Water Resources Research Act Program

Details for Project ID 2020LA032B

Integrated geophysical mapping of a Mississippi Flood Plain Aquifer (0-30 m): 3D seismic and 2D resistivity imaging

Institute: Louisiana
Year Established: 2020 Start Date: 2020-03-01 End Date: 2021-02-28
Total Federal Funds: $15,000 Total Non-Federal Funds: $30,134

Principal Investigators: Juan Lorenzo

Project Summary: Flood-induced seepage under the Mississippi River levees poses an economic risk to the Louisiana industrial corridor, its agricultural economy, state infrastructure and public safety. In order to characterize the soil types and the possible geometries of the pathways for shallow groundwater flow under the man-made levees and into the adjacent floodplain we propose a pioneering 3D seismic deployment coupled with 2D electrical resistivity profiling. We will collect both during the high river stages. By incorporating local core boring descriptions and published relationships between electrical, seismic and soil types we will produce a 3D geological volume of the expected sediment types with a 2-m resolution over a 240 x 36 x 30-m geocube. Our work will focus across two known areas that have experienced significant seepage beneath the levee. Our first study site lies at the northern boundary of LSU’s Baton Rouge campus and where we have previously conducted preliminary geophysical surveys using seismic and electrical resistivity tools during both high and low river stages. This particular area, centered on the Veterinary School Building, already has 5 installed relief wells to counteract groundwater pressure and increase safety but during high-river levels still continues to experience basement and parking lot flooding via seepage. The second site we propose to investigate is also in East Baton Rouge Parish and within a publicly accessible site (Farr Park), approximately 3.3 km south of the first site and has been the focus of recent geotechnical levee reinforcement efforts to counteract seeps.