The MTA just posted images of subway signaling equipment that was damaged when Hurricane Sandy caused the ocean to invade the New York City underground. This relay from the Rector Street station spent three days under water.
Salt water in the subway is is incredibly dangerous because it causes severe corrosion very quickly. Compare the new relay on the right to the mess on the left:
Considering how much of the subway was under water, it's impressive that the MTA has been able to get the system up and running to basically full capacity so quickly. [Flickr]
Images via Deirdre Parker/ Metropolitan Transportation Authority