Hurricane Katrina so weakened New Orleans' 350-mile levee system that it probably can't protect the city from flooding even in a relatively minor storm, officials with the Army Corps of Engineers said.
While workers have closed most of the breaches that allowed the city to flood after Katrina, none of the burst levees has been returned to its pre-flood height, corps officials said. Many other sections of the levee have washed away or have eroded enough that even a small rise in the surrounding waters would spill into the city.
The damage to the levees is particularly worrisome as Hurricane Rita approaches the Gulf Coast. Engineers were working feverishly Tuesday to close gaps.
One break remains open on the 17th Street Canal and two are still open along the London Avenue canals, spokeswoman Dana Finney said. Corps engineers dropped 80 10,000-pound sandbags into the breaches Tuesday in an effort to close them.
Walls along both canals are so damaged, however, that corps officials decided to prepare to seal the canals' entrances to Lake Pontchartrain temporarily—even though such a move would render them useless in carrying out their designated purpose, draining water from the city into the lake. A decision on whether to take the final steps to close the canals will be made at noon Wednesday.
"London Avenue has got significant structural problems, we know that," said Col. Richard P. Wagenaar, the corps's New Orleans district commander. "That's why we're closing it off."
Corps officials said recovery efforts were likely to be delayed in St. Bernard and Plaquemines parishes by a decision to close levee breaks there that had been made to help drain those areas. St. Bernard Parish has been pumped nearly dry.
Computer modeling suggests that parts of the city and nearby parishes could be endangered even without a direct hit from Rita, Finney said.
In a statement Sunday, Brig Gen. Robert Crear, the commander of the corps's Katrina recovery task force, said the system in its current state "does not ensure that the city will be protected against storms or hurricanes." He warned that people in the city would be at risk.
Tuesday, Crear said he thought the levees might be able to handle a storm surge of up to 5 feet, far less than the 17 feet that Katrina brought. He said there was no way the levee system could be repaired before Rita hits and that the goal was to make repairs in time for next year's hurricane season, which begins June 1.
Any new flooding probably would slow down repair operations, said David Pezza, a corps engineering-construction specialist. "I have to say we would have to anticipate a delay," Pezza said, "but our goals are still June 2006."
Officials have noted that new flooding would primarily threaten areas that already were damaged in the floods from Katrina.
In its statement Sunday, corps officials offered a grim assessment of the levee system: Only one of six levees cited was deemed in good shape; the others were likely to flood in a storm.
Joseph Suhayada, retired director of the Louisiana Water Resources Research Institute at Louisiana State University, said some breaches had been filled only to 3 or 4 feet above the level of Lake Pontchartrain, although they were still being built up. They might reach 5 feet of protection soon, "which is not much of a storm."
The corps has stocked 800 huge sandbags to close any new levee breaches and has ordered 2,500 more.
Even heavy rain would be a threat. "With anywhere from 2 to 3 inches of rain, we will get some locations that could have potentially 2 to 3 feet of water," Wagenaar said.
Wagenaar said New Orleans' pumping system, which moves rainwater out of the below-sea-level city, was operating at 40 to 50 percent of capacity. One pump station, at the northwest corner of the city's Ninth Ward, is a total loss, and Finney said about 75 of New Orleans' 174 pumps were still out of commission.
The Catch-22: If canals are closed to protect against a storm surge, rainwater can't be pumped through them out of the city until they're reopened.
"Hopefully, there won't be too much rain," Wagenaar said.
(Carey, of the San Jose Mercury News, reported from San Jose, Calif. Knight Ridder Newspapers correspondent Nicholas Spangler of The Miami Herald contributed to this report from New Orleans.)
(c) 2005, Knight Ridder/Tribune Information Services.
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