Environment
6:41 am
Tue August 26, 2014

River Diversions And The Fate Of Louisiana's Coast

The Wax Lake Delta, created by a diversion of the Atchafalaya River.
The Wax Lake Delta, created by a diversion of the Atchafalaya River.
Credit Jesse Hardman / WWNO

A big part of Louisiana’s coastal Master Plan centers around something called “diversions.” Fresh water from the Mississippi River is diverted so that the water, and the silt it carries, can rebuild the sinking coast. But this technique, a centerpiece of Louisiana's coastal Master Plan, is contentious.

Those who have been lucky enough to travel to the Wax Lake Delta are prone to gush about it. “You’re going a place that is one of the few bright spots on the coast of Louisiana,” says Ben Weber, who leads trips to the Wax Lake area as an outreach coordinator for the National Wildlife Federation.

From the stern of a fishing boat, Weber enjoys a view of water lilies and marsh grasses. “It’s one of the only places in our country where rivers are actually building land, and still have that process in tact of delivering sediment and water to the marshes, the lifeblood of all these wetlands that we depend on.”

The Nature Conservancy's Ben Weber, out on the Wax Lake Delta.
The Nature Conservancy's Ben Weber, out on the Wax Lake Delta.
Credit Jesse Hardman / WWNO

From above one can see how the lush, green Delta has grown and spread into the Gulf over decades. It’s a bit of an outlier. Most people in this region have been their coastal land retreat due to sea level rise and saltwater intrusion.

The reason Wax Lake delta is growing — not eroding — is a 1941 intervention by the Army Corps of Engineers in the Atchafalaya River basin. To reduce the threat of flooding in Morgan City, it made a channel to let the river water flow into the gulf. This created a marsh, the Wax Lake Delta. A bit of a happy accident.

Dr. John Lopez is the director of the Lake Pontchartrain Basin Foundation. He says that by-product of river diversion is now a save-the-coast strategy.

"The intent of the diversions has shifted more toward trying to deliver sediment and helping maintain or rebuild wetlands in today’s coastal system," he says.

With Wax Lake as Exhibit A, the Coastal Restoration and Protection Authority views diversions as the best chance for restoring lost wetlands. There are ten diversions in the current Master Plan. “It’s a win-win," says Ivy St. Romain, owner of Ivy's Tackle Box in Morgan City. He guides his charter boat through Wax Lake and points out his favorite spots to catch fish and waterfowl.

Marsh being created in the Wax Lake Delta.
Marsh being created in the Wax Lake Delta.
Credit Jesse Hardman / WWNO

St. Romain wants his outdoor brethren in Plaquemines and St. Bernard Parishes to fish and hunt in healthy wetlands, too. He thinks diversions are the answer. "If they’ve got erosion going on right now, and there’s a diversion put in, and it doesn’t do — which it will, but if it doesn’t do — what they say, they’re not losing anything, they already got land being washed away. But if it does, look what they can expect. They can expect something like this, beautiful build up.”

But there’s another sermon about diversions out there. Bethlehem Baptist church is in Braithwaite, a small town on the east side of the Mississippi River in Plaquemines Parish.

Tonight the local preacher turns 40 members of his congregation over to George Ricks, a charter-fishing captain in St. Bernard Parish.

Ricks started a non-profit, the Save Louisiana Coalition a little over a year ago. His organization is tied closely to Louisiana’s commercial fishing and seafood industry. They oppose the parts of the Coastal Restoration and Protection Authorities that advocate for Wax Lake style diversions. "If you put the amount of fresh water in these large scale river diversions that they want to put in, its gonna turn the estuary totally fresh, and that's totally unacceptable," says Ricks.

Captain George Ricks of the Save Louisiana Coalition.
Captain George Ricks of the Save Louisiana Coalition.
Credit Jesse Hardman / WWNO

He says letting the river flow free will wipe out the saltwater marshes that fish and oysters love. "If they put what they want to put in with these things, they'll be no more fishing industry in St. Bernard's and Plaquemines. Simple as that."

Captain Ricks also says natural diversions take too long, and the land created is easily destroyed by storms. He does support rebuilding the coast. He just thinks dredging sediment is more efficient. Pile truckloads of mud where you need it, then you don't have to wait for the river.

Plaquemines Parish president Billy Nungesser agrees. He wants to build land, and quick, to create a coastal buffer against storms. And keep encroaching salt water at bay. "We believe that the berms, ridges and isles, pumping the river sediment, give us protection today," he says. "Not only for the people, but it protects those critical habitats."

But dredging is extremely expensive. And, unnatural. Dr. Paul Kemp at LSU is in the louder chorus supporting diversions. “It's an existential thing really," says Kemp.

He says Wax Lake is a powerful example of a river system’s ability to heal itself. "We've been working on this for a long time, and we haven't come up with a better way to do it, better than what nature figured out billions of years ago." Let the Mississippi to do what it was meant to do, he says: move sediment south and create land.

Save Louisiana Coalition.
Save Louisiana Coalition.
Credit Jesse Hardman / WWNO

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