The City That Plans to be Flooded

By: Douglas Hill , 2:22 PM GMT on December 02, 2011

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A guest post by Douglas Hill, a consulting engineer and an adjunct lecturer at the School of Marine and Atmospheric Sciences at Stony Brook University in New York.

Hurricane Irene, remember? Irene, diminished to a mere tropical storm when it struck New York City, came and went, soon disappearing from the news. But think back to August 26 when Irene, a Category 3 hurricane with winds of more than 110 miles per hour, was approaching the North Carolina coast and headed directly for New York City. Mayor Michael R. Bloomberg called a news conference to order 370,000 people to evacuate their homes. Then he stepped aside, and MTA chairman Jay Walder stepped to the microphone and announced that public transportation--buses as well as trains--was being shut down.


Figure 1. GOES-East visible satellite image of Irene taken at 7:45 am EDT on Sunday, August 28, 2011. At the time, Irene was a tropical storm with 65 mph winds, making landfall on Long Island, New York. Image credit: NOAA Environmental Visualization laboratory.

Evacuation without transportation: a novel concept that the mayor described as "preparing for the worst and hoping for the best." Fortunately, hoping for the best worked.

Unfortunately, the City is still hoping for the best, and it is not preparing for the worst. The coastal storm plan of the Office of Emergency Management (OEM) includes strategies for storm tracking, public information, evacuation procedures, people with special needs, recovery, and restoration, but nothing to prevent flooding.

In other words, New York City is planning to be flooded--and according to the National Hurricane Center, it will be. Based on the historical record, hurricanes of Categories 1, 2 and 3 will strike the New York region on an average of every 17, 39 and 68 years, respectively. The City has been overdue for a Category 1 hurricane--Irene should have been no surprise--and we may expect hurricanes of Categories 2 and 3 within the next decade or two. In testimony to a U.S. Senate committee, Max Mayfield, the former director of the National Hurricane Center, said, "It is not a question of if a major hurricane will strike the New York area, but when" (his emphasis.)

The greatest potential for loss of life from a hurricane has historically been from the storm surge. If the eye of a Category 3 hurricane crossed the New Jersey shore, the surge could reach 24 feet--compared with 4.5 feet in Hurricane Irene's--flooding the World Trade Center site and Wall Street, with City Hall resting on a separate island south of the rest of Manhattan. The ripples from a crippled financial district in lower Manhattan would be felt worldwide. In a severe hurricane, the OEM has estimated that up to three million people would have to evacuate, if that can be imagined.



Figure 2. The height above ground that a mid-strength Category 2 hurricane with 100 mph winds would push a storm surge into New York City in a worst-case scenario. The image was generated using the primary computer model used by the National Hurricane Center (NHC) to forecast storm surge--the Sea, Lake, and Overland Surge from Hurricanes (SLOSH) model. The accuracy of the SLOSH model is advertised as plus or minus 20%. This "Maximum Water Depth" image shows the water depth at each grid cell of the SLOSH domain. Thus, if you are inland at an elevation of ten feet above mean sea level, and the combined storm surge and tide (the "storm tide") is fifteen feet at your location, the water depth image will show five feet of inundation. This Maximum of the "Maximum Envelope of Waters" (MOM) image was generated for high tide and is a composite of the maximum storm surge found for dozens of individual runs of different Category 2 storms with different tracks. Thus, no single storm will be able to cause the level of flooding depicted in this SLOSH storm surge image. Consult wunderground's Storm Surge Inundation Maps page for more storm surge images of the U.S. coast.

Other major ports have taken measures to prevent being flooded. After the 1938 hurricane, storm surge barriers were built in New England to protect New Bedford, Providence and Stamford. After a disastrous storm in the North Sea in 1953, the Thames Barrier was built to protect London, and the Delta Plan was started in the Netherlands which includes three such barriers, one protecting Rotterdam, Europe's busiest port. Following Hurricane Katrina, a long-disputed barrier was constructed at the entrance to Lake Pontchartrain along with several others, which are now considered to make New Orleans hurricane-proof to Category 3 storms. Barriers are being completed to protect St. Petersburg, Russia, and Venice, Italy.

