A look at Louisiana's restored barrier islands, the state's largest coastal project to date
Just in time for another above-average hurricane season, state officials on Thursday got to view for the first time the completed and restored Terrebonne Basin Barrier Islands, aimed at protecting residents from storms rolling in from the Gulf of Mexico.
Coastal Protection and Restoration Authority executive director Bren Haase, Pontchartrain Conservancy executive director Kristi Trail and media took a seaplane flight over to see the completed project, which was finished in June.
Down below the seaplane, Haase and Trail saw the Trinity-East and Timbalier islands with its sand dunes, vegetation and sand fences. The restoration used more than 8.8 million cubic yards of dredged sediment from Ship Shoal, a sand formation about 15 miles south.
Located off the coast of Terrebonne and Lafourche parishes, the completed Terrebonne Basin Barrier Island and Beach Nourishment project restored 1,080 acres of barrier island habitat and 8.6 miles of beach. It is the largest project the CPRA has completed to date.
The sand is enough to fill the Superdome more than twice. It cost $166 million and was paid for by fines collected from the Deepwater Horizon oil spill, plus $3 million in state funds. It restored 261 acres on Trinity-East Island, 252 acres on Timbalier Island and 567 acres on West Belle Headland.
“It really puts into perspective the scale of the projects we’re doing,” Haase said.
The project to restore the barrier islands began in the summer of 2019 and has faced direct hits from Hurricane Zeta in 2020 and Hurricane Ida in 2021. Haase said that Trinity-East was completed before Hurricane Ida made landfall and held up well.
CPRA project manager April Newman said the natural vegetation helps contribute to longevity of the project, with sand grasses growing to keep the deposited sediment in place.
“With sand, just anything you can do to hold in place helps while an ecosystem develops,” Newman said. “A pile of said itself is not an ecosystem, it takes a little while for everything to settle into place. It’s definitely extending the lifetime of the island.”
She also emphasized the importance of integrating multiple lines of defense through coastal restoration and hurricane protection measures by utilizing both natural and man-made barriers.
Barrier islands are important because they are a physical demarcation between the Gulf of Mexico and the Louisiana coast. They act as the first line of defense and a buffer zone in protecting communities in Terrebonne and Lafourche.
These natural landscapes are another piece of risk reduction and help weaken an oncoming hurricane that would otherwise be able to gather more energy when traveling over an area of open water.
Lafourche Parish President Archie Chaisson joined in on celebrating the restoration project and its added protection for parish constituents in a statement.
“Projects like these represent continued protection for our residents and infrastructure that make our communities places people can still live, work and play,” Chaisson said. “ As we saw last hurricane season, these barrier islands are a vital link in the chain, and without them, the effects of the storm would probably have been much different in Lafourche.”
In a press release, Terrebonne Parish President Gordy Dove noted the importance of these barrier islands in protecting communities from storm surge.
“Without these crucial islands, mainland Terrebonne is at the mercy of hurricane and tropical event-induced storm surge and flooding,” Dove said. “In addition, these important islands play a crucial role in protecting our coastal marshes from destruction.”
Haase and the rest of CPRA hope that by continuing to supplement sand when needed, placing infrastructure like sand fences to reduce wind speeds and building dunes and vegetation, it will help the longevity of the restored barrier islands.
“These islands are not static. They're not where they aren't today, where they were 10 years ago, certainly not 50 years ago. They're gonna continue to move, they're gonna continue to migrate and change,” Haase said. “So we expect that. But our goal really is to try to not pin them in place, not lock them in their own place, but try to make sure that at least the landforms last as long as they possibly can.”