Map graphic from CPRA

Louisiana’s Coastal Protection and Restoration Authority has a complex plan for reconnecting the Mississippi River with coastal regions that have steadily disappeared under Gulf waters. They have a detailed timeline for the effort, stretching over several years, and right now they have a huge amount of money to throw at these efforts.

But they still have to win over a skeptical part of the public in south Louisiana, particularly in coastal communities where commercial fishing could be impacted by the projects. And ultimately it still won’t be enough to completely reclaim the state’s lost territory.

Part of the campaign to win over the skeptics is a series of public meetings, called “Coastal Connections.” The latest occurred at the Braithwaite Auditorium in Plaquemines Parish Wednesday afternoon.

These events are designed to put CPRA project leaders and engineers face to face with residents and businesses who may be impacted by two massive river diversion projects, the Mid-Barataria and Mid-Breton Sediment Diversions.

CPRA’s Coastal Connections event at the Braithwaite Auditorium Wednesday, , Feb. 6 Credit: Tom Wright / The Lens

“We’ve gotten a lot of feedback through other projects, other processes through CPRA that we’re not down in the communities enough.” said Brad Barth, CPRA’s diversion project manager. “With Coastal Connections, we really wanted to be down here on a regular basis, having conversations with the community on things that are going on at CPRA.”

The two diversion projects are designed to address an old problem. In the 1930s, when Americans began to build levees along the Mississippi River, the ages-old process of river water depositing sediment along the banks was interrupted. That process was what built much of Louisiana’s land in the first place.

Subsidence, rising sea levels and saltwater intrusion in the decades to come have all contributed to one of the highest land loss rates in the world. The Barataria and Breton basins and the Mississippi River Delta downriver have lost about 700 square miles since those first levees were built, a large part of the almost 2,000 square miles lost across the state.

The loss of that much coastal land means less protection against storm surge from Gulf weather and less land for building and sustaining communities.

“Our main objectives for the projects are reconnecting that natural process that’s been broken in the river,” Barth said, “reconnect the river to the basins and the bays to get that sediment and that fresh water and the nutrients back out into the marshes that have been cut off from those processes for multiple years.”

CPRA essentially wants to create two channels from the river — one on the west bank of the river, one on the east bank — in Plaquemines Parish. The agency estimates those diversions will deliver between 2-3 million cubic yards of river sediment annually to Barataria Bay and Breton Sound, respectively.

Map graphic from CPRA

As that sediment accumulates over the years, land-based vegetation will accumulate again in those areas. “With more green stuff in between [the Gulf and the land], we all know that should help knock down storm surge,” Barth said. “It should reduce wave impacts, as well.”

Barth said the Mid-Barataria diversion is outlooked for construction in at least two years.

“We have a ways to go through the environmental review process,” he told us. “Right now, it’s probably mid to late year of 2021, per schedule. But we’ll always keep a close eye on that schedule, depending on how long it takes to put the environmental review documentation together.”

Once the federally-required environmental impact statement is complete, a public comment period also is required before permitting and finally construction can begin.

“It’s going to be devastating for a lot of people in Jefferson and St Bernard, and Plaquemines. It’s going to wipe out our industry.”—Acy Cooper, Louisiana Shrimp Association

There’s been no delay in comments, though, from critics of the diversion effort, including members of the fishing industry.

“I live on the mouth of the river and we deal with the river every year,” said Acy Cooper, a professional fisherman and president of the Louisiana Shrimp Association. “We know what it’s like. If the river comes up early, we have to move off, and Barataria Bay is one of the places we move to. And when they start putting this fresh water diversion in, that’s not an option anymore. It’s going to be devastating for a lot of people in Jefferson and St Bernard, and Plaquemines. It’s going to wipe out our industry.”

Cooper said he’d rather see the CPRA keep a focus on dredging operations, in which sediment is removed directly from the river bottom and placed where it’s needed.

“Dredging, you can target where you want to put it,” Cooper said. “The diversions are more experimental. We have a couple of diversions that we have on the lower end of the parish now — it’s really not sediment diversions, it’s fresh water diversions.”

Cooper said the influx of fresh water will ruin the estuaries, where the river meets the Gulf and where he and his fellow commercial fishermen often work.

Among the informational materials provided at the Coastal Connections meeting was a “FAQ” document that listed frequent criticisms raised by the diversion opponents followed by point-by-point rebuttals from the CPRA.

Barth said dredging remains a major part of the state’s Coastal Master Plan, first published in 2012 and revised in 2017.

