Con Edison’s Own Bad Repairs at Fault in Con Edison Steam Pipe Explosion, Report SaysDec 27, 2007 | Parker Waichman LLP Last summer’s Con Edison Steam Pipe Explosion in New York City was the result of shoddy repairs performed by the utility company. A clump of sealant probably caused the deadly July 18th steam pipe explosion in midtown Manhattan, Consolidated Edison, said. Con Ed spokesman Michael Clendenin said Wednesday that the clog came from epoxy resin injected into the pipe four months before the blast. The epoxy sealed a flange, or seam, connecting two segments of steel pipe and some epoxy got into a valve, leading to a buildup of pressure that ruptured the pipe. The condition, known as "water hammer," can result when water condenses in a closed section of pipe; the sudden mix of hot steam and cool water can make pressure surge. The findings drew a scathing response Thursday from City Councilman and Con Ed critic Eric Gioia, who noted the utility pointed at the city as potentially responsible for the blast.
In October Con Ed blamed city sewers, pipes and drains for leaking cold water onto the hot steam pipe and filed a $25 million notice of claim—the first step toward a lawsuit—against the city. "They'll do anything they can to deflect blame and avoid taking responsibility," Gioia said. "But now this report shows that Con Ed's poor maintenance contributed to this deadly explosion." There have been over a dozen steam pipe explosions in the city in the last 20 years.
The explosion occurred just before the 6 p.m. rush hour beneath a street near Grand Central Terminal—near 41st Street and Lexington Avenue—and shot a large, hot, rank stream of brownish steam several stories high, sending panicked workers and residents running. The cloud contained mud, rust-colored slime, and pieces of pavement. Officials reported one death and over 30 injuries, two of them critical; three firefighters and one police officer were among the injured. One woman died of a heart attack while fleeing and two in a tow truck that was thrown into the air and landed in the crater left by the explosion were badly burned.
Debris slammed into nearby skyscrapers before it showered down on the streets for over two hours, raising concerns about asbestos—a known carcinogen for which most health officials say there is no safe exposure level—which was used when the pipe was laid in 1924. Michael S. Clendenin, a spokesman for the utility, said tests would be conducted for asbestos. “We always assume there’s asbestos in a steam pipe,” he said, “so we are treating these materials sent up by the rupture, including piping, as if asbestos were in them.” Within hours, Con Ed and the city’s Department of Environmental Protection took air and debris samples and subway entrances and exits were scheduled for testing.
Con Ed replaced all 1,654 similar valves in the steam system, finding no other epoxy clogs, Clendenin said adding that the utility was changing rules for fixing flange leaks. "We're learning from it, and we're taking corrective actions," he said of the findings. A lawyer for the tow-truck victims was leery of the utility's reassurances that no similar danger lurked. "Are we supposed to take Con Ed's word for it?" attorney Kenneth Thompson said.