Ceilidh

Michael Zey
futurist3000@aol.com

By WOODROW WILKINS JR. - Delta Democrat Times

GREENVILLE - One result of the Great Flood of 1927 was that the federal government upgraded the mainline Mississippi River levees, improving protection in New Orleans and the Mississippi Delta.

However, the massive flooding that crippled New Orleans after Hurricane Katrina struck has brought attention to the inadequacy of the floodwalls that stood between the city and Lake Ponchartrain.

The structural weakness was known, and plans were drawn up to create a barrier that would withstand a Category 5 hurricane. Katrina was a Category 4 storm when its winds and rain reached the Mississippi and Louisiana Gulf Coast. However, government officials have said the floodwalls were built to withstand only a Category 3 storm, and the barrier project was never funded.

Peter Nimrod, chief engineer for the Mississippi Levee Board in Greenville, said the barrier plan was derailed by a lawsuit over environmental concerns.



"Back in 1965, after Hurricane Betsy, they realized they were subject to hurricane flooding from Lake Ponchartrain," Nimrod said on Tuesday. "They designed the hurricane protection levees, which were not built.

"At the same time, environmental groups got involved and sued.

"It got tied up in litigation during the '70s, and what came out of this was it was kicked back to Category 3 protection.

"Failure was imminent."






The barrier project

After Betsy, a Category 2 hurricane when it hit the Louisiana coast, the U.S. Army Corps of Engineers designed and began clearing sites for the so-called Lake Ponchartrain Hurricane Barrier Project, the Los Angeles Times reported earlier this month. It required miles of levees and two massive storm gates that would close off two passages where storm surges would barrel into the lake.

Similar gates protect the Netherlands from North Sea surges.

The project was approved by Congress and signed by President Johnson. However, in 1977, a federal judge issued an injunction to stop it, saying the Corps of Engineers' environmental impact statement failed to satisfy federal environmental laws.

Among those opposing the project were the environmental group Save Our Wetlands, fishermen and St. Tammany Parish.

Officials in the parish, just north of Lake Ponchartrain, hoped to see a large shipyard built on a bayou, the L.A. Times said. The shipyard was never built, and the area is now under water.

Opponents of the barrier said the control measures would sharply reduce the flow of salt water into Lake Ponchartrain, damaging shellfish and other aquatic life. They also feared the barrier would drain the wetlands, leaving it "extremely susceptible to hurricane tidal surges."

In 1985, the Corps abandoned the project. Congress later authorized the floodwalls that are now in place.

During Hurricane Katrina, Lake Ponchartrain - swollen by 12 feet - was slammed by 135 mph winds against the floodwalls. The barriers failed in five places, flooding New Orleans.

Politics of protection

Nimrod said he doesn't think it was a funding issue.

"They calculated benefit-to-cost ratios for different designs," he said. "They calculated based on existing structures and what it would take to rebuild them.

"Politicians directed the Corps to build Category 3 protection.

"They kind of found a compromise there, I believe, which was unfortunate."

Dr. Nasim Uddin, a wind damage mitigation expert at the University of Alabama at Birmingham, said there was a lack of understanding between the policy makers and the engineers.

"It's not that what happened, we did not know," he said. "We knew the problem, and we knew how to solve it. But we didn't argue strongly enough for the policy makers to take care of the issue.

"There was some complacency, but I am not sure at what level."

Construction matters

Uddin also noted that in some areas wrecked by Katrina, older buildings remain standing where newer structures were either destroyed or severely damaged.

"It depends on the construction materials," he said. "Masonry, brick, especially the ones that were built in the earlier times, they are really sturdy and can do better in regard to at least the flooding and maybe the wind."

Wooden structures are more like to blow away, Uddin said.

"One of the issues we have been struggling with for a long time is really convincing people to spend $2,000 to $4,000 and put some fixtures, details that can really save your house big time," he said. "It's not gonna be 100 percent proof, but it will help."

Clips, brackets, steel plates with jointing and other fixtures can be used to strengthen a house against strong winds, Uddin said.

"Improved building materials have the potential to reduce life and property losses, which will continue to increase if steps are not taken to make coastal communities less vulnerable," he said.

Meanwhile, Nimrod said the levees protecting the Delta are in excellent shape.

"What we got here is a levee that we can't allow to fail," he said. "We feel good that if we have a project-design flood in the next year, we feel like we can flood fight."

Over the years, engineers discovered that the height of the mainline levee was too low in a 69-mile stretch extending southward from Washington County. An ongoing project is raising the levees' height in those areas, with many sections already completed.

"We're not in their position," Nimrod said of New Orleans, "and we don't want to be in their position."