Photo by myself on Seventh Avenue, in Midtown.
Steam coming out of the streets is not an uncommon sight, especially when it's raining out. Billboards, too, are sometimes found outside Times Square.
Wikipedia says that NYC has an extensive steam heating system. Every so often you will come upon a makeshift smokestack sticking out of the street.
When it rains, the cold water infiltrates the streets and reaches the steam pipes below ground. The cold water hits the hot steam pipes and the resulting steam escapes through manhole covers. Walking down the street with steam billowing around, you can't help but feel like you're in a movie.
**By the way, I've wondered about why we see steam when it rains in the city, and didn't understand it til now!
For the Wiki on steam power in New York, click here.
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