Nola is built on silt. Due to waterway controls etc., the delta isn’t getting the silt it historically received to keep erosion/subsidence at bay. Cost benefit would say keep the farming/irrigation, diversion due to economics and sacrifice a sinking delta. Not much different from Alexandria+Nile.

Nola should have taken the opportunity to move and rebuild on higher ground.

And where would that be? Hammond? Baton Rouge? Morgan City? Watford Gap service station?

That’s something for geologists to answer. All I can say is the place we know has historically sunk and we know is sinking and will continue sinking in the future due to soil, hydrology, etc., is not the place to rebuild.

Alternatively, it is excellent practice that we all are really going to need. Also, again, go explain that point of view to the Dutch - https://en.wikipedia.org/wiki/Flood_control_in_the_Netherlan...

The Dutch have a lot less land to retreat to than those of us in the states.

Retreat is still very expensive though. Why retreat when you can control the landscape and make it your own?

Maintaining a constant war on water is still a lot cheaper than colonizing the moon or mars; and the ROI is pretty decent.

Oh clearly none of you downvoters watch Yes, Prime Minister

Is the Netherlands sinking though?

Most of the Netherlands only exists due to sheer bloodymindedness. Nearly 20% of it is actually below sea level.

I understand that. But New Orleans is subsiding. It's sinking every year. It's easier to maintain levees if the land beneath them isn't sinking. I don't know why my comment is getting downvoted.

The Netherlands has always been sinking. They just don't seem to care and just keep making more of it. Here's their latest plans - https://www.thestructuralengineer.info/news-center/news/item...

Wouldn't that be nice. Sadly, levees actually contribute to the problem due to several factors (IIRC 2 factors were the blocking of silt deposition and the lowering of ground water levels). The ground water levels are something that can be managed, the silt deposition is something you need to learn to live without.

Thing is, if the land wasn't sinking to begin with, exactly why were you considering levees in the first place? ;-)

Whatever the case may be, if you're building levees, you need to factor in the sink rate of the land around you, among the many factors. And you need to factor in the cost to maintain them indefinitely.

It's an expensive proposition; but by the simple fact that you're alive, standing there, and considering it already, chances are the ROI is worth it.

Yes the Netherlands is sinking. Hilariously enough its because of draught. The entire country is basically man made and a natural disaster. Luckily there is virtually unlimited budget and good engineering to keep things going.