The project area is experiencing marsh deterioration due to subsidence, rapid tidal exchange, and human-induced hydrologic changes that result in increased salinities. Saltwater intrusion has caused a shift in marsh type and a conversion of over 30 percent of emergent vegetation to open water habitat. Shoreline erosion along the south embankment of Lake De Cade threatens to breach the hydrologic barrier between the lake and interior marshes.
Proposed project components include installing three control structures along the south rim of the lake and enlarging Lapeyrouse Canal to allow the controlled diversion of Atchafalaya River water, nutrients, and sediments south into project area marshes. Outfall management structures are planned in the marsh interior to provide better distribution of river water. In addition, approximately 1.6 miles of foreshore rock dike is planned to protect the critical areas of the south lake shoreline from breaching.
The project is located in Terrebonne Parish, approximately 15 miles southwest of Houma, Louisiana.
After initial engineering investigation, the project was divided into two construction units. Construction unit one consisted of the shoreline protection only and was completed in July 2011. Construction unit two consisting of the freshwater introduction component was further investigated and due to uncertainty of benefits was not constructed, and therefore, the project is considered completed.
This project is on Priority Project List 9.
The Federal Sponsor is NRCS
The Local Sponsor is CPRA