After the drill, the MTA said that if New York City were hit with a storm stronger than Irene, they would likely need more men, plywood, and sandbags to keep the subway system dry. Even if they erected barriers around the perimeter of every flood-prone station in the city, wooden boards alone would not seal the entrances entirely. Perhaps they would slow the flow of incoming water, but they couldn't prevent a powerful storm surge from inundating the system. If the next storm did not peter out as it tracked north, like Irene did, the nation's largest transit system could be swamped by floodwater one station at time.
"Is the MTA prepared for a Category 1 hurricane?" John O'Grady, who led the authority's recent efforts to prepare for flooding, asked rhetorically last spring. "No, we can't be. The city itself isn't prepared."
From his spacious corner office at transit headquarters downtown, O'Grady has an unobstructed view of New York's harbor and the path that water might take to the Chambers Street subway station. An engineer by trade, he has worked for the MTA for 24 years and now manages the infrastructure and facilities arm of capital construction.
At first glance, O'Grady, a tall, resolute Irishman, appears much like any other desk-bound civil servant: rumpled suit, furrowed brow, and a few extra pounds around the middle. But the yellow neoprene boots tucked in the corner of his office tell another story. Over the past quarter century, he has spent hours in the bowels of the subway system, knee-high in what he politely refers to as "muck." Somewhere along the way, he developed an unexpected affection for the subways and now stays up nights worrying about how to keep them dry.
"The city is very vulnerable," O'Grady said. The transportation system is very vulnerable. It is in danger of being inundated by storms to the point where it becomes the ultimate sewer."
In the aftermath of Irene -- the menacing hurricane-turned-tropical-storm ironically named for the Greek goddess of peace -- city officials estimated that if the waters of New York Harbor had surged about a foot higher, they would have overwhelmed the bulwark at Battery Park and sent water cascading into Lower Manhattan. On Monday, the combined astronomical tide and storm surge did just that, fulfilling the predictions of a computer-modeling program the city uses called Sea, Lake, and Overland Surges from Hurricanes, or SLOSH for short. True to expectations, gale force winds thrust nearly 14 feet of water over the seawalls in Manhattan, and swamped coastal neighborhoods in Brooklyn, Queens, and Staten Island, too.
Slowly, water wandered out from the southern tip of Battery Park, spreading like tentacles through the Financial District and flooding streets to the east and west. Meanwhile, large swathes of Manhattan lost power, darkening the city's skyline below 39th Street. In Chelsea, a building's front façade crumbled and collapsed, its innards exposed to the storm, while a loose crane swung from atop a tall skyscraper in Midtown. Water overwhelmed two commuter tunnels connecting Manhattan to the outer boroughs -- the Brooklyn-Battery and Queens Midtown -- and flooded PATH stations linking New York to New Jersey.
"New York is riding a rail system that its grandparents put together. There's been no major reinvestment in running it."
Of course, the greatest danger of all was that water would rush down the stairwells of low-lying subway stations and pour through sidewalk ventilation grates, flooding the subway system and crippling the city's principal form of public transportation. If that happened, the authority had warned, all of the tunnels beneath the East River could be submerged within 40 minutes, and subway lines from Brooklyn to 14th Street might fill with water shortly after that.