Floodwall failure linked to about 600 deaths

Engineers say these victims' New Orleans neighborhoods would have stayed mainly dry if not for problems on two city canals

December 30, 2005|By JOHN SIMERMAN, DWIGHT OTT AND TED MELLNIK | JOHN SIMERMAN, DWIGHT OTT AND TED MELLNIK,KNIGHT RIDDER NEWSPAPERS.

NEW ORLEANS -- Nearly 600 people who died because of Hurricane Katrina might have survived had floodwalls on two New Orleans canals not collapsed, according to a Knight Ridder analysis of where bodies were found after the storm.

The bodies of at least 588 people were recovered in neighborhoods that engineers say would have remained largely dry had the walls of the 17th Street and London Avenue canals not given way after the height of the storm.

In contrast, 286 bodies were recovered in the Lower Ninth Ward, New Orleans East and neighboring St. Bernard Parish, where Katrina's storm surge poured over levees and flooded neighborhoods.

The role of the 17th Street and London Avenue canal floodwalls in the destruction of New Orleans has been hotly debated in the four months since the storm. Engineers who are investigating their collapse think that floodwaters generated by Katrina never rose high enough to pour over the walls, and they blame flawed design, construction or maintenance for the walls' failure and the flooding that followed.

Louisiana authorities are investigating whether laws were broken during construction of the floodwalls, but until now there's been no attempt to quantify how much their failure may have contributed to New Orleans' death toll.

Louisiana State University hurricane expert Ivor Van Heerden said there was no doubt that vast areas of the city would have remained dry, and residents relatively unscathed, had the walls of the 17th Street and London Avenue canals not collapsed.

Asked in an e-mail whether the majority of the city would have stayed largely dry had those floodwalls held, Van Heerden replied: "A big yes."

Peter Nicholson, an associate professor of civil and environmental engineering at the University of Hawaii, said some flooding in central New Orleans came from breaches on the west side of the Industrial Canal, but that those breaches were above sea level and the flooding stopped as Katrina's surge died down Aug. 29.

"The big difference is with 17th Street and London the breaches opened gaps that were below sea level and continued to drain Lake Pontchartrain until they were closed," Nicholson said.

This confounded rescue efforts and left thousands stranded in darkened hospitals, attics, on freeway overpasses or in the foul refuges of the Superdome and the convention center.

Dr. Frank Minyard, the Orleans Parish coroner, has estimated that 20 percent of Katrina's victims drowned. Scores more died awaiting rescue, trapped by floodwaters. The causes of death for many will never be known because their bodies were too badly decomposed by the time they were recovered.

Months after Katrina's landfall, experts are still debating how the tragedy might have been avoided. Local officials ordered an evacuation of New Orleans, but perhaps not soon enough. Tens of thousands of residents ignored the evacuation order. Federal help came slowly.

Debate also continues over what part Louisiana's fractured system for governing the levees played in the flooding. In addition to the two canals whose floodwalls collapsed, engineers reported poor maintenance and construction practices at scores of places throughout the vast levee system.

Louisiana officials are still tabulating the death toll, which stands at nearly 1,100 statewide. Dr. Louis Cataldie, the state medical examiner, said a precise total might never be known.

The Louisiana Department of Health and Hospitals, in response to a request from Knight Ridder, released a list this month of nearly 600 locations where at least 874 bodies had been recovered in Orleans and St. Bernard parishes, the two areas in Louisiana that Katrina hit the hardest.

Louisiana health officials say the list is incomplete, and a review of the data showed some inaccuracies.

But the addresses provided the first comprehensive view of where Katrina's New Orleans victims were found and allowed a systematic look at the dead for the first time.

The addresses showed that far more dead were recovered in western and central New Orleans than in the city's eastern neighborhoods, even though the Lower Ninth Ward, New Orleans East and St. Bernard Parish received the storm's harshest battering.

Van Heerden, the LSU hurricane expert, said the flooding in the eastern areas began shortly before the storm made landfall at 6:10 a.m. - an 18-foot storm surge from Lake Borgne destroyed much of the earthen levee system that had protected St. Bernard Parish. Most of the parish's 123 victims drowned in their homes, said Dr. Bryan Bertucci, the parish coroner.

By 6:30 a.m., water as high as 17 feet surged into a convergence of two channels east of New Orleans, engineers believe. It overwhelmed the levees, added to the flooding in St. Bernard Parish and began to flood the Lower Ninth Ward.

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