As Hurricane Gustav bore down Sunday on New Orleans, top officials at the Army Corps of Engineers said that despite repairs and reinforcements, the 350-mile levee system still might not be able to fully protect the city.
The earth and concrete levees are stronger and higher than when Hurricane Katrina struck three years ago, but they would still be unable to resist a storm of the same size.
"It all depends on the strength of the storm, in terms of wind speed, water surge and how fast the hurricane tracks," Maj. Gen. Don T. Riley, deputy chief of the corps, said in an interview. "There are still vulnerabilities. There are gaps in the system."
If Gustav hits the city with a large surge, the levees could be too low to prevent flooding, particularly in Gentilly, St. Bernard Parish and the 9th Ward, all neighborhoods that were partially or completely flooded three years ago.
After Katrina, the corps made emergency repairs to about 150 miles of damaged or destroyed levees and upgraded about 70 more miles of levees.
In addition, Congress has authorized programs totaling almost $15 billion to upgrade the entire system by 2011. But that project is only 25% complete.
Federal officials say Gustav has the potential to inflict serious damage, and must be taken seriously. As of Sunday evening, the National Hurricane Center said the storm was "extremely dangerous" and would produce a 10- to 14-foot surge of water, down from an earlier prediction of 15 to 25 feet.
Like Katrina, Gustav has a large diameter and is aiming at the Louisiana coast. It appeared Sunday that the storm was tracking to the west of New Orleans, where it would exert the greatest pressure on the low-lying communities to the south of downtown New Orleans. This area west of the Mississippi River, known to locals as the West Bank, escaped devastating flood damage three years ago. The Army Corps' levee rebuilding program is less complete in this area than in others.
After Katrina, the corps was harshly criticized by experts who said it had repeatedly miscalculated the strength of its levees and was bungling the repairs. Some of the greatest failures involved concrete storm walls lining drainage canals used to pump water from areas of the city below sea level.
Rather than rebuild miles of suspect storm walls, the corps built barrier gates at the mouths of drainage canals at Lake Pontchartrain and installed massive pumps to move flood water from the canals into the lake. The quality and testing of the pumps grew into a major scandal, but corps officials say the system is now fully tested and ready for action.
