Southern Louisiana’s Vanishing Act

by | 4.20.2011 at 7:00am | 3 Comments
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Drawbrigdes, like this one outside of Lake Charles, are ubiquitous across Southern Louisiana's marshy landscape. 2010, photo by Benjamin Preston

If you’ve ever been to New Orleans, Louisiana, you will no doubt recall colorfully-painted Spanish- and French-styled buildings, sparkling green, gold and purple plastic beads, and, of course, the imposing sheen of the Mississippi River as it snakes past the city. But outside the city limits, a sprawling complex of wetland habitat tucks the Big Easy into a protective pocket, keeping it and its 350,000 or so inhabitants safe from the ravages of hurricanes. Hurricanes are regular visitors to the area, but so is coastal erosion, and it’s threatening the very existence of places like New Orleans, Houma, Grand Isle, and a host of other population centers along Louisiana’s swath of Gulf Coast land.

There’s no doubt about it — Southern Louisiana is vanishing. According to a 2004 report by Southern University professors Lionel D. Lyles and Fulbert Namwamba, “Louisiana loses one acre of land every 24 minutes.” Over the past 50 years — the time since high levee building kicked into high gear, Louisiana has lost as much land area as it took the Mississippi River nearly 2,500 years to generate. Currently, a river that was once part of the delta fan it created is completely isolated from it, and there are calls to create diversions into marshland to aid wetland replenishment.

A satellite view of the Mississippi River Delta. 2001, NASA image

Driving, boating, even walking through Southern Louisiana is a unique experience. Moist air hugs the watery landscape in a comforting blanket, coloring sunrises and giving ancient, long-necked birds mysterious banks of mist from which to emerge as they flap their wings deliberately to gain altitude. Along the Atchafalaya River – a small but voluminous waterway spilling away from the Mississippi River not far upstream from Baton Rouge – fishermen in narrow fiberglass pirogues dart in and out of off-channel swamp canals to collect huge nylon net sacks full of crawdads. The little crustaceans are the poor man’s lobster, and every bit as good if you have a sixpack of cheap lager handy. Once in a while, a green-gray log along the riverbank moves, turning out to be an old ‘gator catching some of the sun’s warmth.

The region is a hive of coastal economic activity. Aside from fishing, crabbing, and diggin’ up mud bugs, there are also more than 160,000 oil and gas wells nestled along the area’s extensive network of swamps and bayous. Last summer, I drove along state route 82, often passing crews of plump, pink-necked workers – nearly all wearing the obligatory brimmed white hardhats and orange safety reflector vests mandated by OSHA – clustered around the works of small oil wells. In 2009, according to the Louisiana Oil and Gas Association, oil and gas revenues accounted for about $1.1 billion of Louisana’s economy, and the industry employed more than 1.8 million people. Oil and gas development also led to largescale wetland dredging, which turned it into a Swiss cheese patchwork of land and water that has accelerated erosion.

The central part of the United States functions much like a giant funnel, draining water from as far west as the Continental Divide and as far east as the Appalachian Mountains into the Mississippi River, through tributary rivers such as the Missouri and the Ohio. The largest river system in North America and the fourth longest river in the world, the Mighty Mississippi crosses more than 2,300 miles on its trip from lake-strewn Minnesota to the Gulf of Mexico. As it enters Lousisiana’s lush low country, it widens, meanders, and appears to slow down. Appearances can be deceiving, though, because there’s a lot of water — 600,000 cubic feet per second — moving through the river into the vast, marshy delta spreading into the Gulf’s saline waters.

Two men fish from a pirogue in Louisiana's marshland. 2008, photo by Louisiana Angler via WikiCommons

But the way today’s Mississippi River looks and functions is as much a product of man’s intervention as it is the hand of mother nature. Human engineering, while good for the economy in the short term, also has a lot to do with why Louisiana’s Gulf Coast is disappearing. Southern Louisiana is, by nature, an alluvial floodplain, which means that sediment from all over the Great Plains, carried downstream by spring floods, created the fan of spongy marshland protruding into the Gulf. Before anyone had the idea to build levees to prevent floods, straighten channels to aid navigation, and cut hundreds of oil and gas transport canals through the region’s wetlands, the Mississippi River would flood, spread silt and sediment over the surrounding land, and change its course arbitrarily. Today, the land around the river is actually sinking. In many places, the straitjacketed waterway is higher in elevation than the surrounding landscape — a feature that has proven disastrous whenever a levee fails.

Although last year’s Deep Horizon spill is still very much alive in the national dialog, it’s only one of the many problems that needing attention in America’s swampy underbelly. Louisiana continues to erode and sink while the sediment with which nature would have replenished it shoots out into the Gulf, burying and killing distant coral reefs. Land sinks more as oil reserves are pumped to nothing. Nutrients and fertilizers from agricultural Middle America, channeled into a river that functions as the country’s drainage ditch, bypass wetlands that might otherwise filter them, causing further harm to the Gulf and Caribbean ecosystems. The Atchafalaya continues to widen and scour, putting more and more stress on the flimsy control structure built to keep the river flowing toward Baton Rouge and New Orleans. By speeding up the river to speed up commerce and development, we have also driven the demise of a rich fishery and agricultural resource.

Perhaps our fast-paced lives are a good indication of what’s wrong. Perhaps we should slow down, and like the river, take a few extra turns here and there and look at how nature has done things for eons to see how we might do things now. I hope that years from now, I’ll still be able to drive along Southern Louisiana’s coast and see what I’ve seen before: long, flat sandy roadways flanked by trees dripping with Spanish moss and stilted trailers and French Colonial bungalows glistening beneath the summer sun’s relentless glare. I also hope to see the continuation of a culture — the rough Cajun French squawked by boat operators and construction crews, the Babineaux’s and Thibodeaux’s and Toup’s who lend their family names to towns and businesses — that was shaped by hundreds of years spent in concert with the deliberate pace of life dictated by America’s biggest wetland.

Erosion threatens places like the Sabine National Wildlife Refuge, a vast marsh in Louisiana's southwest corner. 2010, photo by Benjamin Preston

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3 Responses to “Southern Louisiana’s Vanishing Act”

  1. Raj says:

    It is sad that mankind is responsible for its destruction. A beautiful place is going to be in ruins in a few years time because of our greed. The damage has been done but people living there must act fast to prevent a disaster.

  2. It is sad that mankind is responsible for its destruction. A beautiful place is going to be in ruins in a few years time because of our greed. The damage has been done but people living there must act fast to prevent a disaster.
    +1

  3. [...] low country (where a surfeit of drilling operations has led to intense, precipitously catastrophic erosion) — has turned once-pristine lasndscapes into a swiss cheese of industrial development. Even [...]

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