Are New York and other cities vulnerable to NO-type of flooding?

[Armstead]

There's a lot of legitimate 20/20 hindsight about why New Orleans was not better prepared, and why preventative actions like reinforcing the levee system were not done before it was too late.

But all the talk of predictions about New Orleans and knowing this was inevitable because of its geography raises bigger question.

What other cities have similar natural vulnerabilities? And -- more important -- are there steps that are also being ignored to mitigate those problems, or deal with the worst if it happens?

Manhatten Island is surrounded by water, and it's not exactly hilly. And what about the toxic meadows of New Jersey across the river? Could the metropolitan area become similarly flooded if the Hudson River were to swell in a dramatic way?

Just wondering how many other potential New Orleans are being overlooked?

[Tace]

1. All Coastal Cities Are Vulerable To Flooding During Big Storms

But most of them will drain naturally after the storm passes.

[XNASA]

2. Chicago has a truly amazing flood control system.

http://www.chipublib.org/digital/sewers/history5.html

TARP or "Deep Tunnel" consists of a series of tunnels and reserviors, some dug as deep as 360 feet, constructed parallel to Chicago's river systems. The system, nearly complete, will extend more than 130 miles.

TARP is constructed utilizing a tunnel boring machine (TBM) called "the Mole" which cuts a hole 33.5 feet in diameter through bedrock deep beneath Chicago's surface. The same equipment was used to construct the "Chunnel" beneath the English Channel between England and France.

During storms the "Deep Tunnel" system conveys overflow storm water and sewage to storage reservoirs where it is held until the regional Water Reclamation Treatment plants are able to process it. The system works to keep overflow sewage out of the areas waterways.

Another innovation of the system has been the construction of off-stream waterfalls throughout the Chicago area. These artificial waterfalls work like natural ones to oxygenate wastewater before returning it to the river system.

[KharmaTrain]

4. Chicago Is A Sanitation System

Problem was as the city grew it dumped all its sewage into the Chicago River and into the lake that then got into the water supply and led to cholora epedemics.

First, they tried to dig bigger intake tunnels further into Lake Michigan but the city continued to grow and even at 2 miles out sewage was getting in the drinking water. The answer was instead of sending the sewage out into the lake, we'll send it down the Illinois River to Peoria and St. Louis...which is what was done.

Deep Tunnel is still a work in progress, and I can attest it still can't handle a large amount of rain. Several years ago, my parents home, which would flood due to the high water tables and pourous limestone in the area, still would flood during heavy rains, Deep Tunnel or not.

To allieviate the flooding in Chicago, the city had another solution. They just raised the city (then mostly the downtown) by 10 feet...so that buildings had to either elevate themselves and build higher foundations or would build a new entrance on the second floor and the first floor became a basement.

BTW...Chicago did have a major flood in '91...when the river breached into an underground tunnel system and flooded the downtown area. That took nearly a year to clean up and was nowhere near as widespread as this one.

[XNASA]

8. Deep Tunnel is very nearly complete.

It took almost 30 years, but all three reservoirs are online and the river is much cleaner than it has been in 100 years.

Certainly, some places will still flood, but most of Chicagoland has benefited from Deep Tunnel.

Regarding the '91 flood....that had nothing to do with the weather, or with Deep Tunnel.

[KharmaTrain]

11. I Remember The First Blasts

I lived near Howard & McCormick when they started the first tunnel in the late 70's. I can remember those two a day "booms" that rattled windows and nerves for months. At least it helped me get up. LOL.

Yep, the '91 flood was a barge hitting a piling that drove through a tunnel shaft...a totally un-necessary accident, and again, nothing like what we're seeing in NOLA. I drove downtown during the thing and the streets were dry, almost all the flooding was in basements.

I'm not pooh-poohing Deep Tunnel and I know for people around the Chicago and Des Plaines Rivers it's making or going to make a big difference.

The OP asked if a disaster like this could happen in Chicago, and I don't think it could...short of a Tsunami off Lake Michigan...and I'm 40 miles inland and on high ground. All we bitch about here is the cold and the snow.

Cheers.....

[XNASA]

13. I live near Thornton Quarry.

We hear blasting all the time. So I guess we're used to it. Since the blasting only occurs during work hours, and I work downtown, I really don't experience them much.

