THIBODAUX — Work will likely begin this year on a long-distance pipeline designed to carry sediment from the Mississippi River to restore wetlands east of Lafourche Parish.
The parish’s contribution to the pipeline was a point of contention for some Lafourche politicians. Local Levee District Directors said the project is an illustration of how some marsh creation can be done locally in the future.
The project consists of a corridor and pipeline that will bring sediment from the nutrient-rich Mississippi River over the levee, under roads and bayous before spewing it out along its corridor to the Barataria Waterway.
Spreading enough of this sediment strategically creates marsh in open water and bolsters surrounding wetlands threatened by lapping waves.
The project will go out for bids in March, project manager Kenneth Bahlinger said. Construction should begin this year, he said.
The pipeline was originally intended to carry sediment to build wetlands in Jefferson and Plaquemines parishes and south of Lafourche’s Delta Farm area. But rising costs halted the plans in Plaquemines.
Lafourche contributed $1 million in coastal restoration money to the project after a confrontational debate. Some local councilmen felt the money would be better spent on a project that is guaranteed to reach Lafourche Parish.
Bahlinger said the intent is still to bring it to Lafourche via the corridor left after the original pipeline is dismantled.
“You have to have something to put the pipe on,” Bahlinger said.
Parish President Charlotte Randolph previously described the $1 million contribution as an investment.
The pipeline combines two projects to carry 8 million cubic yards of sediment to create about 550 acres of marsh, according to Bahlinger.
Bahlinger declined to give an estimate for the total project with requests for bids to go out soon, but state officials late last year estimated the cost at around $60 million.
The state has lost 1,880 square miles of land to subsidence and erosion in the past 100 years. Reversing that trend is a focus of the state’s coastal master plan. That plan identifies $50 billion in potential restoration and protection projects to be implemented across the next 50 years.
The master plan, which is largely unfunded, identifies about $18 billion in marsh restoration projects over the next 50 years. The bulk of the projects use pipelines for sediment delivery.
Lafourche and Terrebonne sit in a particularly difficult spot for wetland restoration because of the area’s relatively long distance from major sources of renewable sediment in the Atchafalaya and Mississippi rivers, according to Terrebonne Levee Director Reggie Dupre.
The master plan also includes several river diversion projects that can’t reasonably apply to Terrebonne and Lafourche because of the lay of the land, Dupre said.
The individual levee districts have their own marsh creation projects as part of federally required mitigation for flood protection projects in wetlands.
The South Lafourche Levee District has completed a handful of marsh-creation projects outside the levee system in Lafourche.
“We try to take a natural approach and keep costs down as low as possible,” said Windell Curole, the district’s director.
Curole said careful choice of location to reduce wave action is important. He also said doing away with some of the more technical aspects of marsh creation like containment banks and carrying material from afar can drive down the cost of creating wetlands locally.
Just over the western levee in Golden Meadow, about 130 acres of marsh sit at the toe of the levee. Curole said that particular project was scheduled to create 50 acres but created more because the area was in broken marsh protected from wave action.
Curole said sediment dredged from smaller, closer waterways is useful for mitigation and small restoration jobs, but every marsh-creation site has different considerations.
“We just have to be smart with ever project,” Curole said. “You can’t apply the same standard to each project.”
Though it may be cheaper, state officials see using local sediment as “robbing Peter to pay Paul” and inadequate for larger-scale projects.
“In the long run, it is obvious that the long-term solution is massive, and that is getting massive amounts of sediment in the area,” said Chuck Perrodin, spokesman for the Coastal Protection and Restoration Authority. “We are looking to reach (the area), whether it is with pipelines. We are looking at a number of different means right now.”
Dupre said the whole-solution includes both local and river sediment.
“In my opinion, for local and smaller projects, although the material on the inner lakes might not be as good a quality, the price is such that it is worth considering,” Dupre said.
Dupre noted Terrebonne Parish has discussed building a sediment pipeline from the Atchafalaya River into Terrebonne Parish’s starving wetlands. That project is far from getting started, but some money has been allocated to it.
Dupre said the distance required by such a pipeline means it likely won’t be a solution for the entire parish.
“There is only so far you can get with these,” Dupre said. “In Terrebonne, the furthest you are going to get is the Houma Navigational Canal. That is still going to be very difficult.”
Because of this, the district must focus more on outright protection measures, Dupre said.
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