State Water Resources Research Institute Program (WRRI)

Details for Project ID 2011LA79B, 2011

Development of a 2D Hydrodynamic Model of the Mississippi River and Application To Long-Term Management Scenarios, Contaminant Transport and Sediment Transport

Institute: Louisiana
Start Date: 2011-03-01 End Date: 2012-02-28
Total Federal Funds: $15,600 Total Non-Federal Funds: $37,883

Principal Investigators: Clinton Willson, Clinton Willson

Abstract: The Mississippi River has an annual average flow rate of 495,000 cfs (ranks seventh worldwide in both annual sediment and water discharge) and drains approximately 1,245,025 mi2 representing about 41% of the 48 contiguous United States (Knox, 2007) (NAP, 2008). The coastal system that the river created and the ease of passage to/from the Gulf of Mexico for ports up to Baton Rouge make the lower river of vital economic importance to Louisiana and the U.S. The availability of freshwater and ease of navigation has also provided for a large presence on the river of petrochemical plants and related industry. While not a regular occurrence, unintended releases of chemicals within and along the banks of the river occur and can have major consequences for drinking water supplies and ecological systems. Finally, there are a number of proposed projects that intend to utilize Mississippi River water and its resources (e.g., nutrients, sediment) for coastal and wetland restoration projects. Improved understanding of the hydrodynamics of the river and transport of these resources is crucial for optimal planning and utilization. Here, we propose to develop a two-dimensional hydrodynamic model of the Mississippi River from Tarbert Landing out into the Gulf of Mexico that can be used for three purposes: (1) simulate the river hydraulics under potential future scenarios associated with climate change or changes in river management; (2) model the fate-and-transport of chemicals downriver from any location within the study domain; and (3) model the sediment transport dynamics to better understand the timing and delivery of sediment to the lowermost reaches of the river. This model will be useful for state and federal agencies, public officials/decision-makers, researchers and consulting firms in making technically-sound decision regarding the river and its resources. These goals are achievable within the timeframe of the project for two reasons. First, our group has already developed a 2D model of the river from Carrollton, LA out into the Gulf of Mexico. This 2D hydrodynamic model, running on desktop computers and several LSU High Performance computer systems, has been calibrated and validated under a range of conditions (flows, tides) and has been used for oil spill and sediment transport modeling. Second, we have already developed a 1D model of the river from Tarbert Landing to the Head of Passes. This 1D model was built using the latest bathymetry and topography data along the river and has been calibrated and validated for time periods covering more than six months. This same bathymetry and topography will be used to build the 2D model.