After hurricane Katrina, a consortium led by DHV conducted a research project in New Orleans in order to improve flood protection and landscape stabilization. DHV advised to recreate salt marshes as a natural barrier against flooding and hurricanes.
A new approach to coastal defenses is becoming visible along the coastal defenses of the American state of Louisiana. An important role has been reserved for the marshes (swamps) in the Mississippi Delta. “Marshes are able to slow down storms and hurricanes. Consequently there will be less flooding of the low-lying areas. If you create new marshes for that purpose, it will also be good for vulnerable eco systems in the fresh-, brackish- and saltwater areas.”
Restoration and the increase of the swamp vegetation is exactly the point of the new reclamation techniques we are developing together with IMARES and Deltares. This technique will be tested as a pilot in the Yankee Pond, situated in a National Park, south-west of New Orleans. The land reclamation in the Mississippi Delta aims at reshaping open water into a swamp again. In a temporary polder the accelerated growth of vegetation can compensate the processes of soil compaction and rising sea levels.
The proposed method is cheaper then the raising and leveling up of the whole area and the building of storm surge barriers.