New Yorkers are used to feeling things rumble underground. It’s not usually the ground itself.
At about a quarter to 7 this morning, a 5.1-Richter earthquake hit about 15 miles south of Plattsburgh — near the Canadian border and roughly 400 miles north of here. Even at that distance, many around here claim to have felt it. Not us, even though we were (mostly) awake.
Low-grade earthquakes in the high 1s are not all that rare in the East; there’s even a noted seismological research center — the Lamont Doherty Earth Observatory in a geologically significant location just across the Hudson River from New York City. But as Californians know, 5.1 is a serious quake, and this one caused some significant road damage, though no apparent serious injury or loss of life.
I’ve been through an earthquake. One morning some years ago, I was standing in the office of the Editor-in-Chief of MacUser magazine, on the 17th floor of an office building in Foster City, California, a southern suburb of San Francisco built on landfill. He’d just offered me a job, and as we shook hands, the building did a darling little mambo. “Just the wind,” the editor said. Ummm, I don’t think so. I’ve been in office buildings in the wind, and that’s not what it felt like. When other editors started running around, it was plain that something untoward had just happened. Someone in the art department, yelled, “The scanner says 5.4!” (Why do art departments always have police scanners?) I caught the 2:10 flight home — the airport apparently didn’t even miss a beat — and didn’t take the job.
As it happens, New York is badly prepared for a significant quake. A seismic building code went into effect in 1995, but the report cited in the previous link notes that a 5.0 quake under Manhattan would cause about $660 million dollars worth of damage to property and business interruption. A 6.0 quake (10 times larger) would cause $8.8 billion of damage; a 7.0 quake — catastrophic by any measure — would cause $48 billion in property damage. From a Princeton University study titled Earthquake Loss Estimation Study for the New York City Area:
Again, although New York City is a region with low seismic hazard (infrequent damaging earthquakes), it actually has high seismic risk, which result from concentrations of buildings and infrastructure built according to no seismic codes or provisions (however, several taller buildings are designed for strong wind loads, providing resistance to horizontal loads). Considering the area龝 historic seismicity, population density, and the condition of the infrastructure and building stock, it is clear that even a moderate earthquake will have considerable consequences in terms of public safety and economic impact.