LONG before Hurricane Katrina’s flood waters receded from New Orleans, the “I told you so’s” – about the years of warnings of a coming killer storm – surged in.
Well, here’s a warning about New York City. Not that it’s on the verge of being destroyed by anything like Katrina, but one that’s worrisome enough.
The threat is steam. Specifically, the 10 million pounds pumped beneath Gotham’s streets each hour.
What would happen if New York’s steam system went down? In winter?
It could mean no heat for tens of thousands of New Yorkers and businesses. Pipes in steam-dependent buildings might freeze, and break. As the system restarted, a rupture in the network could even lead to a geyser (or several) of superheated steam venting up through the street. Maybe even an explosion.
The economic fallout could be hefty, as well – as tenants were evacuated and businesses were unable to operate.
Far-fetched? Maybe.
But credible enough to worry at least one highly regarded official: former CIA Director Jim Woolsey, now a consultant with Booz Allen Hamilton on energy and security issues.
ACTUALLY, no one can re ally be sure about what would happen in the event of a prolonged steam outage in freezing weather. Indeed, for decades, hardly anyone gave much thought at all to a shutdown. And for good reason: It had never happened before.
Then it did – on Aug. 14, 2003, the day of the big blackout that darkened much of the Northeast.
Though Gotham’s electric power was fully up and running within 30 hours, some steam customers didn’t see service return until Aug. 18.
Luckily, it was summer time. Folks sweated without air-conditioning, and some steam-dependent cooling systems may have been out for the full four days.
But no one froze to death.
Nor did frozen pipes – or other vulnerable equipment in the steam network – crack.
And trigger explosions.
Could that happen on a system-wide basis, setting off a massive, citywide catastrophe?
Probably not. Con Ed, which runs the steam system, would keep it switched off until it was sure it could be restarted safely.
Indeed, careful inspections were a chief reason it took four days to restore full service in ’03. But, again, that was summer.
In winter, it could take longer.
“It could be months” before the system was fully back up, one local expert with a top infrastructure-design firm, told me.
Meanwhile, where would those who worked or lived in affected buildings go?
WHAT would happen to buildings left unheated in the cold for long?
Jens Overgaard, who works with steam systems in Europe, said much of the city’s infrastructure would be at risk of freezing, and that its steam supply could be “strangled.”
While he hasn’t studied New York’s situation in depth, he is “mightily surprised” that “New York lacks alternative sources of steam,” as is common in Europe, to help stave off major problems.
And if the outage dragged on, how would the economy fare? Would tenants in affected buildings continue to pay rent? Would the financial district – or key commercial players elsewhere – be hit?
New York’s steam system is the largest in the world, with 105 miles of mains and pipes and 3,000 steam manholes. The network serves more than 100,000 commercial and residential establishments in Manhattan from the Battery to 96th Street – including such high-profile customers as the United Nations, the Metropolitan Museum of Art, the Empire State Building and St. Vincent’s Hospital.
New Yorkers depend on steam for a variety of reasons – heat, hot water, air-conditioning. Suffice to say, even a short winter-time shutdown would not be pleasant.
The chief problem is how to turn the system back on. Flip a switch too soon, send 10 million pounds per hour of heated, pressurized steam coursing furiously beneath the city’s surface – and you risk major catastrophe.
ANY significant breach in the system, made more likely by the cold, could invite a rupture – and a steam geyser roaring up through the street, decimating anything (or anyone) in its path.
A second risk: water- hammer.
Ever hear knocking in a pipe or radiator?
That’s water-hammer.
In the large underground mains, the knocking could be several orders of magnitude worse. It wouldn’t be a knock – but a monstrous BAM!
Just as it was in Gramercy Park in 1989. Back then, a water-hammer in a 24-inch pipe triggered a killer blast that ripped through the street, opening a huge crater and sending steam, mud, debris – and asbestos – 18 stories in the air.
Three people died. Dozens were injured. Millions of dollars in property were lost.
Some evacuated residents couldn’t return for months.
What causes water-hammer? Often it’s water from condensation (a natural by-product of any steam system) fired through pipes at great pressure.
New York’s steam system contains traps, drains and pumps that remove condensation to prevent water hammer. If left in the system, though, or frozen from the cold, condensation or lingering water could be propelled with enormous force by oncoming steam as the system restarts. When the water hits a joint or a pipe fitting – kaboom!
Sensitive to this, Con Ed workers move slowly before restarting a system, inspecting for cracks, leaks and excess water. But in winter, a lengthy shutdown could allow traps, and other parts of the system above the “frost line,” to freeze and maybe break. So inspection and repair work could take days. Meanwhile, a slow restart could lead to more freezing. Any shutdown in sub-freezing temperatures “beyond a day,” one expert said, and there are “big risks.”
BUT this is all nonsense, according to Con Ed and a state official involved with oversight of the industry.
The utility’s spokesman, Mike Clendenin, says no water would remain in the system because steam users would consume it all as the system shut down. Indeed, he says that is precisely what inspections showed after the ’03 blackout.
Yet some still say that, in the cold, all bets are off.
The state official also said efforts are underway to have backup steam ready, to prevent freezing and hasten recovery.
Too little, too late, critics say.
Two years after the blackout-day shutdown, one industry official said, “nothing’s been done.”
After Katrina, doomsday scenarios proliferated – some, no doubt, needlessly alarming.
But reconsidering new dangers – like a “steam freeze” in New York – is prudent. If action is needed, officials must move quickly to fix the problem. Or be ready for the “I Told You So’s” when catastrophe strikes.
E-mail: abrodsky@nypost.com