Environmental and Water Quality Operational Studies. Morphologic Effects of Lower Mississippi River Dike Fields.
Abstract
Dikes are used extensively on large, meandering rivers to help maintain navigation channels. Dike fields alter flow velocities and sedimentation patterns, thereby affecting river morphology and the amount and quality of aquatic habitat. Some investigators have theorized that sedimentation induced by the dike fields constructed on the lower Mississippi, largely since 1960, is altering river morphology and aquatic hatibat in a manner similar to the changes that have been observed in the lower Missouri. Others are of the opinion that dike fields on the lower Mississippi do not typically fill completely with sediment, and the pools they contain have increased the amount of slack-water habitat. Low-water photographs taken in 1962 and 1976 and comprehensive hydrographic surveys done in 1962-64 and 1974-75 were used to measure morphologic changes in diked and undiked reaches. River surface area between river miles 320 and 954 was classified as main channel, secondary channel, slough, chute, or pool. The 1962 and 1976 areas in each category were measured from the photographs. River stage at time of photography averaged about 2 ft (0.6 m) lower in 1976, so 1976 measurements were adjusted for stage differential, based on width mesurements taken from the hydrogaphic surveys. Results were summarized for diked and undiked reaches.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1986
- Accession Number
- ADA169012
Entities
People
- Linda B. Beverly
- Nelson R. Nunnally
Organizations
- University of North Carolina at Charlotte