Steam rising in New York

The bulk of steam rising from manhole covers is actually sewer water being boiled by the heat of the pipes not by cracks in the pipes themselves.

Yes, i have discovered that power companies no longer use steam as a city heating system. It was ceased in 1984. The steam now seen from the pipes and manholes is as the last person noted is from the sewer water boiling up. This is monitored by the city council and often released to aviod pressure build up.

Revo, you are somewhat correct. The NYC steam plant actually stopped running fully in 1985. The large orange and white chimneys are whenever ConEd or some other utility group goes in to do work, they often have to avert/redirect/vent off the excess steam so they can get access to (or bypass) whatever it is theyre working on. The steam seen comming from the streets today is condensation from the sewer and storm water channels below.

But why are the sewer pipes hot!?

All these responses are wrong. ConEd does generate steam, and NYC has the largest steam generation system in the world with over 1800 customers from the southern tip of manhattan all the way to 96th street. There are actually 5 steam plants in Manhattan, and one in Brooklyn and Queens. They work together to generate. There is no "main" system.

The steam vapor is caused by water falling on a steam pipe, or a manhole cover or due to a steam leak

Yes, there are 1800 steam accounts in Manhattan.  If you are one of them, or if you know of one of them, please have them go to http://utility-bill-audit.com for a review of their historical usage.
Steam accounts are usually rather large and they do not bill like gas and electric does.  They are prone to meters breaking down from the intense heat and subject to errors.

This makes them a prime candidate for refunds.  We are one of the few utility auditing companies (Utility Refund Solutions)  that know how to audit steam accounts and get refunds back.