9412460 Changnon The 1993 flood on the Upper Mississippi River Basin was a singular event from several perspectives. It ranked as the worst recorded summer season flood with the combined flow at St. Louis achieving a flood level rated as a once in 500-year event. This basin, which typically experiences flood levels in the spring, indeed had spring floods in March-April 1993. However, continuous widespread rains from mid-May through late August brought both the Missouri and Mississippi Rivers and their major tributaries into extreme flooding. The summer season aspect was unique, as was the prolonged nature of the flood on both rivers, lasting between two months and three months at many locations. The floods covered an enormous area and produced one for of the worst natural disasters in the history of the United States. The primary activity of this project will be the collection of all available data related to the floods from mid-1992 through 1993. This will include data on rainfall, stream1flow, water levels in reservoirs including spillway discharges ground water levels, stream water quality, and ground water quality. We will produce a "flood data archive" in digital format. Data that cannot be adequately digitized will be retained and made available in hard copy formats. This database will be made available to all interested scientists and others who desire copies at nominal costs. The archive will be widely advertised in scientific journals, relevant trade journals, and in government-related publications. If interested federal agencies such as the USGS and USEPA wish to help in the distribution of the archive created, these arrangements will be made.
