The sense of just how much the world had changed for the Army Corps of Engineers struck Daniel Hitchings in a tense conference call last month. Mr. Hitchings, director of the hurricane response task force for the Corps of Engineers, was on a call with representatives of the Federal Emergency Management Agency and the National Flood Insurance Program. He explained that the levees and floodwalls around New Orleans, both existing and new, had been designed to be tall enough to hold back storm surges, but would allow about two feet of a six-foot wave to splash over the top.
The representatives from the insurance program were stunned. Water splashing over the top would violate the requirements of the federal flood insurance program, they said, though the corps has been designing levees that way for decades. It was an impasse. One federal agency's rules had come face to face with those of another, and the emergency officials were not pleased. "We were frustrated, angry and disappointed with the news we got from the corps," said a senior administration official who was granted anonymity to avoid straining relations between the agencies.
Those differing perceptions of flood control help explain why Donald E. Powell, federal coordinator for Gulf Coast rebuilding, announced on Thursday that the levees in the New Orleans region that were being rebuilt would not meet the insurance standard of protecting against a 100-year flood, the category that has a 1 percent chance of occurring in any given year. The announcement was in many ways a candid admission that the old ways of building flood protection no longer applied.
Mr. Powell insisted that the $3.4 billion in work currently under way would make the levee system stronger than ever and prevent catastrophic failure in another storm of Hurricane Katrina's strength. But he said work to bring the levees up to the standard required by the insurance agency would require as much as $6 billion in additional spending to raise levee heights, replace suspect floodwalls and take other corrective action. If FEMA cannot certify the flood-stopping power of the levees, the agency's maps will have to treat them as if they are not there. In other words, as if the land behind them is unprotected. That will have a significant effect on how neighborhoods will be rebuilt, how high off the ground homes will have to be constructed and the cost of insurance.
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http://www.nytimes.com/2006/04/01/us/nationalspecial/01levees.html?_r=1&pagewanted=all&oref=slogin