Up to 60 million people may be impacted by Hurricane Sandy this week and in the weeks to come. A hefty chunk of that population are subway-reliant New Yorkers, who would do well to read this while sitting down with a paper bag handy.

MTA PhotosMTA constructs a flood barrier last night on the tracks.

The city’s been without subway service since last night at 7 p.m., only the second shutdown in the system’s history. But how temporary is it? Gizmodo thinks this may be closer to a permanent condition.

This could be the storm that kills the New York subway system.

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From The Wall Street Journal:

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The shutdown appeared likely to last for days, officials said, and would depend on the extent of flooding and the length of time needed to restore power.

“It’s difficult to predict, but I do think Monday and Tuesday are going to be difficult days,” MTA Chairman Joseph Lhota said. “Wednesday we should have service, but whether it’s a full complement of service, it’d be very difficult for me to say now. I don’t know when this event will end and when the power issues will be corrected.”

No, no one knows. Except Mayor Bloomberg?

But this? This was hours ago.

Not worried yet? From Gizmodo:

What most people don’t know is that we depend on just 700 fragile water pumps to keep the tunnels dry—some a century old.

In fact, if someone powered down all these pumps tomorrow, the entire subway network would be inundated in just a few hours. To give you an idea of how complex and massive this system is, it pulls 13 million gallons of water out of the subway on any sunny day. No rain. Not even a single drop of water from the sky. If Sandy manages to kill the power or any of the fragile old pumps protecting the system, there may be some serious problems.

On a rainy day, the pump system is absolute chaos, to the point where the MTA—NYC’s Metropolitan Transportation Authority—lives in permanent panic, fearing events like Sandy, the hurricane system that is approaching the little town right now. “At some point, it would be too much to handle,” said the head of the hydraulics team back in 2006, Peter Velasquez Jr., “you’ve got rain plus wind. It basically would shut down the system. You hope not. You pray that it doesn’t.”

The MTA’s drainage can suck out 1.5 inches of rain per hour. Sandy’s bringing five to eight inches, plus high storm surges. And there’s only so much optimism to be gleaned from the sheer amount of sandbags the MTA appears to possess.

New York, I love you, but you’re bringing me down.