It was a clever trick to change the direction of the river. I'm sure that people in Peoria weren't very thankful since they got Chicago's untreated sewage for years. Same goes for the folks in St. Louis too.

BTW, you'll never hear me complain about the cold. I rather like it.

[KharmaTrain]

15. Engineering Is Great When It's Maintained

This is upgrading and maintaining the system...to ensure there would be adequate drainage in an area that went from prarie to concrete and asphalt...the water's gotta go somewhere.

If you get a chance, the politics about building that system was intense. What's real amazing is how they build all those tunnels and canals with nothing but pick-axe and a little bit of dynamite.

The NOLA system was/is an engineering marvel, too. And it wasn't the pumping system that failed...or that we know of...it was the aging canal system that gave way. Unfortunately these are two different disasters wrapped in one.

Cheers from the high and dry NW burbs...LOL.

[LSK]

3. not the same

Most cities are somewhat above sea level. A storm surge would temporarily flood for a day, but it would all drain naturally. The problem with NO is that it is below sea level and the water filled it like filling up a bowl of soup.

Also note that Biloxi and Gulfport are no longer flooded.

NO was in a unique situation geographically speaking.

[Armstead]

7. Is Manhatten above sea level?

I'm wondering what would happen if flood levels of Hudson River were high enough and stubborn enough that Manhatten and surrounding areas stayed underwater for a longer duration.

Maybe it has been planned for. Just wondering if similar situations as NO could arise.

[ovidsen]

14. All of Manhattan is above sea level

... except for parts of the subway and the river tunnels.

The highest point in Manhattan is in Fort Tryon Park, near the Cloisters in upper Manhattan. It's about 260 feet above sea level. Upper Manhattan can be quite hilly. At 125th Street and Broadway in Harlem, the #1 IRT subway is on overhead elevated tracks as it crosses a valley.

But parts of lower Manhattan are barely above sea level.

[JHB]

5. The flood danger to NYC isn't so much flooding from the Hudson...

...as it is from a hurricane storm surge: if one comes in from the right direction, the right angle formed by the New Jersey and Long Island coasts would work to amplify the surge (lots of water, forced into a smaller area, has nowhere to go but up). Severe enough flooding would also put NYC's subways, tunnels, and other underground infrastructure under water, also causing lots of problems. However, unlike NO, after the brunt of the storm, the water would start draining off and subsiding. No nightmare surprises from broken levees.

[LeftHander]

6. As the polar ice caps melt....

Due to global warming it is estimated that the sea level rise will shift the coastline miles west of NYC....

All coastal cites will be subject to flooding.

Oh wait I forgot....global warming doesn't exist.

[GreenPartyVoter]

12. This will happen all over the world :^(

[TWiley]

9. Chicago had a major flood once.

Not even close to what happened in N.O. but part of their underground system filled up with water.

[ovidsen]

10. A big hurricane would hammer NYC

New York Times
August 31, 2005
New York City Looks South for Lessons a Storm Can Teach
By SEWELL CHAN

Two decades have passed since the last significant hurricane hit New York - Gloria, in September 1985 - but local officials have been preparing for another one for years.

A Category 3 hurricane could bring a 25-foot storm surge crashing over the financial district, Kennedy International Airport, southern Brooklyn and eastern Staten Island; inundate dozens of other low-lying areas; and force the evacuation of 400,000 to 2.4 million residents.

http://www.nytimes.com/2005/08/31/nyregion/31evac.html?pagewanted=print

Scary stuff.

[MadisonRush]

16. I would just like to interject...

That they are comparing this to the 1906 earthquake in San Francisco. What is happeing in NOLA right now is exactly what is going to happen in the Los Angeles/San Diego area when the earthquake finally hits there. I lived in LA during the riots and the last two big earthquakes. The freeways all fell down and the people started rioting and starting the buildings on fire. That's why I had to get out of there...I moved to Minnesota to get away from that kind of thing...and now I see it all over again...sigh. Oh, and before my brain explodes....WHY ISN'T THE FEDERAL GOVERNMENT DOING ANYTHING TO HELP THOSE PEOPLE!!!!