Proposed Restoration Measures: Wetlands Creation and Restoration

Wetlands Creation and Restoration Measures

This component of the feasibility study will develop projects to restore and create wetlands in the southwestern Barataria Basin. The goal of the projects is to protect and sustain ecological functions, including wetlands and wooded ridge habitat. Measures being considered include those described letters "A" through "I."

1 Bayou L‘Ours North Unit

(C) Create/Nourish Marshes
(I) Protect Shoreline

2 Bayou L‘Ours South Unit

(C) Create/Nourish Marshes
(E) Fill, Plug and Isolate Canals

3 Caminada Unit

(C) Create/Nourish Marshes
(I) Protect Shoreline

4 Chenier Unit

(A) Buy Land/Obtain Conservation Easement
(B) Restore Ridges
(C) Create/Nourish Marshes
(D) Create and Enhance Wooded Habitat
(E) Fill, Plug and Isolate Canals
(F) Develop Educational / Recreational Area Next to LA Highway 1 in Chenier Unit
(G) Degrade Impoundment Levee in Chenier Unit
(H) Terrace Open Areas

5 Leeville Unit

(C) Create / Nourish Marshes
(D) Create and Enhance Wooded Habitat
(E) Fill, Plug and Isolate Canals

(A) Buy Land/Obtain Conservation Easement
Listed as imperiled to critically imperiled, the maritime forest habitat in the Chenier Unit is some of the last remaining in Louisiana. Where commercial development is likely, an option to acquire control of the land will be considered. Placing the land under state control will prevent both unwanted development and land rights issues from hampering future conservation efforts.

(B) Restore Ridges
Expanding the chenier ridges that support maritime forest habitat includes rebuilding subsided ridges, replanting native woody species and creating marsh between ridges, as well as pairing with marsh creation to offset any habitat conversions. Material will be obtained off-site or from degrading impoundment levees and spoil banks.

(C) Create/Nourish Marshes
This measure, which also addresses land-bridge restoration, uses fill material from off-site. There are two main placement areas: open water with little or no existing marsh remaining, and broken marsh with few spoil banks.

(D) Create and Enhance Wooded Habitat
Existing spoil banks and other features with higher elevations will be used as a framework to create wooded habitat. Additionally, the steep sides typical of spoil banks will be reduced and a vegetation and elevation gradient created—with woody species on higher elevations, grading down to marsh vegetation at lower elevations—providing an ecological link from the upland habitat to the marshes. The higher areas will stabilize adjacent marshes and be constructed primarily of material from spoil banks as they are breached for hydrologic restoration.

(E) Fill, Plug and Isolate Canals
Where canals act as a conduit for tidal flow into areas that historically had much slower or non-existent tidal currents, filling, plugging or isolating the canals will restore the hydrology to more natural conditions.

(F) Develop Educational/ Recreational Area Next to Highway 1 in Chenier Unit
Because of the proximity of LA Highway 1 to maritime forest habitat, the opportunity exists to create a facility for bird watching and fishing. This will consist of a parking area with access to a boardwalk and observation tower.

(G) Degrade Impoundment Levee in Chenier Unit
Degradation of portions of the mariculture impoundment levee would restore a more natural hydrology to the impounded area, allow natural sediment introduction and reduce the land-loss rate. Material from the levee will be used to fill borrow pits used for its construction, restore ridges or create additional wooded habitat.

(H) Terrace Open Areas
Terracing, while creating some marsh, primarily protects existing marsh habitat by preventing erosion and trapping the limited sediment supply. Sediments in this area are particularly suited for terracing. Material will be dug from adjacent water bottoms where appropriate.

(I) Protect Shoreline
Shoreline protection will consist of offset, segmented, foreshore dikes. These dikes will protect marshes from erosion in areas of rapid shoreline retreat. Material used will be imported, as the adjacent sediments would be unsuitable.