Government wrong on new Orleans flooding.

According to the Army Corps of Engineers, the broken levees that flooded the city of New Orleans failed when the storm surge overtopped the floodwalls and, spilling to their foundations, undermined their structural integrity. This explanation, which has gotten wide currency with popular programming on such cable channels as The Discovery Channel, now appears to be faulty.

According to this explanation, the levees were not designed to cope with a storm as powerful as Katrina. As it turns out, however, Katrina's storm surge was not as uniformly powerful as originally thought. Scientists and engineers at Louisiana State University's Hurricane Center have found that although some levees were topped, accounting for some of the flooding, several others were not. "We are absolutely convinced that those floodwalls were never overtopped," said Ivor van Heerden, who serves as deputy director of the center. In fact, according to the Washington Post, evidence indicates that the storm surge fell several feet short of overtopping the floodwalls along the city's 17th Street and London Avenue floodwalls. Breaches in these locations caused most of the flooding the city experienced. "This should not have been a big deal for these floodwalls," said G. Paul Kemp, an oceanographer and hurricane expert with Louisiana State University. "It should have been a modest challenge. There's no way this should have exceeded the capacity." In a related peculiarity, earthen floodwalls withstood the onslaught of the storm, while the concrete barriers did not. According to former Congressman Bob Livingston, the concrete barriers "shouldn't have broken."

So why did they break? Radical black nationalist Louis Farrakhan said they were deliberately destroyed so that rich whites could steal property from poor blacks. "I heard from a very reliable source who saw a 25 foot deep crater under the levee breach," Farrakhan alleged. "It may have been blown up to destroy the black part of town and keep the white part dry." There is, of course, no evidence of any such thing taking place. A simpler explanation is found in the ground underneath New Orleans and its levees. Due to continuous pumping to keep the city dry, even during normal days, the ground beneath the city has been sinking. This sinking, known as subsidence, has not only caused the levees themselves to sink, but has gradually weakened their foundations.

Another reason the levees failed was, essentially, poor engineering. For instance, in the early 1980s when a floodwall on the 17th Street Canal was being designed, probes found an unstable layer of peat about 15 feet below sea level. Despite this, the pilings that anchored the structure, according to a report in the New York Times on October 24, were anchored no deeper than 17 feet. The report stated: "Several outside engineers who have examined the designs say the decision not to hammer the pilings deeper ... left the support of the floodwall dangerously dependent on soil that could easily have washed out under the immense pressure from the floodwater."