Volumes of recent floods and potential for storage in upland watershed areas of Iowa

Abstract

Substantial flooding at various locations throughout the United States, particularly during and after the Upper Mississippi River Basin flood of 1993, has resulted in analysis and discussion of both structural and nonstructural methods of watershed management to control flooding. The Upper Mississippi River Basin flood of 1993 resulted in the formulation of a Scientific Assessment and Strategy Team (SAST) to assist and advise decision makers about the positive and negative effects of flood-control measures and habitat restoration (Scientific Assessment and Strategy Team, 1994). SAST recognized the role of upland processes and the interconnectivity of a management strategy on other parts of the river system. If upland areas are considered for inclusion in an overall management strategy related to flooding, an analysis of watershed that have been flooded and the amount of runoff generated during those floods is needed. During the autumn of 1997, the U.S. Geological Survey (USGS), in cooperation with the U.S. Environmental Protection Agency, began a study to determine the volume of water associated with recent flood events in parts of the Midwestern United States and a preliminary evaluation of the potential upland areas for storage of flood-waters in selected watersheds. This analysis, although preliminary, may be useful in determining the feasibility of conducting additional, more detailed studies into the role of upland areas in a watershed management strategy. The methods and results of this preliminary hydrologic study are presented in this report.