New York City Stinks

Well, at least people over a wide area are saying they smell gas.

"The smell is there. We don't know the source of it," said New York City Mayor Michael Bloomberg in his daily news conference.

But Bloomberg said the levels of natural gas around the city were not dangerous, according to sensors.

The Port Authority said it believes the gas leak is coming from Bleecker Street.

Law enforcement sources told WNBC.com that this does not appear to be an act of terror.

"It is still early but there is no indication of terrorism and there is no credible intelligence to suggest any imminent threat to the homeland or to New York at this time," said Russ Knocke, spokesman for the Department of Homeland Security.

He said the agency is closely monitoring the situation and talking with the local authorities, who are the lead in the matter.

Having seen something like this before, let me make an educated guess. Natural gas does not have an odor. So to allow people to be able to tell there is natural gas present in case of a leak, utilities add an odorant to the gas. This substance is called methyl mercaptan and it stinks to high heaven. The mercaptan is added at a metering station. Quantities added are carefully calibrated so that the mercaptan will be destroyed when the natural gas is burned. I have seen the result when one of the meters stuck and far too much mercaptan was added to the gas. There was so much, that it did not get destroyed in the combustion process. Pretty soon, people all over whole sections of the city I lived in were calling and reporting gas leaks.

I'd be about willing to bet that this is exactly what is happening in New York right now.