A tiny sliver of land provides natural defense against hurricanes

On the Rigolets, at the Orleans-St. Tammany Parish line, Fort Pike takes visitors back in time.

Art Schick, who works at the state historic site, notes the irony of the name.

"Rigolets means 'little ditch,'" said Schick, who points out that description no longer applies to the small body of water that the fort was built on in 1828.

As land eroded, the Rigolets expanded and swallowed part of the moat that once surrounded the fort.

Schick said, at the time of construction, "there was probably a good 200 feet of land" between the fort and the waterway.

Schick points to crumbling walls on the fort, as coastal erosion accelerates the inevitable effects of time. The historic fort stands as one of the most prominent features on the Orleans Landbridge, a sliver of real estate hugging Highway 90 from Chef Pass toward the Pearl River.

"That landbridge moderates, reduces the amount of storm surge that comes into Lake Pontchartrain," said Dr. John Lopez, a coastal scientist and director of the Lake Pontchartrain Basin Foundation.

Without steps to protect it, scientists fear the same forces chewing away at the rest of coastal Louisiana could doom the landbridge.

"The landbridge may not survive if there's no marsh on the other side," said Cheryl Kelly, a resident of the Venetian Isles neighborhood near Chef Pass.

Lopez said engineering studies have found that the landbridge knocks down 2 feet of storm surge on the north shore of Lake Pontchartrain, another foot on the south shore, and reduces salt concentrations in Hammond and other areas far to the west.

"The cypress trees in those marshes, they're going to start looking like the (dead) trees in Chalmette when they opened up the Mississippi River Gulf Outlet."

Lopez notes the state coastal master plan includes several large projects to protect the landbridge, some of which have already been completed.

The plan envisions $43 million in shoreline protection measures to reduce wave action by 2031, encompassing approximately 27,000 feet of coastal marsh on the east side the landbridge. The first phase of the master plan also includes $473 million, aimed at creating 8,510 acres of marsh through dredging operations by 2031.

Depending on funding, even more ambitious marsh creation projects could be implemented after 2032.

Lopez is confident the state can save the landbridge, "as long as we keep that progression of projects."

Partly due to pressure from politicians and residents, the master plan included the loose concept of a levee, or some other storm surge barrier, running from the Rigolets to Chef Pass. Supporters argue such a levee would produce benefits from Slidell to Ascension Parish.

"All of this whole area encompassing the Lake Pontchartrain basin is going to be saved along with New Orleans," said Dean Marullo, a Venetian Isles resident.

However, the idea draws howls of protest from politicians and residents in Mississippi, who fear a barrier would drive water their way.

"Everything you build in the way of structural protection is going to move risk onto someone else," said Mark Davis, Director of the Tulane Institute on Water Resources Law and Policy.

Kelly would like to see a more cooperative effort with Mississippi.

"Come together at the table and let's find solutions for both places," Kelly said.

Supporters argue, through a few thousand years of history, Mississippi took storm surge deflected from Louisiana.

Even today, water piles up in the natural "V" shape of the Louisiana coast from Plaquemines Parish to the Mississippi Sound. In one sense, a levee would restore the effects of land that no longer exists.

However, engineers with the Corps have cautioned that even the levee wouldn't be a cure-all.

In shallow Lake Pontchartrain, they reason, surge blocked by a barrier would have plenty of time to kick up again before plowing into LaPlace and other communities on the western side of the lake.

Davis believes the levee would be a hard sell in Congress, already faced with a backlog of billions of dollars in water projects awaiting funding.

"You've got major metropolitan areas, with millions and millions of people, that are going to be needing infrastructure investment, Davis said.

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