“Our bread and butter of our program … is dredge projects,” Barth told The Lens. “Probably 80 percent of our marsh creation budget in the 2017 Coastal Master Plan is for dredging projects alone. Sediment diversions are a very, very small portion of that budget. We will continue to dredge and dredge as much as possible.”

But Barth said there’s a dramatic difference in how much new land is produced from dredging and how much is produced from river diversions.

“We talk dredging projects, we’re talking thousands of acres,” he said. “When we talk diversions and the potential power and the magnitude of the river, it’s tens of thousands of acres.”

The diversion and dredging projects are all part of the sweeping Coastal Master Plan, which Barth said includes “140 different projects across the entire Louisiana coast [and] a $50 billion plan, split equally between restoration and protection.”

He acknowledges that completing these projects will require significant amounts of long-term funding. And the agency has only identified a portion of the funding needed.

The Mid-Basin Sediment Diversion Program — which includes both the Mid-Barataria and the Mid-Breton projects — is covered by about $2 billion in money from the state’s settlement with BP after the 2010 Deepwater Horizon disaster. Barth noted that much of that funding will be spent locally, over the course of a three- to five-year construction schedule.

As steep as the cost is for implementing the Coastal Master Plan, the costs for not implementing it could be worse, according to the CPRA. Barth said that cost is estimated at over $300 million a year in damages in Plaquemines Parish alone.

“What we see with coastal land loss is going to be directly tied a lot to that sea level rise and subsidence rate that we see,” he said. “And as you know, scientists maybe have difference of opinions of whether it’s this rate or that rate, how high or low. So, when we look at that, we try to look at both ends of the spectrum and hope for the best scenario, but plan for the worst.”

“We have to be very clear about what we can realistically expect. We’re not going to be able to do more than maintaining small portions of the coast.”—Torbjörn Törnqvist, Tulane University

A recent report by Tulane University researchers Molly Keogh and Torbjörn Törnqvist raised new concerns about how the rate of sea level rise is measured, in Louisiana and low-lying coastal regions around the world. Their research found that traditional measurements using tide gauges may underestimate the rate by not taking subsidence under the water into account.

“With the new information we have now, we have a stronger foundation to estimate rates of relative sea level rise,” Törnqvist said in a Tuesday interview with The Lens. “And when I say relative sea level rise, that’s basically the sum of the subsidence that occurs along the coast plus the sea level rise that happens because of climate change. We’ve definitely made a step forward in better being able to pin down some numbers.”

The 2017 Master Coastal Plan does not account for the heightened rate of sea level rise that Törnqvist describes. But Törnqvist remains a strong proponent of the plan’s diversion program.

“I believe that it’s the only viable method to maintain small portions of the Louisiana coast,” Törnqvist said. “And we have to be very clear about what we can realistically expect. We’re not going to be able to do more than maintaining small portions of the coast.”

This screen capture from CPRA’s interactive map shows projected land loss over 50 years, under its medium severity scenario without CMP measures. Click for the interactive.

The researcher says he has made the point for years that, without addressing greenhouse gas emissions that have led to our warming planet and rising seas, even the most complex of coastal restoration plans will do little good in the long run.

“If we don’t reduce emissions and greenhouse gases continue to rise, then we’re going to more and more move toward some very dangerous territory where you could look at massive, widespread collapse of ice sheets,” Törnqvist warns. “If those types of things start to happen, then at some point you have to ask yourself, why are we actually worried about coastal restoration and river diversions? That suddenly will become small potatoes.

“But that’s not where we are, I believe,” he stressed. “And I think these diversions, they should happen.”

Cooper with the La. Shrimp Association doesn’t dispute the risks of rising seas.

“There’s not a fisherman down there in Plaquemines Parish who doesn’t want coastal restoration,” he said. “We know we need it. But we need it the right way. We can do this without sacrificing the fishing industry.”

CPRA’s Coastal Connections event at the Braithwaite Auditorium Wednesday, Feb. 6 Credit: Tom Wright / The Lens

Barth and other CPRA representatives fielded plenty of questions from fishermen and other residents concerned about the impacts of the Mid-Barataria and Mid-Breton diversions.

“Whether you’re a fisherman or with us at the state, with the CPRA, or a homeowner or somebody with the oil & gas industry, down here in the area of Plaquemines or St. Bernard — we can all look out the window and know that our coast is changing,” the program director said. “We’re losing land at a rapid rate. And we need to do something. Everyone can agree upon that.”

But agreeing on what should be done, he acknowledges, is a different story.