Abstract submission for the 2015 ASBPA conference Title: Observations of basin-wide dynamics along the lower Mississippi River via in-situ and remotely sensed data Authors: Cyndhia Ramatchandirane1, Brendan Yuill1, Mead Allison1,2, Melissa Baustian1, Ehab Meselhe1 1 The Water Institute of the Gulf, Baton Rouge, LA Department of Earth and Environmental Sciences, Tulane University, New Orleans, LA 2 Poster presentation preferred. Abstract: The Louisiana Coastal Protection and Restoration Authority has presented a Coastal Master Plan that includes developing a network of sediment diversions along the lower Mississippi River. The goal of these diversions is to strategically siphon Mississippi River sediment into its disconnected receiving basins to build and sustain wetlands, offsetting the high rates of regional subsidence and coastal erosion. In order to assess the possible effects and success of this plan, the present study examines complex hydrodynamics, sediment dynamics, and eco-linked parameters in the two basins adjacent to the river near the proposed diversions. Fixed-site instruments were deployed in summer 2014 to measure hydrology and water quality in the Barataria and Breton basins, along with boat deployed transects between stations. Instruments were placed to record the influence of two existing freshwater river diversions at Davis Pond and Caernarvon. While not specifically engineered to divert sediment, these two freshwater diversions are the closest morphological and ecological analogs for the proposed sediment diversions in each basin and are operated seasonally every year. This study reports on the preliminary results of this on-going data collection effort. Results are coupled with remote sensed data to illustrate the present, large-scale spatial and temporal pattern of basin salinity, turbidity, temperature, and chlorophyll a driven by seasonal, storm, and river forcings. These patterns offer 1) insight into a broad array of basin dynamics such as the sediment transport pathways that will benefit future diversion planning and operation, and 2) provide information to parameterize numerical models that will test the impact of the proposed diversions. Primary Author Information: Cyndhia Ramatchandirane is a Research Associate at The Water Institute of the Gulf. She primarily works with the Physical Processes and Sediment Dynamics group led by Dr. Mead Allison. She conducts several field campaigns around coastal Louisiana collecting and processing data that is used to validate and calibrate numerical models that inform various restoration projects. She obtained her Master’s degree in Earth and Environmental Sciences from Tulane University, with Dr. Alex Kolker as her advisor. Her thesis project focused on wetland building on the Chenier Plain coast in southwest Louisiana. Cyndhia Ramatchandirane | Research Associate The Water Institute of the Gulf One American Place 301 N. Main St., Suite 2000 Baton Rouge, LA 70825 O 225-228-2107 | C 650-704-4757 cramatch@thewaterinstitute.org www.thewaterinstitute.org