Sunday, August 31, 2008

New Orleans asks: Will the rebuilt levees hold?

road on the levee
Originally uploaded by Ale*
Students asked about this issue last week in class.

NEW ORLEANS (AP) — Just three years after Hurricane Katrina, New Orleans confronts a new threat from Gustav and a stark question: Will the partially rebuilt levees hold?

levee and drain pipes
Despite $2 billion in improvements, including 220 miles of repaired, raised and replaced floodwalls, 17 new pump stations and more flood-resistant pump stations, nobody can say for sure the city won't be swamped again. And if it is, could it ever recover?

"It's scary, man," said Robert Russell, a 63-year-old plumber whose house in Gentilly Woods is close to floodwalls on the Industrial Canal that are so suspect the Army Corps of Engineers is buffering them with large baskets filled with sand.

"They say it's not up to code," he said. "We'll have to wait and see."

Levee experts and the Army Corps insist New Orleans is safer than before Katrina flooded more than 80 percent of the city on Aug. 29, 2005.

Yet the system still has severe shortcomings: Flood barriers meant only to withstand medium-strength storms, hidden layers of weak soil and navigation channels that inadvertently funnel storm surge into the city, to name a few.

"The positive thing about having any storm hit you, it will reveal any kind of frailty in the system," said J. David Rogers, an engineer at Missouri University of Science and Technology, who's tracked the construction closely. "And we shouldn't be surprised if there is frailty."

Experts estimate the system is only a third of the way to where the corps wants it by 2011 — strong enough to protect against what scientists call a 100-year-storm. That type of hurricane has a 1 percent chance of occurring each year.

By comparison, the corps says Katrina was a 396-year storm, a rare catastrophic hurricane. The agency has not classified Gustav, which was crossing Jamaica Thursday.

"We're not close to 100-year-level protection yet," said Robert Turner, the regional director of the Southeast Louisiana Flood Protection Authority-East. "It's not worth putting your life at risk if you have the means to get out."

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