Friday, December 7, 2012

When the bladder bursts

From the NY Times:

On the last Sunday in October, with the storm on its way, railroad workers in yellow slickers unrolled a 90-foot-long rubber bladder at the gaping mouth of a tunnel on the West Side of Manhattan. They began filling it with water, 32,000 gallons. Once engorged, the bladder stood five feet high. It was a formidable plug intended to defend Pennsylvania Station against Hudson River waters surging from the west into the train yards, and from there into the station.

The bladder stood five feet high once it was filled with 32,000 gallons of water.
The plan, as a news release from the Long Island Rail Road said, was “to fight water with water.”

It looked like a good, prudent idea. Then the storm came.

The force of the rushing water simply shoved aside the bladder — approximate weight, 133 tons — and the flood moved toward Penn Station. Only the pitch of the tunnel diverted it away from the station and into another tunnel. The bladder was left in shreds.

As one railroad worker said, “There was so much water in the yards, you could have gone surfing.”

That episode came to mind on Tuesday morning at the groundbreaking for a 26-acre real estate project at, and above, those same train yards — what Mayor Michael R. Bloomberg said was “one of the largest private developments ever undertaken in the country.” It is called Hudson Yards.

A hefty portion of the project’s 26 acres is within the 100-year-flood plain, just as the World Trade Center development is, farther south. At least for now, Hurricane Sandy does not seem to have slowed the momentum of history, more than two centuries of building right up to the margins of the three islands and mainland that make up New York City. Whatever shorefront once existed at the Hudson Yards site was long ago consumed, along with 300,000 other acres of tidal wetlands, as the city was hardened at its edges. The marshy land may have disappeared, but the tides have not gone anywhere.


Anonymous said...

Idiot engineers!

Didn't they take into account that bigger volumes of moving, oncoming water pressure is usually stronger than smaller volumes of resisting water pressure at rest?

I learned all about that law of inertia in general science class.

Then there's all of that friction and those rough surfaces that could tear at and rupture the balloon!

Anonymous said...

The article states that 300,000 acres of tidal wetlands have disappeared from NYC. Thats 468 square miles.

Could the author of the article have been wrong? The whole of NYC only contains 468 sqauare miles. Hmmmm...a coincidental numerical mistake or just sloppy journalism?

Montgomery Scott said...

I can't change the law of inertial physics!

Anonymous said...

Good point > they are proceeding regardless!

Anonymous said...

I guess the big question is why New Yorkers are not doing something about the Sorcerers Apprentice who is still mindlessly building in area this will be flooded and putting future people in harms way.

The only people with the sense - and backbone - to do something about this do not seem to care.

Is the reason for this that they stand to profit from real estate or they do not really live in NYC and like the mayor, its only their second home?

Anonymous said...

I say, let the hipsters who spent BIG BUCKS for waterfront condos in flood zones, get washed away.

I hear that Noah is building another ark in anticipation of oceans rising due to global warming.

I've already booked passage.

Anonymous said...

Sloppy journalism.

The current rail yard is in Flood Zone A. The platform that they're building over the yard will have an elevation 20' above the yard. They need to wall off the rail yard from the Hudson River to protect against future flooding in the Amtrak North River Tubes, but the platform will be Flood Zone C, if at all.

Queens Crapper said...

Not sloppy journalism at all, had you clicked the link and read the entire article.

Anonymous said...

It is at least a typo, or an omission of key details. I did click through, read it, did some research, and sent an email to NY Times pointing out the error.

There might had been 300,000 sq miles of wetland in the Tri-State Area during the times of Christopher Columbus, but not in NYC.