Experts reviewing Hurricane Katrina's catastrophic damage to New Orleans last August say the storm actually had four deadly flooding elements.
Hassan Mashriqui, a researcher with the Louisiana State University Hurricane Center, told The New York Times the storm moved northeast with winds exceeding 125 mph, bringing with it a 17-foot storm surge into landfall at the town of Buras where levees were built to withstand a 13-foot surge.
As the eye passed over Lake Borgne, it created an 18-foot surge that St. Bernard Parish's 13-foot levees couldn't contain.
The third hit came when the storm forcefully shot water into the city's Inner Harbor Navigation Canal, said Mashriqui. Those are the waters that obliterated the Lower Ninth ward, the Times said.
As the storm pushed eastward into Mississippi, it sent a final less powerful surge toward New Orleans across Lake Pontchartrain, north of the city, which forced lake water into the center of the city, the study said.
Copyright 2006 by United Press International
Explore further: Sea change: What took decades to destroy in oceans took millennia to recover