Why in US cities does steam come out of gutters/sewers in the ground?

Question

When I watch American films, which are set in big cities such as New York or Chicago, there is always what looks like steam coming from the edge of the road, why is this?

Answer 1

It's not steam from sewers or subways - in fact it's New York's centralised steam heating system that quite a lot of buildings are connected to. See http://www.coned.com/history/steam.asp

Answer 2

Because it is extremely cold in New York and Chicago. Most of the movies that you see when they are in cities like this are captured at nighttime. Many things can warm up the road, such as driving vehicles. Also, the water in the sewer tends to be warm. And warm water, obviously, steams when it comes in contact with cold air.



But please keep in mind, TV is not everything it says it is. TV lies. =]

Answer 3

Cause under the ground the pipes and things are warmer than the surrounding air so the water evaporates after condensing on them. Plus there are steam pipes to help heat buildings. It shouldn't just be US cities you see it.

Answer 4

It only happens when its freezing out side. The sewer water is coming from buildings and houses (bath,shower,dishwasher,clothes washer, etc.). So the sewer water is going to be a lot warmer than the air out side when its cold, then you get steam.

Answer 5

you will find this in Cities that have colder weather the steam is from warm air coming out of the subway meeting the cold winter air at street level

Answer 6

Steam is invisible. What you see is water vapour caused when steam meets cooler air and condenses. Underground pipes are warmer than the cold winter air so you get water vapour rising out of the grates.

Answer 7

because there are steam lines that run under ground in some locations. other places, there are hot discharges to the sewer lines

Answer 8

New Yok has it because ppl that make fast hot dogs and polutes the air make the sewars moldy with frezzing or burning weather.

Answer 9

hot liquids in drain warmer than the air which makes gases visible

Answer 10

They keep the boiling A rabs down there.

Answer 11

They're a fat bunch, the yanks, and their shite's copious, hot, greasy and steamy...eeurgh, what a horrible mental image! Yuk!