Rebuilding New Orleans

That's the problem with you OldRegular, you lack perspective.
Building cities below sealevel is fine it simply means proper precautions need to be taken.

Like many men you think size is everything...
A dike's success is based on it's strength and not on how thick it is. </font>[/QUOTE]It is really quite simple. If the storm surge is big enough even a wide rim will not prevent the bowl from being filled.

 

This is not necessarily true. If the levee's are built to withstand a category 5 storm, why wouldn't it prevent the "bowl from being filled" as you put it?

 

This is not necessarily true. If the levee's are built to withstand a category 5 storm, why wouldn't it prevent the "bowl from being filled" as you put it? </font>[/QUOTE]A Cat. 5 or greater hurricane can have a storm surge of 30-40 feet. Do you want the levees to be that high?

 

OldRegular
The Deltawerken in the Netherlands can handle storm surges of that size.

 

Mioque

A quick check of the Atlantic cat 5's would indicate that cat 3's seem to be the only storms that regularly hit the low lands. I doubt that your dikes would do well against a real cat 5 ... The northern atlantic slows down hurricanes ...

 

OK - a hurricane (even a small one) is like carpet bombing an area using NUCLEAR warheads.

Storm surge is the most feared ... but not for what we have seen in New Orleans. This was a failure of the levee walls.

Normally storm surge damage accompanies the storm - hint: try escaping the water with 130+ mile an hour winds ...

Wind damage: it is BAD.

Tornados .... Need we explain those? What about water spouts? Got those too.

RAIN ... RAIN ... RAIN ... It is COMMON TO HAVE 2 inches per hour and it is for long periods of time.
For a hurricane: 1.5 to 2+ feet of rain is a normal amount of rain over an area 1/20th the size of the netherlands. (3,000 square miles for main area ... Nashville got 2 inches from Katrina)

Katrina was very mild for rain ... 1/4th that of Allison (a much weaker storm). During Allison parts of Houston (above sea level) were 20 plus feet under water.

The normal flood fear is FROM RAIN - NOT STORM SURGE ...

 

Would they have to be "that high" if there were 2 or 3 rings of dikes?

 

El_Guero
The Deltawerken are severely overengineered.
The system of dams, dikes and levees would be fine.
It's the cities behind them and the large row of dunes that functions as a natural barrier vs. the sea that would be severely damaged by such a hurricane. And that would mostly be wind damage instead of waterdamage.

 

In Washington D.C.?

 

Mioque

Category 5 - evacuate.

Category 4 - I would evacuate.

Category 3 - The Deltawerken should hold. But, I would still want to evacuate.

 

OldRegular

Mioque's perspective is from living on sheltered water.

She is right, on sheltered water - a category five cannot get to her dikes. Much less drive the storm surge across those dikes.

 

The Dutch government would make you evacuate at level 3 simply because most buildings in the Netherlands are not build to resist hours of hurricane level wind.
Mass evacuation wouldn't be difficult overhere because of the large and reasonably efficient public transport system.
Rebuilding would be relatively easy because the sort of flooding that brought down New Orleans wouldn't be an issue.

 

Mioque

Your perspective is from living on sheltered COLD water. If you ever visit the southern US (especially the Gulf) and a hurricane approaches, forget everything you thought you knew.

Look at the people in New Orleans still going crazy. (Animals go crazy also.) Look at the failue of things, even AFTER you think it is safe (many people get killed because they think it is safe to go out).

 

I'm sure New Orleans will be rebuilt. The city is too important to Louisiana to become a ghost town. And, although this sounds cruel, the people of Baton Rouge simply don't want the thousands of evacuees to settle there permanently. B.R. is basically an oversized small town; no one there wants it to permanently become the state's largest city (along with the inevitable rise in crime, traffic congestion, etc.). It's best for everyone if N.O. is rebuilt, even though this will take a long time and lots of money.

 

rsr

a student of history ... ?

 

The fact that 1 in 5 Galvestonians died in the Great Storm did not help matters.

Galveston and Houston had been in competition for many years prior to the storm to be the major port city of Texas.

Had the Storm not hit, I would predict that Galveston would have become the major port and the Ship Channel would never have been built (at least in it's current size and length).

Houston/Galveston would probably be like the metroplex (Dallas/Ft. Worth), with Galveston as the large city and Houston as the close little brother, though neither would be near the size that Houston is now.

Just two cents from someone with a nickels worth of ideas.

James

 

Would they have to be "that high" if there were 2 or 3 rings of dikes? </font>[/QUOTE]Depends on how big the hurricane is [diameter] and how fast it moves through!