Friday, June 8, 2007

Flood Protection: Where we stand

At the last Tulane Engineering Forum, Dr. John Lopez gave this presentation on our current level of protection. He concentrated on what HAS been done, instead of what has been AUTHORIZED to do.

Keep in mind, this was presented to more than 100 engineers from all sorts of companies all over Southeast Louisiana. He spoke in between Thomas Jackson, the highly respected head of the Eastern Regional Levee Board, and 2 bigwigs from the Corps. This isn't a "fluff" presentation meant for the sheeple (just wanted an excuse to use that word).

Dr. Lopez used this graphic to visually represent the states of the various protection layers of the city:

Above the line represents improvement. Below the line is deterioration. The line is equal to pre-Katrina levels. The graphic at the bottom represents the various lines.

Here are his results:

Take a long look at that graphic. That's what's protecting this city. Did the Corps representatives raise any objections to the presentation? No, they applauded.

Next time someone says we're "better than we were pre-Katrina," remember that graphic.


Leigh C. said...

Oy vey!

Ya wanna hope that they were applauding the simplicity of the graphic...but that's waaay too much to hope for.

Tim said...

Hmmm. I agree with the general assessment that while parts of our protection system are improved, there remain weaknesses. So what when a storm surge comes, what good will miles of new, strong levees and walls be if there are still substantial low spots and weak points? Water will find its way in!

However, I must question the metric for evaluating the pros and cons in the protection system. For instance, it may be true that as much as 70% of the Chandeleur Islands are lost, but what is their contribution to the hurricane protection of the greater New Orleans area? I have seen modeling that suggests those islands are just too far way, that although they help knock down some waves, there is plenty of room for the wind to whip up he waves again on the way to the levees east of New Orleans and St. Bernard.

And again, the real contribution of marsh and other minor features is only for small hurricanes, like Cindy. They are nothing more than bugs on the windshield of for events on the scale of Hurricane Katrina.