The heart of New York City could be protected in the same way. Moveable barriers, closed only when the city is threatened with major coastal flooding, could be placed at the upper end of the East River, across the Narrows and at the mouth of the Arthur Kill. Possibly, the latter two could be replaced with a single, longer barrier extending from Sandy Hook to the Rockaway peninsula. Modeling studies have demonstrated that the barriers would work. Four major engineering firms have presented conceptual designs and cost estimates for barriers at these locations. The estimated costs for these individual barriers range from $1 billion to $4.6 billion, with the total of the two or three needed less than $10 billion, comparable to other major infrastructure projects planned or underway.


Figure 3. Proposed hurricane storm surge barrier for New York City near the Verrazano Narrows Bridge. Image credit: Arcadis, Inc.

But unlike the original, the 2010 revision of plaNYC, the City's principal planning document, makes no reference to storm surge barriers. The City's latest plans are seen in the March 2011 Vision 2020: NYC Comprehensive Waterfront Plan, which calls not for protecting the waterfront, but for climate "resilience," the ability to withstand and recover from the disaster. Unfortunately, this may be the best that can be done for those living in the coastal sections of the boroughs that face the Atlantic Ocean.

So the Great Evacuation of August 2011 is a test. In its postmortem on the storm on September 5, the New York Times concluded that "by almost any measure, the evacuation was a success," but it did not report on the principal measure. How many people were left behind? Unlike New Orleans after Katrina, we won't know by counting the bodies. Not this time, anyway.

Douglas Hill, EngScD, P.E., Stony Brook University

Other posts in this series
Storm surge barriers: the New England Experience
Hurricane Irene: New York City's close call

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I finally figured out how to change my blog profile. Another dumb moment recorded for SPLbeater =P
Member Since: August 4, 2011 Posts: 46 Comments: 4481
That line of T-storms is in the area 99L, 90L were, and it is now playing tricks with my mind xD
Member Since: August 4, 2011 Posts: 46 Comments: 4481
is way too quiet....
Member Since: August 4, 2011 Posts: 46 Comments: 4481
Thank God Texas was not a major target for Allied bombing in WWII.. (what the Hll us he talkin' about???)
Major drought in Berlin causes river level to lower enough for an unexploded 1.8 TON bomb to be exposed.. yikes! article link here
Member Since: September 9, 2010 Posts: 5 Comments: 1034
Quoting SPLbeater:
It is a small, but healthy looking blob on your sat pic.....Floods a comin..
Member Since: September 27, 2007 Posts: 1 Comments: 20505
Member Since: August 4, 2011 Posts: 46 Comments: 4481
98S
Member Since: August 4, 2011 Posts: 46 Comments: 4481
Quoting AussieStorm:
Snow forecast for next 3 days.







Link
Morning Aussie..We are wet. Unfortunately, we will get wetter. Big wad of drenching rain right smack dab where we do not need it..Too bad I couldnt Fed-Ex it to Texas...The ground in that huge state would suck that rain up like a huge thirsty beach towel. Texas will get some tho.
Member Since: September 27, 2007 Posts: 1 Comments: 20505
Descending pass JUST missed the entire circulaton lol...Western 2/3 anyways.
Member Since: August 4, 2011 Posts: 46 Comments: 4481
WTXS21 PGTW 030830
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN 160 NM EITHER SIDE OF LINE FROM 11.7S 69.2E TO 14.4S 67.3E WITHIN THE NEXT 24 HOURS. AVAILABLE DATA DOES NOT JUSTIFY ISSUANCE OF NUMBERED TROPICAL CYCLONE WARNINGS A THIS TIME. WINDS IN THE AREA ARE ESTIMATED TO BE 25 TO 30 KNOTS. METSAT IMAGERY AT 030730 INDICATES A CIRCULATIN CENTER IS LOCATED NEAR 11.9S 68.9E. THE SYSTEM IS MOVING WEST-SOUTHWESTWARD AT 06 KNOTS.
Member Since: August 4, 2011 Posts: 46 Comments: 4481
Snow forecast for next 3 days.







