Years of marsh loss and subsidence along the back levees near Joshua’s Marina in Buras, Louisiana, have compromised the integrity of these levees, which protect this coastal community against storm surge. In an effort to protect this important infrastructure, Plaquemines Parish retained Manchac Consulting group to design a solution.
The total budget for this project was $2.4M with half of the funding from CIAP and the other half from Plaquemines Parish. The CIAP funding had a requirement, which obligated that the funds be used on a living shoreline solution. In general, a living shoreline addresses erosion in lower energy situations by providing long-term protection, restoration or enhancement of vegetated shoreline habitats through strategic placement of plants, stone, sand fill and other structural or organic materials. Living shoreline treatments do not include structures that sever the natural processes & connections between uplands and aquatic areas. For CIAP, the living shoreline concept is limited to the use of artificial oyster reefs for shoreline protection.
The final design consisted of a bioengineered artificial oyster reef breakwater and earthen berm as the two major components. The artificial reef system was installed inside of the marina to protect the surrounding marsh and back levee in this relatively lower wave energy environment. An earthen berm was constructed to the north and south of the marina entrance to stabilize the remaining marsh in front on the levee. To enhance the long term stability of the berm, two engineered products were used to protect the seaward side of the berm. Both of the bank stabilization products utilized a mat-type cover to give immediate protection and are planted with native vegetation to give long term stability and enhance ecosystem services. The construction of this project was completed in November of 2014. The vegetation is already experiencing a great deal of new growth in the short time since it has been planted, and we hope to see the same production out of the artificial oyster reefs in the future.
Please see the attached video link to view the results of the project