Repair crews are racing to complete repairs on the break, which has shut down the air conditioning inside the sweltering transit hub.
As a result of the break, the cold-water supply to the AC units in Penn Station was shut off. Commuters were fanning themselves in the steamy and sweaty underground station.
The problem began with flooding inside of 250 West 34th Street between 7th and 8th avenues.
The FDNY reported as much as four inches of water in that basement at one time as they continued to pump out the water. Con Edison has shut down the steam to the block, which had an impact on the CitiBank located on the corner.
The 34th Street entrance to the Nos. 1, 2 and 3 subway lines was closed, as was the entrance to the Long Island Rail Road, but both reopened around 5:30 a.m.
One lane of traffic in each direction on 34th Street opened around 6:45 a.m. after the block was completely shut down to traffic, and regular traffic has since resumed.
Bus service on the M34 and M34A routes was also being re-routed before buses resumed running around 6 a.m. Operations inside Penn Station were not disrupted, and subway service was not affected.
"We used a hydraulic pump, pumped out some of the water," an FDNY official said. "DEP got here pretty quick. They looked at their charts and maps. They figured out where the isolation valves are. They shut it down, and it stopped the leak. And we were able to work with Con Ed to make sure that the building was safe."
Crews are still working underground on the repairs.
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