The NY Times reports that the Corps has already instituted a number of significant changes and improvements to the levee system, which actually will begin functioning as a coordinated system for the first time in its history.
The sheer scale of the nearly $15 billion project, which is not due to be completed until the beginning of next year’s hurricane season, brings to mind an earlier American age when the nation built huge works like the Brooklyn Bridge, the Hoover Dam and the Interstate highway system.That definitely seems like a significant improvement, but the Army Corps' own website information suggests a subtly different picture.
While New Orleans’s bulwark is still almost a year away from full strength, the city’s reinforced defenses are already stronger than they were before Katrina. Even so, experts argue, that the city’s defenses after 2011 will still provide less protection than it needs to avoid serious flooding in massive storms.
For a region devastated by a storm and by a loss of faith in the government’s ability to safeguard it, the new system is a test of more than the prowess of the Army Corps of Engineers. Some residents say they may never fully get over the failure in Katrina. “Do I trust them?” asked Beverly Crais, a Jefferson Parish resident. “No. How can I trust somebody who makes that big of an error?”
That could be part of the reason that the top of the Lake Borgne wall is crenelated like the fortifications of a castle. The indentations, the engineers say, will weaken waves that splash against the top. But it will also send a clear visual message to anyone who sees it: there is safety behind this wall.
The patchwork of walls and levees that fell apart after Katrina were, in the words of the corps’ own report on the disaster, “a system in name only.” But projects like the wall — vast but largely unseen, because they take the first line of defense away from the center of New Orleans — are knitted into a single barrier.
“It’s a comprehensive-system approach,” said Karen Durham-Aguilera, a civilian engineer responsible for work on what is now known as the Hurricane and Storm Damage Risk Reduction System. “We’re not even in the same universe any more.”
The lessons of Katrina were learned at a tremendous cost in life and property, but they can be seen throughout the works.
Where some of the old levees were built with dredged mud and shell fill that washed away in the storm, the new earthworks are toughened with clay. Many old floodwalls were shaped, in cross section, like the letter I and stood on muddy soil that seemed almost eager to give way; most of the new work is sturdier, shaped like an inverted T and braced with pilings driven diagonally into the ground. The corps is strengthening some soil, by mixing cement deep into the ground.
In fact, the Corps' own map suggests that significant stretches of levees South of the city are not quite up to the standards put in place to defend against a 100-year storm.
New Orleans may still hope that this hurricane season is a quiet one, so that the city can be in a much better position to handle a significant storm once the flood control systems are upgraded.
The fifth anniversary of Hurricane Katrina is August 29.