Link
Member Since: Posts: Comments:
Quoting Articuno:

what's that supposed to mean? O_0


It's a perl script for playing tic-tac-toe
Member Since: Posts: Comments:
Quoting CaicosRetiredSailor:
Good "morning" night shift...
from up on a rainy mountain above Kingston Jamaica.
...at a "dream" of a place
certainly as beautiful as any dream I have had:
Rafjam B&B
Good morning CRS..I dont mind saying that I wish I was there..It is very cold on the Cumberland Plateau, Middle Tennessee.
Member Since: September 27, 2007 Posts: 1 Comments: 20505
Quoting HadesGodWyvern:
Madagascar Meteorological Services
12:00 PM UTC analysis of cyclone activity

TROPICAL DISTURBANCE (01-20112012) <-- (number according to their site, unofficial)
Center: 12.6S 69.4E
Pressure: 1000 HPA
10 min winds: 25 KT (45 KM/H)
Gusts: 35 KT (65 KM/H)
Dvorak: CI 2.0
Movement: SSW 04 KT (07 KM/H)
Additional Information: SHEAR PATTERN


Madagascar Meteorological Services surface map


98S


Member Since: Posts: Comments:
149. HadesGodWyvern (Mod)
Madagascar Meteorological Services
12:00 PM UTC analysis of cyclone activity

TROPICAL DISTURBANCE (01-20112012) <-- (number according to their site, unofficial)
Center: 12.6S 69.4E
Pressure: 1000 HPA
10 min winds: 25 KT (45 KM/H)
Gusts: 35 KT (65 KM/H)
Dvorak: CI 2.0
Movement: SSW 04 KT (07 KM/H)
Additional Information: SHEAR PATTERN


Madagascar Meteorological Services surface map
Member Since: May 24, 2006 Posts: 50 Comments: 44738
Tropical Cyclone Three Day Outlook for the Western Region

IDW10800
Australian Government Bureau of Meteorology
Western Australia

Tropical Cyclone three-day outlook for the Western Region
Issued at 2:00pm WST on Saturday the 3rd of December 2011
Valid until midnight WST Tuesday


Existing Cyclones in the Western region:
Nil.

Potential Cyclones:
A weak low has developed near 08S 097E. The low is expected to drift south of
10S into the Western Region during Sunday. It should then move westwards, and is
expected to pass west of 090E during Monday. The low may develop into a cyclone
during Monday or Tuesday, but is likely to remain below cyclone strength until
it moves west of 090E.

Likelihood of this system being a tropical cyclone in the Western Region:
Sunday :Low
Monday :Moderate
Tuesday :Low [out of the area]

There are no other lows expected in the Western Region over the next three days.


NOTES: Development Potential is an estimate of the chance of each system being a
tropical cyclone in the Region for each day.
Very Low: less than 5% Low: 5% - 20%,
Moderate: 20% - 50% High: Over 50%

The Western Region refers to the Indian Ocean between Longitudes 90-125E and
south of 10S.
Member Since: Posts: Comments:
Quoting Cotillion:
Seems to be the time of year for Katla-mongering.

Katla isn't ready to erupt yet from the looks of things (it may have had a minor subglacial eruption earlier this year), though it seems to be making the rounds. I suppose there's not enough doom in the world currently.

