NEW ORLEANS -- Nearly 600 people who died because of Hurricane Katrina might have survived had floodwalls on two New Orleans canals not collapsed, a Knight Ridder analysis of where bodies were found after the storm indicates.
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 -- probably because of poor design, shoddy construction or improper maintenance -- 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 is still being debated. 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.
"A big yes," Van Heerden replied to an e-mail question asking whether the majority of the city would have stayed largely dry had those floodwalls held.
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 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.
Said Robert Bea, a professor of civil and environmental engineering at the University of California at Berkeley, "Had we not lost the integrity at 17th Street and the integrity on London, we would have had water in there and maybe some soggy carpets, but certainly not the water level that ultimately led to the catastrophe. That is directly attributable to those two sets of failures."
Bea is a member of a team of engineers who studied the levee system under the auspices of the National Science Foundation.
Experts still are 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 still are 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.
"We feel we may have lost people to the river," he said. "We feel we may have lost people into the marshes. We feel we may have lost people into the Gulf" of Mexico.
Of the bodies that have been recovered, only 565 have been released to families for burial. Of those, 422, or about 75 percent, were from New Orleans, and 104, or about 18 percent, from St. Bernard Parish.
Officials have given the identities only of victims whose bodies have been released.
The Louisiana Department of Health and Hospitals, in response to a request from Knight Ridder, earlier this month released a list 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.
They showed that far more deaths were reported at hospitals and nursing homes in western areas of the city -- 171, or 79 percent -- than in the eastern portions -- 45, or 21 percent.
The number of dead recovered outside health institutions, primarily from private homes, also was higher in west and central New Orleans than in the east; 354, or 59.5 percent, were retrieved in the west, compared with 241, or 40.5 percent, in the east.
Another 63 bodies were recovered at two mass collection points in west and central New Orleans, where people had deposited them for retrieval by authorities.