New Orleans – A $3 million experiment by the Army Corps of Engineers this week will simulate the conditions that caused some of the levee failures that led to Hurricane Katrina’s disastrous flooding.
In the test, the corps will gradually pump water into a section of the London Avenue Canal, one of the canals whose flood walls toppled during the storm two years ago, leading to most of the flooding that ravaged the main part of the city.
Engineers will monitor the amount of seepage beneath the flood wall and how much the structure tilts – measures that will tell them how much rising water the wall can withstand. The corps promises to carefully monitor the experiment to ensure that the test does not itself cause a new breach.
“Some computations show the wall is going to fail at certain water levels; some show it won’t,” said Ray Martin, a geotechnical engineer consulting with the corps on the project. “This experiment will let us know.”
The fact that such an experiment is necessary reflects the uncertainty that continues to surround the question of exactly what caused the city’s flood defenses to fail. Experts say that answering these questions is critical to efforts to protect New Orleans from future hurricanes.
Despite three investigations, disputes continue over a host of key questions: What exactly was the primary cause behind the toppling of the canal walls? Would deeper wall supports, which, to save money, were built shorter than originally designed, have held the walls upright? Did earthen levees fail mainly because surging waters overtopped them, or did they crumble first because of flimsy materials? Did a major man-made shipping channel known as the Mississippi River Gulf Outlet allow the storm surge to slam the city?
Equally as important – and, perhaps more important to the thousands who are suing the corps – is the question of whether government agencies and contractors who built the levees and flood walls are guilty of negligence or wrongdoing.
“The bottom line is that this city was destroyed, and the public doesn’t yet have an undisputed explanation,” said Sandy Rosenthal, director of , a local advocacy group. “There are a lot of questions that have yet to be answered.”
has been agitating for improved flood defenses and urging politicians to establish an “8/29 commission,” a congressional body modeled after the Sept. 11 commission.
“There have been numerous studies … without any clear direction of how to prevent a flood- control-system failure in the future,” said Sen. Mary Landrieu, D-La.
