The Missouri River Ecosystem

The Missouri River Ecosystem: Exploring the Prospects for Recovery resulted from a study conducted at the request of the U.S. Environmental Protection Agency and the U.S. Army Corps of Engineers. The nation's longest river, the Missouri River and its floodplain ecosystem experienced substantial environmental and hydrologic changes during the twentieth century. The context of Missouri River dam and reservoir system management is marked by sharp differences between stakeholders regarding the river's proper management regime. The management agencies have been challenged to determine the appropriate balance between these competing interests. This Water Science and Technology Board report reviews the ecological state of the river and floodplain ecosystem, scientific research of the ecosystem, and the prospects for implementing an adaptive management approach, all with a view toward helping move beyond ongoing scientific and other differences. The report notes that continued ecological degradation of the ecosystem is certain unless some portion of pre-settlement river flows and processes were restored. The report also includes recommendations to enhance scientific knowledge through carefully planned and monitored river management actions and the enactment of a Missouri River Protection and Recovery Act.

Historically, the flow of sediment in the Missouri River has been as important as the flow of water for a variety of river functions. The sediment has helped form a dynamic network of islands, sandbars, and floodplains, and provided habitats for native species. Further downstream, sediment transported by the Missouri and Mississippi Rivers has helped build and sustain the coastal wetlands of the Mississippi River delta. The construction of dams and river bank control structures on the Missouri River and its tributaries, however, has markedly reduced the volume of sediment transported by the river. These projects have had several ecological impacts, most notably on some native fish and bird species that depended on habitats and landforms created by sediment flow. Missouri River Planning describes the historic role of sediment in the Missouri River, evaluates current habitat restoration strategies, and discusses possible sediment management alternatives. The book finds that a better understanding of the processes of sediment transport, erosion, and deposition in the Missouri River will be useful in furthering river management objectives, such as protection of endangered species and development of water quality standards.

A tour of the Missouri River and its surrounding area.

The conventional approach to river protection has focused on water quality and maintaining some "minimum" flow that was thought necessary to ensure the viability of a river. In recent years, however, scientific research has underscored the idea that the ecological health of a river system depends not on a minimum amount of water at any one time but on the naturally variable quantity and timing of flows throughout the year. In Rivers for Life, leading water experts Sandra Postel and Brian Richter explain why restoring and preserving more natural river flows are key to sustaining freshwater biodiversity and healthy river systems, and describe innovative policies, scientific approaches, and management reforms for achieving those goals. Sandra Postel and Brian Richter: explain the value of healthy rivers to human and ecosystem health; describe the ecological processes that support river ecosystems and how they have been disrupted by dams, diversions, and other alterations; consider the scientific basis for determining how much water a river needs; examine new management paradigms focused on restoring flow patterns and sustaining ecological health; assess the policy options available for managing rivers and other freshwater systems; explore building blocks for better river governance. Sandra Postel and Brian Richter offer case studies of river management from the United States (the San Pedro, Green, and Missouri), Australia (the Brisbane), and South Africa (the Sabie), along with numerous examples of new and innovative policy approaches that are being implemented in those and other countries. Rivers for Life presents a global perspective on the challenges of managing water for people and nature, with a concise yet comprehensive overview of the relevant science, policy, and management issues. It presents exciting and inspirational information for anyone concerned with water policy, planning and management, river conservation, freshwater biodiversity, or related topics.