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philipov

Again?! Didn't this same thing happen last year or maybe the one before?

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"Didn't we have record floods last year too?"

"Didn't we have record highs last year too?"

"Didn't we have record tornadoes last year too?"

"Didn't we have record fires last year too?"

Welcome to the age of climate instability.

*Welcome to the age of constant 24/7 sensationalized news cycles. Gotta get those clicks! One doom-n-gloom done, onto the next!

These are the actual results of climate change though. What's being sensationalized here?

How do you come to this definite conclusion? Would this have been something like a two to three sigma event given no climate change? I highly doubt it

Sandy the subway stations were filled with water. There were emergency flood gates built into the tunnels in some places but they weren’t maintained.

It'll probably happen next year and the year after that too.

Every year until the underwriters refuse to underwrite - as is already happening on the gulf coast.

Not with a bang, but with a whimper.

At least in New York the geology permits a seawall, if they get their shit together and build it.

Does a sea wall help with too much rain at once?

No, but better drainage would.

In my sister's ex-subdivision in Houston, the streets were designed to flood, channeling any water away from property and into bayous, rivers, and ultimately the Gulf of Mexico. It worked as designed over several tropical storms. The streets were a mess but everybody's home, driveway, and property stayed dry.

NYC needs a similar effort - change the streets and subways to channel water away from property and into the harbor, while providing means to harden the underground parts that can't get wet. It will be crazy expensive, but it's an engineering & construction problem, not a geographic or climate one.

Dumping water into the harbor only really works if it won't just come right back out onto the land. Most of the flooded areas are at sea level.

Hence the seawall idea.

Though as you may be aware, the 3rd and 5th wards are not so well protected. Low-lying parts of highways are often flooded out, especially during hurricanes.

I don't know about NYC but in general a sea wall could hold back a high tide. A lot of coastal cities flood when there is high rainfall coinciding with a high tide. When the tide is low the rain just drains into the river and out to sea.

In this case though, as far as I can tell it really was mostly a lot of rain at once, i.e. too much for sewers to drain to the sea to prevent flooding. I don't think a sea wall could improve this; only better storm drains could.

I think this was different for Hurricane Sandy, where a storm tide was actually pushing in water from the sea/rivers, which is the scenario where a sea wall would help.

And I suppose often it's a bit of both – storm drains stop working once the sea level is too high.

It does if you can drain into the body of water you are blocking with the seawall.

I'm pretty confident it will happen, there's too much real-estate money to not do it.

The current project has been beset by problems with this as well.

Anywhere with a seawall will have lower flooding inside but more flooding outside. When it was originally proposed at the Narrows, Staten Island, Brooklyn and Queens were not pleased.

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