New York Steam

[dibble1]

Where does the steam that seems to be in ample supply under the streets of New York originate from and can't it be put to good use?

[SirOracle]

From the City heating system which is underground.

[heathfield]

The steam you see on the streets rising from manhole covers, etc, is caused by leaks in the district heating steampipes, or from water coming in contact with the hot steampipes and boiling off.

[douglas9401]

Here you go.

http://en.wikipedia.org/wiki/New_York_City_steam_system