Katla tends to go to about a 5 at most (whenever it does erupt, which no-one but Katla herself knows), which would be bigger than the two recent ones (Plinian, so it's dangerous enough if it erupted at such a level), but a global disaster is a bit much. Certainly it's one of the Icelandic volcanoes which is a bit more dangerous and would cause aviation disruption (though the ash and pyroclasts may be of a different consistency to last year's) and certainly problems in Iceland itself.

I am more interested in this statement. A statement on Iceland's Met Office website warned there was no imminent threat but that "given the heightened levels of seismic activity, the situation might change abruptly."

I would say they know more than anyone about Katla. Maybe she might stay at this heightened level for a few days or months and come back to back ground levels, but then again, she might just blow her top. We wont know until either happen.
Member Since: Posts: Comments:
Anyone know if this earthquake is associated with the 5.8 virginia one. It's in sw va and its far away from the main quake..
Member Since: October 22, 2011 Posts: 0 Comments: 2293
Quoting hydrus:
&(&&^&*($@)_ _)()*&(...:)

what's that supposed to mean? O_0
Member Since: October 22, 2011 Posts: 0 Comments: 2293
144. DDR
Hi pottery
i though we would got away,guess i was wrong la nina kicking in again,just 1.5 inches since midnight.
Member Since: April 27, 2007 Posts: 14 Comments: 1686
Quoting CaicosRetiredSailor:
Good "morning" night shift...
from up on a rainy mountain above Kingston Jamaica.
...at a "dream" of a place
certainly as beautiful as any dream I have had:
Rafjam B&B

Looks like a bit of Paradise!
Sorry about the rain...

Here, it has been coming down continuously since about 11:00 pm last night.
A cloud is parked overhead....
Member Since: Posts: Comments:
Seems to be the time of year for Katla-mongering.

Katla isn't ready to erupt yet from the looks of things (it may have had a minor subglacial eruption earlier this year), though it seems to be making the rounds. I suppose there's not enough doom in the world currently.

Katla tends to go to about a 5 at most (whenever it does erupt, which no-one but Katla herself knows), which would be bigger than the two recent ones (Plinian, so it's dangerous enough if it erupted at such a level), but a global disaster is a bit much. Certainly it's one of the Icelandic volcanoes which is a bit more dangerous and would cause aviation disruption (though the ash and pyroclasts may be of a different consistency to last year's) and certainly problems in Iceland itself.
Member Since: August 23, 2008 Posts: 7 Comments: 5300
Iceland volcano Katla sparks global disaster fears.

. More than 500 tremors detected at volcano Katla
. An eruption could cause catastrophic flooding
. Eruption could also disrupt air travel


A HUGE Icelandic volcano long overdue for an eruption is showing signs of activity that could disrupt air traffic, experts reported.

There have been more than 500 tremors at Katla in the south of the country in just the last month.

An increase in activity at the site since July has also been causing concern among volcano experts.

The last major eruption at the volcano was in 1918, and caused such a large glacier meltdown that icebergs were swept into the ocean by resulting floods.

Significant activity at Katla -- which has a huge 6.2 mile (10 km) crater -- usually occurs every 40 to 80 years.It is feared when it does eventually erupt, it could be the most powerful volcano activity the country has seen in almost a century.

Catastrophic flooding could result as the frozen surface of the volcano melts, sending vast amounts of water into the Atlantic Ocean.

Volcano expert Andy Hooper from Delft University said that while there had been increased activity at the site, it was difficult to predict if and when Katla would erupt.

However, he said that the implications for Iceland if an eruption did occur would be "major."

"Because of the glacier on top, massive amounts of ice would melt, washing away the roads.

"There could also be a big ash fallout on people living in the area and that will affect the farms.

"There could be big implications for people there.

"In terms of the rest of the world, it really depends on the weather at the time of the eruption.

If Katla erupts, it will erupt higher (than recent volcanoes) and that means the ash will stay around longer -- that could impact on air traffic."

A statement on Iceland's Met Office website warned there was no imminent threat but that "given the heightened levels of seismic activity, the situation might change abruptly."

