Posted on October 5, 2022
After nearly 40 years, a final decision on the state’s $2.2 billion bid to reconnect the Mississippi River to the sediment-starved marshes on Plaquemines Parish’s east bank is closer than ever.
This week marked the release of two major, lengthy reports detailing the environmental impact of a proposal to construct a two-mile-long channel near Ironton that would divert Mississippi River water — as well as the land-building sand and mud suspended within it — into Barataria Bay.
If approved, the Mid-Barataria Sediment Diversion would be the first of its kind. The engineered design attempts to mimic how the river built Louisiana over thousands of years before it was tamed by levees in the last century. It’s a key piece in the state’s 50-year, $50 billion plan to rebuild and maintain some of Louisiana’s lower third in the face of a coastal land loss crisis and increasing impacts of global sea level rise.
“We’re ecstatic,” said Bren Haase, executive director of the Coastal Protection and Restoration Authority. “We’re not at the finish line yet. It’s been said we’re at about the two-yard line.”
In its final environmental impact statement, the U.S. Army Corps of Engineers responded to about 40,000 public comments and outlined the project’s benefits and consequences. That robust analysis will determine whether the federal agency delivers its final permit decision in December.
Last Wednesday, the federal and state trustees, who will decide whether to fund the project, released their final report indicating plans to move forward with paying for the Mid-Barataria Sediment Diversion with settlement money from the 2010 BP oil spill.
The land built and sustained by the large-scale diversion over the next 50 years outweighed the tradeoffs, wrote the Louisiana Trustee Implementation Group.
“The Trustees believe that a sediment diversion is the only way to achieve a self-sustaining marsh ecosystem in the Barataria Basin,” the trustees wrote.
What exactly will the diversion do, and what’s happened to get it to this point? Here’s what you need to know about where the project has been and where it’s headed.
What is the Mid-Barataria Sediment Diversion?
Where the Mississippi River could once spill over its banks freely, it’s now bound by tall levees. Those structures have curtailed some of the destructive flooding seen in the past, but imprisoning the river has also led to the rapid degradation of land in southeast Louisiana — land that also provides much-needed protection from hurricanes.
The Mid-Barataria Sediment Diversion aims to reverse some of wetland loss seen in the rapidly degrading Barataria Basin. Bound by Bayou Lafourche and the Mississippi River, the basin has lost more than 430 square miles of what was once almost 1,500 square miles of land since 1932.
Once operating, the sediment diversion would build up to 27 square miles, or 17,280 acres, by 2050, according to the Corps’ final environmental report. And by 2070, the basin would have nearly 20% more wetlands than it would if the project doesn’t move forward.
“It changes the fundamental situation that’s causing much of the loss within the basin right now,” Haase said.
That’s because the diversion would direct up to 75,000 cubic feet of Mississippi River water per second into the basin, partially restoring that historic connection between the river and the neighboring wetlands that have now been converted to open water. A concrete channel would guide the water through a gated structure that will control how much is let in. That amount will depend on the flow of the river itself, waxing and waning with flood season.
Its location on the river will be key to its success, placed near Myrtle Grove after extensive research suggested the spot would be ideal for capturing mud and sand.
That much sediment-rich water will be a boon for building new land and maintaining other marsh created by the state with dredged material. But it will also send a shock to the brackish and saltwater system created by decades of land loss.
A swift change for fisheries, more money to help
Scoping out a spot for the Mid-Barataria diversion dates back to 1984, though it wasn’t until the early 2000s that a design began to take shape. For nearly two decades, Plaquemines’ oyster harvesters and shrimpers have been among the most vocal opponents. Both the final Corps and trustee reports confirm that the oysters and brown shrimp they catch for a living will see the steepest decline if the project comes online.
Experts have said the reintroduction of so much freshwater would immediately alter the area, forcing those who have spent a lifetime fishing to adapt.
George Ricks, a charter fisherman who has long rejected the project, said the expensive project won’t build enough land to justify the hit to Plaquemines’ seafood industry and local communities.
“The public should be outraged,” he said. “These projects are not going to save our coast.”
Haase said the state is well aware of the steep impact to those fisheries. Last spring, CPRA began drafting a $305 million plan to mitigate the project’s negative effects. After developing the plan over the past year through meetings with stakeholders, the final mitigation plan will put nearly $380 million toward lessening the harm as the bay transforms.
“Without a doubt, there’ll be impacts, particularly in the short term, because you’re changing things,” said Haase. “That’s why we are pursuing the mitigation measures that try to assist in the transition to those changes.”
The bulk of the mitigation money — $256 million — will go to six communities that sit outside the levees to elevate roads and docks where possible to stay above the rising tide, improve sewage, add floating gardens, raise homes and offer voluntary buyouts.
It also sets aside $60 million to address the expected harm to the bottlenose dolphins living in the bay, a population decimated by the BP spill. The Corps’ report noted that some studies suggest the opening of the diversion will lower survival rates and cause their eventual extinction. Too much freshwater can kill dolphins and lower their rate of reproductive success.
The $60 million will go toward tracking the population and enhance the state’s ability to respond to dolphins stranded on land or in fresher waters to try to increase the chance of survival.
The new plan allocates $54 million to fisheries to:
- Establish new public seed grounds for oysters
- Enhance oyster reefs
- Improve fishing vessels for shrimpers
- Help crabbers, fishers and shrimpers market their products
- Create workforce training opportunities for those who choose to enter a new field
Though the state increased the amount of money for fisheries by $20 million, Ricks argued it likely still isn’t enough to compensate for what will be long-lasting changes.
“That’s going to be a drop in the bucket,” he said.
A final decision in December
The two reports pave the way for permitting and funding decisions by the end of the year. Both the Army Corps and the Louisiana Trustees will issue them in December, and Haase said the state hasn’t received any indication that it won’t go their way.
If Mid-Barataria receives a green light, the five-year construction can start in early 2023. But that doesn’t mean the path forward will be clear.
Should the Corps grant the permit, diversion opponents who have spent the past year and a half building their case will likely sue the federal agency over the decision. Despite holding about 130 individual meetings in Plaquemines, CPRA hasn’t swayed the opinions of many of the fishers or residents who fear for the future of their jobs and homes if the project is built, said parish councilman Carlton LaFrance.
“They still don’t want it. They still believe it won’t work,” he said.
Ricks said several nonprofits are talking about lawsuits that could center on using money meant for repairing the harm caused by the oil spill to pay for a project that will hurt dolphins’ recovery from the 2010 disaster.
Congress issued Louisiana a waiver for the Marine Mammal Protection Act in 2018 that would allow the project to move forward despite the threat to dolphins. It still required the state to monitor and minimize impacts.
Haase said he wouldn’t be surprised if the Corps was challenged over approving the diversion.
“Hopefully, we have dotted our I’s, crossed our T’s, and done things the way we should have done them. And we believe we have,” Haase said.