Coastal-restoration projects approved in St. Tammany, Terrebonne parishes

CWPRRA should begin work to begin in 2014.

Nearly $23 million will be spent on a project to restore several hundred acres of marsh around Terrebonne Parish's Lost Lake. Work on the coastal restoration plan is expected to begin next year.

In late January, the Coastal Wetlands, Planning, Protection and Restoration Act Task Force, better known as CWPPRA, approved construction of marsh-building projects in both the Bayou Bonfouca area in St. Tammany Parish and Terrebonne Parish’s Lost Lake.

The projects are sponsored by the U.S. Fish & Wildlife Service in conjunction with the state. CWPPRA projects are funded by the federal government with a 15-percent funding match coming from Louisiana.

In the case of Bayou Bonfouca, the total estimated cost to repair wetlands at the bayou’s mouth is $23.8 million. The goal is to create and nourish 533 acres of marsh in the southeastern part of St. Tammany, and to nourish 42 acres of low-salinity brackish marsh in open water next to Bayou Bonfouca.

The marsh there was fairly stable before 2005’s Hurricane Katrina, but it now has numerous breaches that are allowing saltwater intrusion to ravage still-fertile marshes behind the first lines of defense.

Those gaps also create tidal movement in the marsh, which causes deeper waters and vexes the natural estuarine system for much of the aquatic wildlife found in Lake Pontchartrain.

The project at Bonfouca would ultimately result in an approximately 424-net-acre benefit of intermediate marsh over a 20-year span, according to a CWPPRA fact sheet on the build-up.

Robert Dubois, federal project manager for the Bayou Bonfouca project, said he estimates the project will begin next March.

Dubois said the reason it cannot begin sooner is that the area is critical habitat for Gulf sturgeon, so dredging is disallowed outside of a May-to-September window.

“We’ll have to punt the ball and wait until next year to get ready,” he said. “We should go to bid in December or January, and we’ll build the containment dikes first. As soon as we can start the dredging, we will.

“This way, it gives us plenty of time to get ready to go. It’s a pretty large project, and we don’t have a lot of time to get it done. We have to be ready.”

Dubois admitted the work is a small portion of what is needed to stop the inexorable march inland of the Louisiana coastline.

“In the overall scheme of the coast, (the Bonfouca project) is a fraction, a pinpoint project,” he said. “But it’s an area of need. There are some very large gaps in there, especially east of Bonfouca (toward south Slidell.) So we’re fulfilling the idea of getting it back to what it was before.

“That marsh is critical nursery for the lake (and critical to protect human habitat, as well.)”

The Lost Lake project area will cover 7,312 acres at estimated cost of $22.9 million. Approximately 465 acres of marsh will be created, with a net benefit after 20 years expected to be 452 acres.

According to the CWPRAA fact sheet, significant marsh loss “has occurred between Lake Pagie and Bayou DeCade to the point that little structural framework remains separating” the two bodies of water. Northeast of Lost Lake, significant ponding has occurred, and “wind/wave energy continues to result in marsh loss.”

West of the lake, “interior breakup has occurred as a result of ponding and the periodic entrapment of higher-salinity waters during storm events.”

The marsh-creation project is expected to restore and protect key elements of the lake’s structural framework, including lake rim and bayou bank.

Construction is expected to begin on the Lost Lake marsh build in early 2014.

In addition to the Bonfouca and Lost Lake builds, CWPPRA approved additional work at four other locations at their Jan. 24 meeting. They project locations and cost are:

• North Catfish Lake marsh creation (Lafourche Parish) — $3,216,194

• Terracing and marsh creation south of Big Mar (Plaquemines Parish) — $2,308,599

• Bayou Dupont sediment delivery (marsh creation in Jefferson and Plaquemines parishes) — $3,415,930

• Cameron Meadows marsh creation and terracing (Cameron Parish) —  $3,108,025.

More information on all of these projects can be found  at www.lacoast.gov.