In 2010, the eruptions at Iceland's Eyjafjallajökull volcano disrupted air traffic for weeks, affecting hundreds of thousands of travellers.
Member Since: Posts: Comments:
Interesting spin beneath bermuda..light winds though. Would be cool to see some convection burst over it, heh
Member Since: August 4, 2011 Posts: 46 Comments: 4481
Good "morning" night shift...
from up on a rainy mountain above Kingston Jamaica.
...at a "dream" of a place
certainly as beautiful as any dream I have had:
Rafjam B&B
Member Since: Posts: Comments:
Much better in this descending pass:D

I would call the LLCC near 9S, 96E
Member Since: August 4, 2011 Posts: 46 Comments: 4481
Quoting sunlinepr:
Big Cane Central ATL?







cmc, very very unlikely
Member Since: August 4, 2011 Posts: 46 Comments: 4481
Big Cane Central ATL?





Member Since: Posts: Comments:
man wake up blog, lol
Member Since: August 4, 2011 Posts: 46 Comments: 4481
Quoting WeatherNerdPR:

It's structure's a bit linear though, what a pity, would've been cool to have Tammy in December.


yep. sad
Member Since: August 4, 2011 Posts: 46 Comments: 4481
Quoting SPLbeater:


i been watchin that all day, nice little spin there

It's structure's a bit linear though, what a pity, would've been cool to have Tammy in December.
Member Since: Posts: Comments:
Quoting WeatherNerdPR:


i been watchin that all day, nice little spin there
Member Since: August 4, 2011 Posts: 46 Comments: 4481
Member Since: Posts: Comments:
130. HadesGodWyvern (Mod)
Jakarta Tropical Cyclone Warning Center
Tropical Cyclone Outlook
9:06 AM WIT December 3 2011
====================================

Suspect area with minimum pressure (1006 mb) is observed in Indian Ocean near 8.3S 96.0E, or about 1213 km west-southwest of Jakarta, Indonesia. The system is reported as moving southward slowly.

Tropical Cyclone Formation Potential
======================================

Sunday: Moderate
Monday: Moderate
Tuesday: Moderate
Member Since: May 24, 2006 Posts: 50 Comments: 44738
2011 vs 2005

Unnamed October subtropical storm of 2005
October 4-5 50mph 997mb


and unnamed tropical storm of 2011
Sept 1-2 45 mph 1002 mb




In both years (the same set of names used) there was a unnamed storm...
Both storms lasted about 1 day and were added in the post storm analysis
how coincidental!
Member Since: Posts: Comments:
anybody think i should issue my own TWO? that is an aggressive idea, knowing my attitude lol....anyone?
Member Since: August 4, 2011 Posts: 46 Comments: 4481
Member Since: Posts: Comments:
Quoting Articuno:

...lol
&(&&^&*($@)_+_)()*&(...:)
Member Since: September 27, 2007 Posts: 1 Comments: 20505
Quoting washingtonian115:
I hope we're talking about the same period like in the end of a sentence.ROFLMfAO.

...lol
Member Since: October 22, 2011 Posts: 0 Comments: 2293
Quoting yqt1001:
I was actually going to make my own website for it, but I wouldn't mind having someone that would be able to work opposite "shifts" as me (so instead of 12 hourly updates, there would be 2 forecasters making 6 hourly updates). It's still an idea and likely will remain that for a few more months anyways. :P

I'm always available :P
Member Since: July 6, 2010 Posts: 113 Comments: 31456
why my comment number 781 did not show up i have no clue.
Member Since: August 4, 2011 Posts: 46 Comments: 4481
Tropical Storm UNNAMED's track:
Member Since: Posts: Comments:
I was actually going to make my own website for it, but I wouldn't mind having someone that would be able to work opposite "shifts" as me (so instead of 12 hourly updates, there would be 2 forecasters making 6 hourly updates). It's still an idea and likely will remain that for a few more months anyways. :P
Member Since: November 19, 2010 Posts: 1 Comments: 1285
Off Topic, but the probe that could have given us valuable information about Mars' moons is dead.
Is Phobos Grunt Dead?
Europeans end rescue effort
Member Since: Posts: Comments:
Quoting Skyepony:


