One factor not taken into account in Una’s proposed solution: the Mississippi Delta (which shields New Orleans) is rapidly eroding, partly as a result of the levees already in place.
If we just keep building bigger levees, and if the delta continues to erode around the city, and if New Orleans continues to sink, aren’t we going to eventually wind up with a city in a hole out in the middle of the Gulf of Mexico?
I am continually amazed at what human engineering can accomplish, but I’m not sure we could hope to maintain such a city. Can even the strongest levee withstand a direct hit from a category 5 storm? --With (potentially) no delta to shield it? I’m not sure I share Una’s confidence on that point. Moving water is immensely powerful. Katrina, remember, just gave New Orleans a glancing blow from a category 4 storm.
I want to strongly second spoke-'s post. Last night I saw an interview with an editor of Scientific American (which ran an issue about the LA/MS delta situation a while back). He pointed out that the current rate of delta erosion makes NO a hole in the Gulf by the end of this century. The rate of erosion is of course accelerating.
It makes no sense to spend 10s of billions of dollars on a place that will be completely obliterated in a few decades no matter what we do.
This one issue alone kills the “well, you have to have a port there” argument. NO will no longer be on the river. It will be in the gulf.
Not only is Mother Nature a bitch, you aren’t going to win an argument with her.
Well, from reading this I got the impression that with every day that goes by, New Orleans and the surrounding coastline becomes more exposed as the swamp between it and the open gulf disappears. Whether this means that in 20 years or so a Category 3 will be able to hit NO as hard as a Category 4 does now, I have no idea.
Also, I believe the height of a storm surge is not necessarily related to the strength of a hurricane - Katrina may just have brought an unusually large amount of ocean along with it.
So far from the readings and postings, none of my original proposal would be a safe way to rebuild the city.
It sounds like the Levee system could be rebuilt, but without the rebuilding of the wetlands around New Orleans this would only be a partial or temporary repair.
Raising the city up could work but then eventually the city would become a sinking island and the bridges would still be increasingly susceptible to hurricane damage or destruction.
I think the wetlands refurbishment would have many benefits and should be investigated.
It may be worth abandoning some of the lower portions of the city accept as massive greenways. I think the city population will drop quite a bit for a while. Figure 200,000+ won’t come back.
We could rebuild strong levees to protect the city and then replenish the wetlands and start raising some of the lower sections. If done slowly it shouldn’t be crippling financially.
I don’t want to argue global warming in this thread, please keep that elsewhere.
If we concede it could be a problem and the oceans may slowly rise, then New Orleans could become the test city for how to protect all other coastal cities.
If worse case Global warming is true, NYC, DC, Boston, Baltimore, etc. will all need large projects to protect them.
New Orleans can be a mutual beneficial research project. We as a country would be building a safer city and at the same time learning how to best accomplish long term water rising, city sinking strategies.
I didn’t see the interview, but what you’re getting is only part of the picture. In the context of the actual article, that is the outcome if we continue the way we are. Half of the article, however, discusses the consensus plan, Coast 2050, that was reached in 1998 for saving the city and restoring the delta.
Regardless of whether the current global warming trend is anthropogenic or not, it is becoming increasingly hard for anyone to deny that average temperatures are increasing, and if that trend continues an inevitable side effect of that change is going to be rising sea levels, and potentially more (and more powerful) hurricanes and tropical storms. In agreement with jrfranchi’s point, if we don’t have the technology and willpower to save NOLA, then I certainly wouldn’t want to invest in any Manhattan, LA or Miami properties over the next few decades, as there is a strong likelihood that they will be next.
I just read the SciAm article. Holy Og.
This would make the building up of barrier islands and wetlands the #1 priority.
Levees alone really would be at best a short term solution.
So, fix Levees, start barrier islands and wetlands project. Raise the lowest areas. Keep them as greenways until raised sufficiently high. Consider the entire project to be a giant R&D & public works project.
No, I don’t believe that every coastal area needs to move. I do, however, think that some areas are way more perilous than others. To consider rebuilding a city that is already below sea level and no long-term plan to make it safe is just wrong.
I tend to be more of a hardass about this because of my 25 year career as an insurance adjuster. There’s a fine line between acceptable risk and just plain stupid and I’ve seen plenty of stupid over the years.
As another poster said, the “feds” will be picking up the tab for rebuilding NO. I hate to be the one to mention this but WE are the feds. WE will be paying for decades for the devastation created by this storm through increased taxes or insurance premiums.
I’m all for rebuilding if it can be done so that the inevitable can be avoided. To make these decisions based on emotional reasons rather than a sound financial basis will be a huge mistake.
In between listening to NPR today, I put on IMUS.
He had a politico on who started talking sense.
**We have to not just rebuild the levees but we need to rebuild and repair the wetlands and barrier islands. **
Turns out it was Sen. John McCain.
He specifically mentioned the contracts to rebuild need to go to local construction companies and not Haliburton.
He also slammed FEMA.
As I understood it, rebuilding the wetlands and barrier islands was a project in place in 2001 when Bush halved funding for it (when they should probably have been expanded, rather) and thus effectively crippled it.
Ignore my Bush comment for a moment, I just wanted to stress that this was already the accepted option and in progress, so it must have been considered a viable and essential option. I remember this very clearly because we had two individual Dutch engineers on the news who had consulted on the project.