Project Location
The project is located in the Terrebonne Basin, in Terrebonne Parish, Louisiana
Project Description
The project helped to maintain and restore the North Lake Mechant landbridge in Terrebonne Parish (Lake Mechant north shoreline and the Small Bayou La Pointe Ridge) by creating and nourishing 604 acres of marsh using 5.1 million cubic yards of sediment dredged from North Lake Mechant. Other project features included planting smooth cordgrass (Spartina alterniflora) on the shoreline, the construction of various plugs, and repairing a fixed-crest weir along Bayou Raccourci.
Issue Addressed
The project would protect and restore a critical landbridge barrier between the easily erodible fresh marshes north of Bayou De Cade and the higher saline environment of Lake Mechant. At the present shoreline erosion rate, the north Lake Mechant shore will soon fail to act as a barrier, allowing the hydrologic connection between Lake Mechant and the fresher marshes to the north. In addition, erosion and deterioration along the banks of Raccourci Bayou are threatening to enlarge and straighten this winding tidal pass into a major conduit for water exchange. These changes will accelerate the loss of the
remaining interior marshes, extend lake-like conditions, and increase salinities north to Bayou De Cade. Should shoreline breaching and enlargement of tidal
channels allow high tidal energy conditions to intrude into the project area, the organic interior marshes would likely experience increased loss rates.
Project Goals
Dredged material from northern Lake Mechant will be used to create marsh. Smooth cordgrass (Spartina alterniflora) will also be planted along the shorelines of Lake Mechant, Goose Bay, and Lake Pagie. The project will also repair breeches formed by erosion and oilfield access canals which threaten the integrity of the landbridge.
Verify Date
1/15/2020