The flooded streets of New Orleans pose an entirely new problem for public works directors. What infrastructure challenges will they find once the water has receded? Photo: Getty Images

Life is a risky business. Every moment of every day brings some level of risk. When we design a building or a water treatment plant or a levee, we accept and try to define the risk. We know that there will be situations where the stresses on the system will exceed the design, so we build in safety factors that we hope will control the unknowns. This is a difficult concept for the public to accept: you mean to tell me you knew this could happen and did nothing to stop it?

How do we explain that everything is a gamble? Or that we simply can't afford to design for the worst conceivable circumstances? No one designs buildings to resist a crash by a fully fueled airliner. And no one designs a city to withstand a Category 5 hurricane. With unlimited funds we probably could, but then there would be other unforeseeable circumstances.

The bigger question, though, may be whether Hurricane Katrina was really a natural phenomenon so severe that it overwhelmed the design of the system, or were the odds simply not in the Gulf Coast or New Orleans' favor? Was enough money allocated over the years to lower the risk to an acceptable level, or did inadequate funding finally catch up with an under-designed system? Although there's not a one-to-one relationship between dollars spent and risk reduction, it is very expensive to keep water out of a coastal city that's below sea level.

Some kids are said to be "at risk," meaning that their lives are so unstable they could easily end up as dropouts or drug addicts. We try to give those kids some extra help to prevent them from drifting into antisocial behavior. Some cities are similarly at-risk and should get some extra help. New Orleans was obviously one of those cities, and its citizens would seem to have accepted that. Most, however, if they thought about it at all, probably thought the risk was somehow being managed—that the levees would hold, that the pumps would keep up. After all, the reasoning goes, New Orleans has been here for 300 years—we can survive anything.

Well, almost anything. Now we are faced with the nation's worst-ever infrastructure breakdown and guess who's going to take the blame? Once the politicians tire of pointing fingers at one another for the bungled emergency response, they will be looking for another scapegoat. No one will understand how the engineers charged with safeguarding the city could have been so "irresponsible" as to let this happen. It won't be pretty. But perhaps this presents an opportunity to finally get the message across: if we continue to gamble by shortchanging our infrastructure, inevitably the bill comes due.

Bill Palmer
Editor in Chief