This article is from the source 'guardian' and was first published or seen on . It last changed over 40 days ago and won't be checked again for changes.

You can find the current article at its original source at http://www.guardian.co.uk/world/2012/nov/02/new-york-subways-hurricane-sandy

The article has changed 9 times. There is an RSS feed of changes available.

Version 6 Version 7
New York City subway repairs: what's going on under ground? An explainer New York City subway repairs: what's going on under ground? An explainer
(4 months later)
We've heard it many times: the damage to New York City's subway system won't be fixed overnight. And although some trains were up and running on Thursday, there are still huge queues for shuttle buses on Friday and bumper-to-bumper gridlock traffic in parts of Manhattan.We've heard it many times: the damage to New York City's subway system won't be fixed overnight. And although some trains were up and running on Thursday, there are still huge queues for shuttle buses on Friday and bumper-to-bumper gridlock traffic in parts of Manhattan.
With millions dependent on New York City's subways and tunnels, repair to the transit system is being watched very closely.With millions dependent on New York City's subways and tunnels, repair to the transit system is being watched very closely.
Here's a round-up of what we know about what's going on underground, with information from the Guardian and elsewhere.Here's a round-up of what we know about what's going on underground, with information from the Guardian and elsewhere.
Is there something we're missing? Have another question? Tell us in the comments. We'll update the explainer over the next week.Is there something we're missing? Have another question? Tell us in the comments. We'll update the explainer over the next week.
Q: Who is working on cleaning up the subways?Q: Who is working on cleaning up the subways?
They are a familiar sight now to residents of Manhattan: MTA employees "unwatering" the subway tunnels. Another group in evidence is the US army corps of engineers (USACE). They've been brought in to assist in emptying out the vehicular tunnels (the Brooklyn-Battery tunnel, Holland tunnel, Queens midtown tunnel) and the New Jersey Path train tunnels. Chris Gardner of the USACE told us that they expect to remove approximately 400m gallons of water from those tunnels alone. The army corps engineers are serious – they're part of a planning and response team based in Illinois and are regularly deployed around the country to help with events like this. Many of them assisted in New Orleans after Hurricane Katrina hit.They are a familiar sight now to residents of Manhattan: MTA employees "unwatering" the subway tunnels. Another group in evidence is the US army corps of engineers (USACE). They've been brought in to assist in emptying out the vehicular tunnels (the Brooklyn-Battery tunnel, Holland tunnel, Queens midtown tunnel) and the New Jersey Path train tunnels. Chris Gardner of the USACE told us that they expect to remove approximately 400m gallons of water from those tunnels alone. The army corps engineers are serious – they're part of a planning and response team based in Illinois and are regularly deployed around the country to help with events like this. Many of them assisted in New Orleans after Hurricane Katrina hit.
Q: How are they going to get the water out? And where will it go?Q: How are they going to get the water out? And where will it go?
In a word: pumps. But the process is more complicated than switching "ON" and watching the water disappear. As New Scientist explained:In a word: pumps. But the process is more complicated than switching "ON" and watching the water disappear. As New Scientist explained:
The flooding itself is unlikely to cause structural problems, says Nick Buenfeld, a civil engineer at Imperial College London, as tunnels are designed to withstand the weight of the ground above. "If you fill the tunnel with water you are pressing back against the external pressure," he says. "You could argue structurally it is in a better state when it is full of water than when it is empty."The flooding itself is unlikely to cause structural problems, says Nick Buenfeld, a civil engineer at Imperial College London, as tunnels are designed to withstand the weight of the ground above. "If you fill the tunnel with water you are pressing back against the external pressure," he says. "You could argue structurally it is in a better state when it is full of water than when it is empty."
Q: Tell me more about these pumpsQ: Tell me more about these pumps
Spencer Akerman at Wired's Danger Room got all the goods on the pumps. He wrote that the Corps is looking at bringing in two types of pumps: a "high-head submersible" and a centrifugal one. The MTA's pump plans, however, aren't as clear. One thing we do know is that the MTA's existing subway pumps (that handle regular rainfall) are bound to be in bad shape.Spencer Akerman at Wired's Danger Room got all the goods on the pumps. He wrote that the Corps is looking at bringing in two types of pumps: a "high-head submersible" and a centrifugal one. The MTA's pump plans, however, aren't as clear. One thing we do know is that the MTA's existing subway pumps (that handle regular rainfall) are bound to be in bad shape.
As Dick Knadle, an engineering consultant explained to New Scientist: "The salt water damages pumping equipment. The damage will be compounded by the fact that there is no power to operate the pumping equipment right now."As Dick Knadle, an engineering consultant explained to New Scientist: "The salt water damages pumping equipment. The damage will be compounded by the fact that there is no power to operate the pumping equipment right now."
Q: Wait, the MTA had existing pumps? What happened to them?Q: Wait, the MTA had existing pumps? What happened to them?
Well, as we said, the water damaged them pretty bad but aside from that, they were really (really) old. Before Gizmodo's site crashed last week (Sandy drowned all of Gawker's servers) it ran a great piece (here's a cache of the site) on how vulnerable the MTA's tunnels are to flooding. The piece included insightful nuggets, noting that some of the pumps were bought secondhand from the builders of the Panama Canal. And that on any given day (sunny, no rain) it pulls 13m gallons of water out of the subway. And that back in the 1990s, the MTA had to send scuba divers to fix a broken water main that flooded the station at 125th Street and St Nicholas Avenue.Well, as we said, the water damaged them pretty bad but aside from that, they were really (really) old. Before Gizmodo's site crashed last week (Sandy drowned all of Gawker's servers) it ran a great piece (here's a cache of the site) on how vulnerable the MTA's tunnels are to flooding. The piece included insightful nuggets, noting that some of the pumps were bought secondhand from the builders of the Panama Canal. And that on any given day (sunny, no rain) it pulls 13m gallons of water out of the subway. And that back in the 1990s, the MTA had to send scuba divers to fix a broken water main that flooded the station at 125th Street and St Nicholas Avenue.
Q: Can we assume that after the water is out of the tunnels, that service will resume as usual?Q: Can we assume that after the water is out of the tunnels, that service will resume as usual?
Unfortunately, getting the water out is just the first step in the process. According to a recent Quartz piece, rebuilding and refurbishing the equipment that has been damaged by the water (and corroded by the salt) is a problem and finding trained personnel to do the work on the ancient equipment won't be easy.Unfortunately, getting the water out is just the first step in the process. According to a recent Quartz piece, rebuilding and refurbishing the equipment that has been damaged by the water (and corroded by the salt) is a problem and finding trained personnel to do the work on the ancient equipment won't be easy.
The Wall Street Journal noted that some of the equipment may be obsolete. Quartz said such equipment would have to be redesigned and then installed – a long process.The Wall Street Journal noted that some of the equipment may be obsolete. Quartz said such equipment would have to be redesigned and then installed – a long process.
Our editors' picks for the day's top news and commentary delivered to your inbox each morning.Our editors' picks for the day's top news and commentary delivered to your inbox each morning.
Our editors' picks for the day's top news and commentary delivered to your inbox each morning. Enter your email address to subscribe.
Our editors' picks for the day's top news and commentary delivered to your inbox every weekday.