Proceedings of the 2020 Mississippi Water Resources Conference

Year: 2020 Authors: Chao X., Zhang Y., Jia Y.

The Bonnet Carré Spillway (BCS) of the Mississippi River was constructed from 1929 to 1936 for flood control. In order to protect the city of New Orleans, when the water stage of the Mississippi River approaches 5.18 meters, BCS will be opened to divert the excessive flood water into Lake Pontchartrain and the Gulf of Mexico. The distributions of salinity, sediment, nutrients, and aquatic habitat, in Lake Pontchartrain as well as the Northern Gulf of Mexico, especially the Mississippi Sound are strongly affected by these flood releasing events.

This research is about the application of a two-dimensional numerical model (CCHE2D) developed at the National Center for Computational Hydroscience and Engineering, University of Mississippi, on simulating the dynamic flooding process and associated temporal and spatial distributions of salinity in the Lake Pontchartrain and Mississippi Sound during these flood release events. The simulated results are compared with field measured data provided by USGS and Army Crop of Engineers, and good agreements were obtained. The flow patterns and salinities distribution processes in the lake and Mississippi Sound due to the BCS flood release events are discussed. In addition, the salinity recovery processes in the water were also simulated. The simulation results provides useful information to analyze the environmental impacts of the BCS opening flood events on aquatic ecosystems.