CASE STUDIES

Plaquemines Parish: Coastal Restoration Program

Wetlands within Plaquemines Parish have undergone substantial loss due to subsidence, sea-level rise, and salt-water intrusion. The wetland habitat is showing severe signs of stress and deterioration and is being replaced with open water throughout the basin. Without enrichment from sediment material and a stable marsh platform, the open water areas will continue to increase placing additional stress on the hurricane levee systems that provide flood protection to the residents of Plaquemines Parish.

To address this problem, the Parish of Plaquemines selected a Coastal Restoration Team to develop a design concept that would provide both coastal restoration and flood protection for the residents of the parish. The team includes Burk-Kleinpeter - providing engineering services, Coastal Environments - providing environmental expertise, Griffin Services - in charge of land acquisition, Dr. Joseph Suhayda - providing expertise as a hydrologist, and GCR Inc. - providing project and team management. The team considered several design concepts and chose the “Forested Ridge” concept because of its ability to meet the needs for protection and restoration.

The project’s objectives are:

1. Prevent further erosion of the marsh area immediately adjacent to the levees;
   
   
2. Stabilize existing marsh areas by filling with sediment; and
   
   
3. Create a transitional wetland area that will result in the development of a "Forested Ridge" immediately adjacent to the existing levee system.

This project will provide stabilization to the existing brackish marsh through enrichment with freshwater nutrients and sediment from the Mississippi River. It also includes infilling of the open water areas that currently penetrate the brackish marsh, and establishing transitional wetland vegetation between the marsh and the back levee.

Reach B-2, 8 miles long, will be the “pilot” to demonstrate the potential of benefit to both coastal restoration and flood protection.

In addition to project management services, GCR was responsible for scheduling and management of all tasks required for the development of a Joint Permit Application for the development of Reach B-2 of the Coastal Restoration Program.