Use broken buildings to raise New Orleans above sea level.

[MyUncle]

Just read an article about the monumental task of where to put all of the debris from Katrina - http://www.msnbc.msn.com/id/9375252/

A simple solution? Since the below sea level houses are going to have to be destroyed, why not make those areas of town the recipients of the debris/land fill and raise the level of land there so it is ABOVE sea level.

Then give the houses/businesses back to those who were displaced? 10 feet above sea level means thy won't flood next time.

Is this too easy?

[achtung_circus]

1. Yes, it is too easy.

Frame buildings, those constructed primarily of wood make lousy fill.

Organic matter deteriorates. Good fill needs to be not only inorganics, but the right size inorganic particles.

[madmax]

2. Didn't they use crushed shells to build on

Manhatten? :shrug:

[benburch]

3. Yes.

And that has been a problem ever since.

[SOteric]

7. Whereas Seattle was built right over the top of

the burnt down husk of the old city and even turned into a tourist attraction. They left the old buildings intact and recreated a series of vignettes in the streets and homes.

Of course, as wet as it is hereabouts, it's not below sea level. And while I wouldn't want to be down there in an earthquake, we don't have to work out how to hold backt he mighty Mississippi ever dad gummed day.

[ovidsen]

9. I don't think so.

Manhattan is solid rock covered with a thin layer of soil, and almost all of it is above sea level. There's some landfill (Battery Park City, for example), but if you walk through Central Park or Riverside Park, you'll see a lot of outcroppings (some very large) of a slightly sparkly gray rock known as Manhattan schist. It's one reason why most NYC subway tunnels are "cut and cover" (dig a trench, lay tracks, cover it up and pave it and poof! a subway) rather than deep tunnel. It's fairly easy to deep tunnel through clay (a la London) but tunnelling thru solid rock is a bitch.

Enjoy the view:

http://www.newyorkcitywalk.com/html/images_schist.html

[TallahasseeGrannie]

4. I think it would rot

in the heat and moisture and with all the bugs and just sink lower and lower. Not a lot of cement in the rubble from what I can see. Mostly frame houses.

But stilts might be a good idea! Really high ones.

[lithiumbomb]

5. bad fill

Like someone else said, this will not make stable fill material. Certainly not in an area that I'm sure has a very high water table. It can be used for fill in some cases, probably ok for a parking lot or land without buildings on it (field, park) if compacted properly.

[newyawker99]

14. Hi lithiumbomb!!

Welcome to DU!! :toast:

[shraby]

6. The debris will all be too contaminated

with God only knows what all. That contamination will seep into the ground and cause more problems down the road, not to mention that all the organic material will rot away and the city will once again sink.

[Syncronaut Seven]

8. They built the Seattle waterfront district on sawdust

They still have problems with methane pockets and settling.

However, with the levees to contain and define the shape I would think crushed inorganics would fill the bill quite nicely.

With the toxic stew left behind, it might be cheaper to fill than excavate, but who would decide what shape the new city would take? Crushing the Superdome for fill would be a nice symbolic gesture.

[TahitiNut]

10. It's nonsense.

Most building materials (and debris) decompose over relatively short periods of time (more than months and less than eons). When these materials decompose, the 'ground' upon which foundations are built settles and shifts. That destroys foundations. When foundations are destroyed, the buildings collapse.

When thinking of the above-ground parts of a city, we tend to forget about the more essential parts of the infrastructure below the surface: sewers, water lines, gas lines, etc. Access is essential. A flooded sewer is less than useless.

The biggest mid-term problem in NOLA (and environs) is the toxicity of the land and structures inundated by sewage-laden (and chemical-laden) floodwaters. The clean-up will be staggering. Or it would be if we cared enough about the poor people who'll be relegated to living there.

[MyUncle]

11. Leave the neigborhoods under sea level???

That is not the answer.

I lived in Singapore where, conservatively, they doubled the land mass of their country through land fill.

Yes, the materials might not be "perfect", yes there could be settling, yes it might not be sterile materials we would use to fill, BUT it is a solution.

This solution might in 15 to 20 years need some repair work. But you have to fix the basic problem of flood waters going to low points in the city. If you don't build up, it will flood again.

[pitohui]

12. well not all the neighborhoods hard hit were under sea level

some of this was a freak occurrence

neighborhood of gentilly terrace might never be underwater again for example

a big issue is that MUCH of the flooding occurred outside the flood plain, in zone C which is the designation for a "no flood" area

don't assume only the lowest-lying neighborhoods were flooded, this was not in fact the case

some fine neighborhoods on higher ground such as old metairie were in fact flooded but might not have this prob. agn for decades or centuries

[cally]

13. I think this should be considered

Some of the debris could be used. Certainly, some of the concrete from roads and foundations. The organic matter could be ground and used for parks. The wood from very old homes may not be contaminated like modern products are. We have to find something to do with all this garbage. It's time to get creative IMHO.

Much of the fill in San Fran was from old ships and the fire. It's horrible in earthquakes.