Submitted to: International Conference on Water Resources Engineering Proceedings
Publication Type: Proceedings
Publication Acceptance Date: April 1, 1998
Publication Date: N/A
Interpretive Summary: Understanding the channel evolution within streams requires a systematic approach especially when applying appropriate erosion control measures within a watershed. Measured surveys within the Goodwin Creek Watershed (GCW), a part of Mississippi's Demonstration Erosion Control Project Long Creek Watershed, were periodically performed to determine changes in the channel. A computer simulation tool has been developed to effectively evaluate design decisions needed to improve the water quality of watershed systems. This study presents results from the simulation of erosion and sedimentation within and along channels in GCW. This tool was able to accurately reflect measured individual storm and long term watershed runoff, erosion, and channel evolution within GCW. This information is important to agencies such as USDA-NRCS and the US Army Corps of Engineers in understanding and designing a system of measures within a watershed to prevent erosion and sedimentation, thus decreasing construction and maintenance costs.
Technical Abstract: Channels in the Yazoo River Basin in northern Mississippi have incised considerably during the past few decades due to knickpoints migrating up the channels. Federal action agencies have coordinated their work within the Mississippi Demonstration Erosion Control Project (DEC) watersheds to install grade control structures needed to stabilize channels. These structures prevent the upstream migration of knickpoints and ultimate heightening of streambanks, which otherwise would lead to mass bank failure and therefore loss of farmland. The response of channels to grade control structures is not well understood since many interactions between hydrologic, hydraulic, and geomorphic parameters are involved, thus eliminating the use of simple, analytical tools. The results of computer model simulations of channel evolution of Goodwin Creek, Mississippi, demonstrates the capability of these tools to accurately predict the longitudinal morphology of incised channels within watershed systems.