How strong are the levees?
Perhaps the most important part of the defense system — and consequently the most scrutinized — is the levee system, which failed under the intensity and relentless pounding of Katrina. The levees, which were designed to withstand a Category 3 storm such as Katrina, failed in two ways, experts said. Initially, floodwaters came over the top of the levees. Then, as pressure built up on the levee walls during Katrina’s torrents, they gave way at the bottom, leading to the catastrophic flooding of the city. “It was the holes that killed us,” said Bob Bea, a civil and environmental engineering professor at the University of California at Berkley. The Army Corps of Engineers is addressing the most vulnerable parts of the levee system, making the levees higher in some areas and adding fortification in the areas that were breached. However, those fortifications only mean that they will be able to protect against a fast-moving Category 3 storm. Anything stronger — perhaps even another storm
