Louisiana’s coast is starved for sediment, but its largest swamp has too much of it

BAYOU SORREL, LA. (WVUE) - The Atchafalaya Basin covers roughly one million acres of swamps, bayous, lakes, and bottomland hardwoods, an area larger than the Florida Everglades.

If the Everglades is, as author Marjory Stoneman Douglas famously wrote, a “river of grass,” the Atchafalaya is a river of trees.

America’s largest river swamp, the Atchafalaya is the largest area in Louisiana still gaining land.

The basin begins near Simmesport, Louisiana. and stretches 140 miles to the south, transitioning to coastal marsh before it reaches the Gulf coast.

“What else makes this thing so special is the culture, the people, the time that you spend here, almost like your Papaw to your daddy to you and your kids, in the same places, doing the same things,” said Cliff Crochet, a professional bass fisherman from Pierre Part.

The basin hosts more than 400 species, including the country’s largest wild crawfish population and the fishermen who catch them.

“When you drive a boat out here, it’s like being in a wilderness. There’s times you might not see another person all day,” he said.

The organization’s Director of Conservation, Seth Blitch, said while growing up in Florida, he had never heard of the Atchafalaya Basin.

“I think it’s the most impressive place that one knows about,” said Blitch said.

Over the last couple of centuries, man has heavily engineered and altered the basin.

By law, the U.S. Army Corps of Engineers sends 30 percent of the combined flow of the Mississippi and Red Rivers down the Atchalaya.

The Old River Control Structure, a series of giant floodgates, regulates the flow of water and prevents the Mississippi from changing course.

“What once was a big, beautiful, bold, awesome place is still all that, but it’s dying,” Crochet said. “It’s almost a shell of what it once was.”

Over a century ago, loggers and later oil companies, dug canals in the basin.

Spill banks along the canals, effectively levees, interrupt the natural north-south flow of water.

Over the decades, as the basin’s hydrology changed, river sediment has silted in parts of the swamp and its bayous.

On a boat ride through the basin, Chris Macaluso points to sandbars along Little Bayou Pigeon.

Macaluso, Director of the Mississippi River Program for the Theodore Roosevelt Conservation Partnership, noted the willow trees along the banks of bayous which often block the view of cypress.

Macaluso steers his boat past Big Bayou Pigeon, which he says was 10 times as wide when he was a child.

“It’s silted in so badly, you can’t navigate it anymore,” Macaluso said.

While it may seem far remote from New Orleans, the basin plays a critical role in the city’s flood protection.

When the Mississippi River rises beyond the capacity of the Bonnet Carré Spillway, the Corps can rely on its other giant relief value, the Morganza Spillway, which sends water into the basin.

“If you’re in New Orleans, even if you don’t come to the basin, it matters in your life because you’re connected to it in some way,” Seth Blitch said.

Spill banks also prevent water from flowing out of the swamp, leading to stagnant water which lowers oxygen levels and creates small dead zones for fish.

“The water in here gets hot, and if it doesn’t move right, all the oxygen comes out of that water and it becomes a place where fish and crawfish can’t live anymore,” Macaluso said.

There is a growing consensus among groups fighting for the basin that the Corps of Engineers should change how it manages the rivers.

At times, that could involve sending less water down the Atchafalaya, at other times more.

“Are there times of the year to get a pulse of more water and times of the year could we pull back and help let the swamp drain? Maybe the water’s been high and it really needs to drain and dry out that back swamp,” Piazza said.

One proposed solution, designed to promote water flow and quality, has sparked controversy.

The East Grand Lake Project would cut a dozen openings in the banks of waterways with the aim of restoring the more natural north-south flow of water. At the southern end of the project area, it would also shave the tops off canal banks, allowing the water to drain.

“Make little small gaps to where we can reconnect some of these historical bayous that took water back through the swamp,” Piazza said, who argues the project would be a step toward restoring the more natural hydrology of the swamp.

“When these areas get this river water, the trees grow 20% faster. We know that the crawfish populations are better,” he said.

The project sparked controversy and drew a lawsuit from a coalition of environmental groups, including the Atchafalaya Basinkeeper, a group dedicated to restoring the swamp and its waterways.

The sand is the problem," said Dean Wilson, founder of the Atchafalaya Basinkeeper. “You cannot pass the sand through the wetlands,” Wilson said.

The Nature Conservancy argued the cuts would be shallow, enough to keep out the kinds of heavy sands which sink to the bottom.

“Just shutting everything down is just not the answer,” Piazza said. “It’s not the answer in the coast and it’s not the answer in the Atchafalaya Basin because these systems are river floodplain systems. You can’t keep the river out of river floodplain systems.”

Earlier this year, a federal judge rescinded a Corps permit for the project, marking a victory for the the groups suing to stop it.

Judge Brian A. Jackson of the U.S. District Court for the Middle District of Louisiana ruled March 31 that had failed to consider all of the factors when it awarded a permit, effectively halting the project for now.

Wilson argues for a wide use of sediment traps, long holes dug in the floor of a waterway to allow sediment to accumulate. The silt could be recycled back into the channel, Wilson argues, or mined and delivered by pipeline to the sediment-starved coast.

“We’re losing the coast and we have too much sand in the basin,” Wilson said. “Actually, the amount of sediment and sand we need to protect our coast, that’s the only place you’re going to get is in the Atchafalaya Basin.”

Others believe cost could be a significant obstacle to such long-distance sediment pipelines.

“If we do come in here and do some large-scale dredging projects to reopen some of these lakes and these bayous, there’s not a good answer, in a cost-effective way, as to what you do with that silt,” Macaluso said.

Wilson said the group wants Congress to declare a state of emergency to fund a management plan similar to the one it proposes.

“Every year, it’s getting worse. What we’re trying to do is get Congress to declare a state of emergency so that can do the funding to put a management plan similar to what we propose,” Wilson said.

Advocates on all sides agree on the need to reverse course.

“We need to get off this kind of culture of stagnation and get a culture of restoration in this basin,” Piazza said.

Despite costs and the many other obstacles, Cliff Crochet strikes an optimistic tone.

“We can move mountains, and I’m pretty sure with the right people involved, the right hearts involved, Louisiana will be just fine,” Crochet said.

Here are more interesting facts about the Atchafalaya Basin from the Atchafalaya National Heritage Area:

• It is larger than the Florida Everglades.
• It’s five times more productive than any other river basin in North America.
• About 65 species of reptiles and amphibians inhabit the Basin.
• Over 250 known species of birds fly in the Basin.
• Other species of animals found in the area include black bear, nutria, fox, muskrat, beaver, otter and raccoon.
• The Basin is home to the largest nesting concentration of bald eagles in the south central United States.
• There are more than 100 different species of fish and aquatic life in the Basin.
• The Basin has an estimated average annual commercial harvest of nearly 22 million pounds of crawfish.
• The Basin contains the largest contiguous bottomland hardwood forest in North America and is the largest overflow alluvial hardwood swamp in the United States.

Subscribe to the Fox 8 YouTube channel.