LOL~ well I started off watching the recent wind storm. You know how youtube goes for me..my weather perusing there tonight ended with this serious warning for tornado chasers.
Excellent video Skye ;0..Thanks for sharing..We are going to get whacked with heavy rain again in Tennessee.
Member Since: September 27, 2007 Posts: 1 Comments: 20505
JTWC 1:30UTC seems positive for development.

2. SOUTH INDIAN OCEAN AREA (135E WEST TO COAST OF AFRICA):
A. TROPICAL CYCLONE SUMMARY: NONE.
B. TROPICAL DISTURBANCE SUMMARY:
(1) THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 6.7s 96.0E, IS NOW LOCATED NEAR 8.3S 96.0E APPROXIMATELY 655 NM WEST-SOUTHWET OF JAKARTA, INDONESIA. ANIMATED INFRARED SATELLITE IMAGERY AND A 022016Z AMSU MICROWAVE IMAGE IMDICATE PERSISTENT CONVECTION AND IMPROVED LOW LEVEL BANDING WRAPPING INTO A WEAK LOW LEVEL CIRCULATION CENTER OFF THE COAST OF SUMATRA. A 021642Z SCATTEROMETRY PASS SHOWS 20 TO 25 KNOT WINDS AT THE CENTER. UPPER LEVEL ANALYSIS REVEALS THAT THE DISURBANCE IS LOCATED WITHIN A REGION OF MODERATE VERTICAL WIND SHEAR. HOWEVER, AS THE SYSTEM TRACKS SOUTHWARD TOWARD THE RIDGE AXIS, VWS SHOULD SUBSIDE AND MAY ALLOW A WINDOW FOR FURTHER DEVELOPMENT. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 20 TO 25 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1006 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS REMAINS MEDIUM.
Member Since: August 4, 2011 Posts: 46 Comments: 4481
the wxgeekva unofficial tropical weather center outlook for 8pm est:

an area of low pressure formerly tagged 90l near 35n 55wby the national hurricane center is located in the central atlantic several hundred miles to the northeast of bermuda. the low is producing disorganized showers and storms, but due to the water temperatures under 23 degrees celsius and high southwesterly shear is not expected to develop. the wxgeekva forecast center is giving this system a 10% chance of subtropical development before it is absorbed into a frontal system.

a low pressure area located near 30n 35w is attempting to develop a surface low. the upper level conditions are not favorable for development into a subtropical storm at this time, and we are giving it a near 0% chance of development.

wxgeekva
Member Since: Posts: Comments:
You know i was just looking at the ASCAT pass from earlier today...and it appears each blob has its own LLCC, look:

There is a CC near 96.5E 8.5S, and apparently one near 98E 7.5S. i think the one to the SW will take over though


Member Since: August 4, 2011 Posts: 46 Comments: 4481
Quoting TropicalAnalystwx13:

You can do your own Tropical Weather Outlooks, but you cannot have it formatted the same or have it looking the same.


Ok. I will use a different font and in all lower case letters than the real TWO.
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Quoting TropicalAnalystwx13:

You can do your own Tropical Weather Outlooks, but you cannot have it formatted the same or have it looking the same.


i would try that but i have no idea how to create something like a TWO lol
Member Since: August 4, 2011 Posts: 46 Comments: 4481
Quoting Hurricanes101:


Didnt they say they would also name the system that came across Florida this year?

They even acknowledged it would be classified in post-season but they did not name it at the time due to continuity since the East Coast of Florida already had high wind warnings and such.





they where but not any more
Member Since: May 21, 2006 Posts: 5091 Comments: 114720

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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.