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New York Underground

nationalgeographic.com

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Re: New York Underground

#81

Post by angersock »

rwhitman wrote: post #78
hkmurakami wrote: post #37

Earlier quoted context omitted.

To me, $6 billion seems really cheap for a project that seems pretty vital to the city's long term health, safety and security. Compare this to the ~$10 billion for the California High Speed Rail project, which doesn't seem nearly as important as this NYC project.

Having lived the last 2 years in NYC and the previous 7 in CA I can say that high speed rail is the more valuable project. The water here is fine, and no one is suffering because there isn't a 3rd tunnel. But the transportation situation in California is archaic and frustrating. Have you ever been trapped in traffic on the grapevine for 4 hours trying to get to/from LA? Or shelled out $300 for an hour flight to SFO?…

Perhaps, but consider what happens if something does go wrong with the water supply--this is not something that can be patched overnight.

A rail system is well and good, but you can at least take a car or bus if you need to. If your water infrastructure stops working, there aren't many other games in town.

Re: New York Underground

#82

Post by tallanvor »

yskchu wrote: post #13

The most interesting I found was the steam pipes.

Steam pipes are pretty common and can be quite economical. Besides New York, you'll find them in Seattle, San Francisco, and a number of other large cities in the US, as well as all over Europe. On a small scale, a number of institutions run them as well - IIT in Chicago, for example, has a central steam plant.

Re: New York Underground

#83

Post by nikcub »

msutherl wrote: post #31

So, there are two of those deep underground water tunnels, one which runs down from the Bronx through Manhattan and another that runs from the Bronx through Queens and Brooklyn. These tunnels were completed in 1917 and 1935 respectively. How they managed to do this then is beyond me. Currently a third tunnel is being built and apparently it's "the largest construction project in New York history". The project was beg…

A must-read on the water tunnel project underneath NY is David Grann's article for the New Yorker 'City of Water'[1]. Mind-blowing engineering project, especially the two old tunnels and their inability to repair them. It is one of the most read and most requested stories in the recent history of the New Yorker.

The article was syndicated in his book, The Devil and Sherlock Holmes, which is worth a read[2].

[1] http://www.newyorker.com/archive/2003/09/01/030901fa_fact_gr...

[2] http://www.amazon.com/The-Devil-Sherlock-Holmes-Obsession/dp...

Re: New York Underground

#84

Post by ry0ohki »

rwhitman wrote: post #78
hkmurakami wrote: post #37

Earlier quoted context omitted.

To me, $6 billion seems really cheap for a project that seems pretty vital to the city's long term health, safety and security. Compare this to the ~$10 billion for the California High Speed Rail project, which doesn't seem nearly as important as this NYC project.

Having lived the last 2 years in NYC and the previous 7 in CA I can say that high speed rail is the more valuable project. The water here is fine, and no one is suffering because there isn't a 3rd tunnel. But the transportation situation in California is archaic and frustrating. Have you ever been trapped in traffic on the grapevine for 4 hours trying to get to/from LA? Or shelled out $300 for an hour flight to SFO?…

How much will train tickets cost? Taking the high speed rail from DC to NYC costs about the same as flying.

Re: New York Underground

#85

Post by nosse »

wtvanhest wrote: post #67
greyboy wrote: post #65

Earlier quoted context omitted.

Not personal photos, but here are some examples: http://www.cclockwood.com/stockimages/WE-HURRICANE-GUSTAV-46... http://www.doc.state.nc.us/news/scrapbk/David-1.jpg http://www.city-data.com/disaster-photos/photos/220.jpg http://www.cclockwood.com/stockimages/WE-HURRICANE-GUSTAV-46... http://4.bp.blogspot.com/-m6YoyhPEom8/Tlpzy9dkJII/AAAAAAAABY... http://ww2.hdnux.com/photos/05/20/46/1378705/5/628x471.jpg Google somet…

I grew up in south florida and have witnessed a bunch of root walls, but It really depends on the tree. Palm trees for examples have deep root structures and small canopies which is how they survive the strong tropical winds.

Pines too often have a big and strong main root. It's for collecting water from deep layers. It can be all-most as thick as the tree itself.

Re: New York Underground

#86

Post by nosse »

gee_totes wrote: post #16

I'm no civil engineer, but why are the sewage tunnels above the clean water tunnels? If there were a leak, wouldn't the sewage seep into the clean water? Or is the clay thick enough to provide a good barrier?

It doesn't matter much. Clean water tunnels have high pressure and good walls to keep anything out. Just plain soil getting into clean water tunnel can make loads of people really sick. If there is a clean water leak, they know it from pressure drop.

If there would be a leak in sewage, the biggest problem would be ground water getting into the sewage tunnel, and flooding the water treatment plant. There is probably larger pressure in ground water than in the sewage. Ground water pressure drop can also make foundations of buildings to get looser, so they try to monitor leaks to the sewage (little leaking is btw quite common in older ceramic/concrete pipes).

Sewage system works by gravity. That makes it sometimes really difficult for positioning the pipes. They must have either 2 - 7 % slope or they must be vertical. Uphill inside a sewage tube will gather all the shit and get stuck. With more than 7% slope the water runs too fast away from the pipe and leaves the shit behind, so again it will get stuck eventually.

PS. I used to study civil.

Re: New York Underground

#87

Post by nosse »

lobster_johnson wrote: post #69

Naive question, but are things like power, gas, water, TV cables and steam always buried like this (requiring digging to make repairs or modifications), or are there cities/systems where they are laid in human-accessible tunnels? Seems like it would be more practical, albeit more expensive.

In Helsinki they have human accessible tunnels because the whole city is on bedrock and there is not much soil above it. It's just way too hard to make tunnels to rock so small that people can't go there, so they're forced to be more accessible.

Tv, gas and power can be digged relatively shallow and I have not hear of maintenance tunnels for them when there is no solid rock to deal with.

With sewers they usually put vertical wells to it in every corner. That makes the whole system more accessible.

Often they put empty plastic tubes to new buildings just in case. It's not very hard to get something crawling there when new Internet comes to house.

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