of the United States, including portions of ten states, the homelands of twenty-eight Native American tribes, and a small portion of Canada. Before 1940 this great river was almost completely uncontrolled.
A series of extreme droughts during the 1930s and severe flooding in 1943 that covered many areas along the Missouri River, including much of Omaha and Kansas City, prompted a surge of interest in water planning for the Missouri River basin. Planners felt that increased management of the river and its tributaries would not only reduce future flooding, but also benefit the region’s economy through increased irrigation and hydropower production, enhanced navigation, and job opportunities for veterans returning from World War II. Two federal agencies, the U.S. Bureau of Reclamation and the U.S. Army Corps of Engineers, were the leading water development agencies at the time, and both were called on by Congress to compose plans to harness the unruly river. The Bureau of Reclamation’s subsequent plan, sponsored by William G. Sloan, focused on increasing irrigation for agricultural stability and hydropower production for regional economic growth. The Corps of Engineers's plan, sponsored by Col. Lewis A. Pick, concentrated primarily on reducing floods and increasing navigation within the basin. The two plans were eventually merged into the Missouri River Basin Development Project, commonly known as the Pick-Sloan Plan, during a conference in Omaha, Nebraska, on October 17, 1944. The combined plan was submitted to Congress and enacted on December 22 as part of the Flood Control Act of 1944. In appreciation of Colonel Pick and William Sloan's efforts in the development of the plan, the project was officially dedicated as the Pick-Sloan Missouri Basin Program in 1970.
Under the initial $1.9 billion plan, 316 separate projects were authorized, aiming to create 112 dams, 4.3 million acres of irrigation, 2.6 million kilowatts of hydroelectric generating capacity, and hundreds of miles of levees and other flood protection structures. The highlight of the plan was to be the construction of five, large multipurpose dams along the upper main stem of the Missouri River: Garrison, Oahe, Big Bend, Fort Randall, and Gavins Point, along with improvements to the previously constructed Fort Peck Dam in Montana. Under the compromise, the Corps of Engineers would determine reservoir capacities for flood control and navigation and the Bureau of Reclamation would determine capacities for irrigation. The following year, Congress also authorized the Missouri River Bank Stabilization and Navigation Project under the 1945 Rivers and Harbor Act, which allowed for a nine-foot-deep navigation channel to be created on the Missouri River downstream from Sioux City, Iowa. Together, these projects constitute the majority of engineering works on the Missouri River.
To assist in the cooperative management of these projects, Congress authorized the establishment of the Missouri Basin Inter-Agency Committee in 1945, consisting of various federal and state members. The name and structure of this committee has changed several times over the years. In 2001 it was known as the Missouri River Basin Association to reflect the addition of tribal and other interest groups. Through these cooperative efforts, the region was to receive a fair allocation of flood control, enhanced navigation, cheap hydroelectric power, irrigation, and programs to increase public recreation facilities, municipal and industrial water supplies, and fish and wildlife populations. However, since the inception of the Pick-Sloan Plan, many environmental, water rights, and cost-benefit issues have arisen that have forced planners to revise the design and operation of projects. So many concerns surfaced that in 1964 Congress mandated that any Pick-Sloan project not yet initiated would have to be authorized by Congress. Although most of the primary projects have been completed, many other works have been modified, are still under review, or have been eliminated.
The region has received many significant benefits from the Pick-Sloan Plan. Farms, residences, and businesses worth approximately $17.6 billion benefit from flood control measures provided by the mainstem reservoir system. Generated hydropower provides more than 9 percent of the energy use in Iowa, Minnesota, Nebraska, North Dakota, and parts of Illinois, Montana, and Wisconsin. Many irrigation projects were eventually scaled down or eliminated because of inappropriate soil types or lack of interest, but there are approximately 1,600 water intakes on the mainstem reservoir system, supplying much-needed water for municipal, agricultural, industrial, and domestic water uses. In addition, the river and its lakes provide recreational opportunities that contribute $87.1 billion annually to basin states as well as benefiting navigation on the lower river.
Although these and other benefits have been derived from the Pick-Sloan Plan, the project has also caused significant problems for many local people and the natural river ecosystem. Filling the dams involved flooding approximately 1.6 million acres of fertile bottomlands along the river and the voluntary or forced relocation of thousands of people, including more than 900 Native American families. Damming of the upper portions of the river and channelization of the lower reaches have also created new ecosystems to which plants and animals have been forced to adapt. On the upper reaches, lake environments have replaced much of the free-flowing river, and interlake reaches are affected by lower water temperatures and reduced sediment loads. On the lower river, channelization has reduced river depth diversity and eliminated sandbars and river connections with side channels and backwaters. Natural river flows have also been transformed, with high spring flows now captured in reservoirs and low summer and fall flows supplemented with reservoir releases. These modifications have caused significant changes to the habitats and populations of many river fish and bird species, some to the extent that they are now federal- or state-listed as endangered or threatened species or species of special concern.
Overall, the Pick-Sloan Plan has provided local states and tribes with significant benefits. The project has brought much-needed revenue, employment, flood control, cheap hydroelectric power (to some portions of the region), enhanced navigation, recreation, water supply, and a host of other benefits to an economically depressed area. However, this development comes at a great cost. Besides the ever-increasing amounts of money spent on construction and management of the project, other losses have been incurred that cannot be calculated. The cultures and livelihoods of people relocated by the projects were often severely disrupted, and the natural ecosystem of the river has been forever altered. Because of such concerns, attempts are now being made to take a more balanced approach to water management within the Missouri River Basin.
Cody L. Knutson University of Nebraska-Lincoln
Ferrell, John R. Big Dam Era: A Legislative and Institutional History of the Pick-Sloan Missouri Basin Program. Omaha: U.S. Army Corp of Engineers, 1993.
Lawson, Michael L. Dammed Indians: The Pick-Sloan Plan and the Missouri River Sioux, 1944–1980. Norman: University of Oklahoma Press, 1982.