|Shields Jr, Fletcher|
Submitted to: North American Water and Environment Congress Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 7/15/1996
Publication Date: N/A
Interpretive Summary: Scientific studies of warmwater stream restoration projects are rare, and appropriate methods for gaging the success or failure of stream habitat restoration projects are poorly defined. Physical (low flow water velocity and depth) and biological (fish) effects of restoration were observed in two badly eroded stream channels in northwest Mississippi. Contemporary data were collected from three other streams to serve as points of reference. Restoration effects were generally positive, though short-lived at one site. These experiences will allow engineers to incorporate aquatic habitat restoration elements into standard watershed stabilization projects, and aid scientists in developing monitoring plans for these projects.
Technical Abstract: Fish and physical habitat were sampled from five 1-km stream reaches in northwest Mississippi during Spring and Fall for five years. Two of the reaches (HC and GC) were modified by adding vegetation and structure to rehabilitate habitats degraded by erosion and channelization during the course of the study. The other three reaches provided reference data, as two of them were degraded but not restored and the third was only lightly degraded. Restoration had small and short-lived effects on water depth and velocity at HC, but at GC led to a 169% increase in mean depth with attendant 63% decrease in mean velocity. These trends made the restored sites more similar to the lightly degraded reference site and less similar to the degraded reference sites. Fish exhibited generally positive responses to restoration, but causes for some concurrent changes in fish populations in reference reaches could not be definitely ascertained. Aquatic habitats may be rapidly restored to badly degraded warmwater streams, but ensuring sustainability of restoration projects and measuring their effects is problematic.