Closing the Barn Door in New Orleans

At a cost of $14.5 billion, the system the Corps of Engineers designed to protect New Orleans from hurricanes is finally in place. Of course, Hurricane Katrina was what they call a 400-year event, that is, the city will have such a storm only once every 400 years. So in all likelihood the new flood gates will mostly rust. Meanwhile, all of southern Louisiana is eroding into the Gulf at the rate of about 30 square miles a year, because the walled-in Mississippi no longer spreads its flood waters across those wetlands to refurbish them with silt. Unless something is done to reroute the Mississippi's floods, New Orleans will be a lonely island in the ocean before its flood gates are ever tested.