The 1993 Flood on the Upper Mississippi and Missouri Rivers is now
considered the largest flooding event on these river basins. Not
only were many miles of the rivers flooded, but there was also a
significant amount of flooding to the interior of the country.
More than 420 counties in all the midwestern states were declared
disaster areas. Stages were exceeded many locations, hundreds of
levees either failed or were overtopped, more than 500 scour holes
developed, the rivers scoured their beds at numerous locations,
sediments were deposited at many other locations, and the rivers
attempted to create new channels and/or cutoffs during the peak
periods.
This paper is not intended to summarize the various factors
associated with this flood. A number of excellent reports have
been published on the 1993 flood, and readers are referred to
these reports for further information. They are: Bhowmik et al.,
1995, 2nd Edition; Illinois Department of Energy and Natural
Resources, 1994; Chrzastowski et al., 1994; Interagency Floodplain
Management Review Committee, 1994; Interagency Floodplain
Management Review Committee, Part V, 1994; U.S. Army Corps of
Engineers, 1994a, 1994b, 1994c; and Dowgiallo, ed., 1994. So many
articles in newspapers, journals, and popular magazines have been
written about the flood that it would be almost impossible to cite
all of them.
It is worth noting that the International Water Resources
Association published a special issue of Water International in
December 1994 on "The Great Flood of 1993" that features seven
articles prepared by various experts, including an editorial by
Bhowmik and Demissie (1994).
The main topic covered in this paper is the impact of the 1993
flood on erosion, scour, sediment transport, channel alternation,
sedimentation, and water qualities of both rivers. A very brief
summary will be included to inform the readers about the
background of this flood.
