ENVIRONMENTAL EFFECTS OF EXTREME FLOODS

U.S.- Italy Research Workshop on the
Hydrometeorology, Impacts, and Management of Extreme Floods
Perugia (Italy), November 1995



ENVIRONMENTAL EFFECTS OF EXTREME FLOODS

John T. Hickey
U.S. Army Corps of Engineers
1325 J Street
Sacramento, CA 95814-2922

Jose D. Salas
Department of Civil Engineering
Colorado State University
Fort Collins, CO 80523 USA

Analyzing short and long-term environmental effects of extreme events is a young science.  Complicated by the obvious difficulties associated with predicting extreme events and the hazards of gathering environmental data during and in the aftermath of these often short-lived and violent events, the accumulation of good field data remains an obstacle to a better understanding of quantitative effects.  This article focuses on both the known quantitative relationships and the qualitative aspects of several important natural populations, namely, macroinvertebrate communities, fish assemblages, and river corridor vegetation.  Further, the roles of geomorphic change, structural flood control, and anthropogenic influence in natural environments during flooding events are discussed.  Present flood management policies have severe and far-reaching impacts on natural systems.  Nonstructural flood control measures, including wetland restoration, offer an environmentally sound and feasible alternative to excessive constriction of our rivers with extensive levee systems.