Losing Louisiana The wetlands of the Mississippi delta are disappearing fast with far-reaching implications for the Cajun community
Written by Tim
The American state of Louisiana is losing about 25,000 acres of wetlands a year, that’s one American football field every 30 minutes. The wetlands are turning to open water in what is described by scientists as the “Swiss cheese effect”.
Known by locals as the heart of the American machine, the Louisiana wetlands provide ecosystem services. Twice the size of Florida’s Everglades, they ranked second only to Alaska in commercial fish landings and act as a crucial buffer zone protecting the communities of the Mississippi delta from storm surges in the Gulf of Mexico. The region also transports or produces a third of America’s oil and a quarter of its natural gas.
However, a conspiracy of factors is forcing the wetlands underwater. Alluvial deposits naturally subside over time unless topped up with fresh layers of sediment but the levees have been raised so high along the Mississippi that the sediment is channelled straight into the deep waters of the Gulf. Subsidence rates have accelerated because the extraction of oil and gas extraction has caused a drop in underground pressure causing slumping of the land above. And since the 1950s countless channels have been cut and dredged through the wetlands to service these oil and gas facilities, increasing the surface area of coastline exposed to wave action, exacerbating the erosion problem.
For Mike Arcenaux, resident of Pointe-aux-Chenes a narrow terrestrial finger in this watery world, the loss threatens Cajun culture which is rooted in the land with a strong emphasis on self-sufficiency and surviving off nature. Even the eponymous oaks of Pointe-aux-Chenes are under threat from saltwater intrusion and swathes of oaks and cypress trees stand dead in the surrounding brackish waters. Today there is a long waiting list of homeowners wanting to raise their houses on stilts above the increasingly frequent floodwaters. “Every mile of marsh reduces storm surge by a foot” Arcenaux told us “and we’re losing it fast”.
With every new hurricane and every subsequent clear-up effort residents are faced with a decision: whether to restore or retreat. “We must be crazy to live here but if you’re hard-headed like my family you don’t want to leave” Arcenaux said. “ But I’m not sure if my daughter or her children will even have the choice.”