One-Dimensional Modeling of Sedimentation Impacts for the Mississippi River at the West Bay Diversion

Jeremy A. Sharp, Ronald E. Heath, Nathan D. Clifton

USACE Engineering Research and Development Center, Coastal and Hydraulics Lab, Vicksburg, USA.

DOI: 10.4236/jwarp.2013.59A002                

Abstract

The Coastal Wetlands Planning, Protection and Restoration Act (CWPPRA) funded construction of the West Bay Sediment Diversion Project (WBSD) on the west bank of the Mississippi River for the purpose of coastal restoration. A multi-tiered sediment study for the WBSD was conducted to determine impacts to the adjacent navigation channel and to the Pilottown Anchorage Area (PAA). One tier of the study is the implementation of HEC-6T, a one-dimensional (1-D) sediment model, to evaluate the regional impacts of the WBSD. The HEC-6T model results shows the long-term channel changes associated with the WBSD to be increasing shoaling in the adjacent areas on the order of 10% - 20%, as compared to the no WBSD condition. However, it is extremely difficult to isolate the impacts associated with a single diversion due to multiple diversions in the region. From a holistic vantage point, the 1-D model shows the necessity to examine, on a regional scale, the lower Mississippi River as a single congruent system on a regional scale.

Keywords

Diversion; Dredging; Mississippi River; Navigation; Sediment

Conflicts of Interest

The authors declare no conflicts of interest.

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