|For novel ideas about building embedded systems (both hardware and firmware), join the 27,000+ engineers who subscribe to The Embedded Muse, a free biweekly newsletter. The Muse has no hype, no vendor PR. It takes just a few seconds (just enter your email, which is shared with absolutely no one) to subscribe.|
By Jack Ganssle
For the Want of a Nail
With a 300-foot section of an earth-and-concrete levee on New Orleans' 17th Street Canal gushing water into Jefferson Parish yesterday authorities called on a higher power.
While the politicians stand behind rows of microphones and survey conditions from the safety of the air, a small group of engineers are valiantly trying to fix a 300 foot wide breach in the levee. It appears there's no standard way to plug such a huge failure, and the engineers are trying old methods and inventing new ones.
According to the New York Times (http://nytimes.com/2005/08/31/national/nationalspecial/31levee.html) 22 pumps distributed around the city normally run at nearly full capacity all the time to keep this sunken city from flooding. All the time. Just Katrina's rain would have overwhelmed these machines. Certainly a 300 foot levee failure is far too much for that handful of already-stressed pumps.
It's hard to find much information about the cost of New Orleans' hurricane protection system, but http://www.house.gov/jefferson/old-020920/jfrpt_transportation.htm suggests that a handful of millions were needed to maintain and enhance the levees and pumps. It appears these are federal funds, as usual; surely Jefferson is spinning in his grave at about 5000 radians per second.
Surely, though, a city dependant on pumps for its very survival, which on a good day uses essentially all available pumping capacity, lives on the very precipice of existence. Surely engineers must have been screaming for more capacity. And just as surely those demands were lost in the orgy of infighting that passes for politics today.
It's easy to argue that building a city below sea level is a Bad Idea. But no one has ever - till this week - seriously suggested abandoning New Orleans. Given the decision to continue battling entropy, one would hope there'd be margin in the system.
Strong storms are reputedly rare. The New Orleans levee project's web site is down, but a mirror at http://web.archive.org/web/20040923120837/http://orleanslevee.com/ claims hurricanes will come within 80 miles of the city as follows:
- Category 1 Storm once every 8 years
- Category 2 Storm once every 19 years
- Category 3 Storm once every 32 years
- Category 4 Storm once every 70 years
- Category 5 Storm once every 180 years
Yet Cat 5 Camille roared ashore just a few miles east in 1969. Ivan, a strong Category 4, barely missed last year. And Katrina has now destroyed the place. Maybe these numbers need revision.
A prescient paper (http://www.colorado.edu/hazards/o/nov04/nov04c.html) wonders what would have happened if Ivan had made landfall in the Big Easy, and concludes rebuilding could cost up to $100 billion. That number happily appears very high, but the surely many billions will be required.
I can't help but be amazed that, as usual, there's plenty of time and money to do the job right the second time. The parallel to engineering organizations is uncanny. Too often we rush an incomplete and frankly unacceptable product to market, only to later issue an expensive recall and initiate an even more expensive redesign.
I do wonder if the international community will pour out aid as we did for the tsunami last year.
Meanwhile, visit https://www.redcross.org/donate/donation-form.asp to send aid.
Thanks to the many readers who inquired about my son, who just started college there a week ago. He escaped with just a backpack. Presumably the carload of stuff we brought to his dorm room is watery rubbish, but stuff can be replaced.