What Happens When You Flush a Toilet in New York City

Jack Coyne of Public Opinion sought to learn what happens when a toilet is flushed within the five boroughs of New York City. To do so, he garnered the expertise of those who work in the field.

This is a story about the people behind the New York city sewer system

He spoke with plumber Mike Romero, archivist Ian Fowler of the NY Public Library, Newtown Creek plant chief Stephen Cubero of the NYC Department of Environmental Protection (DEP), and DEP Commissioner Rohit Aggarwala, all of whom gave a complete look into the lengthy sewage process.

So when you flush a toilet in New York City,,the sewer line will bring it into one of our 14-way sweater treatment plants around New York City. O course the sewer’s been going downhill so we’ve got to pump it up or the solids will settle to the bottom. Oil will be skimmed off the top. The wastewater will be reprocessed. That wastewater will then spend time in a aeration facility where you’ve got bugs, basically bacteria like you might have in a swamp or even in your stomach, that are going to eat the organic material that’s in there and then the solids get digested.

They also explain that the wastewater does not reach the East River until it has been thoroughly cleaned and disinfected.

After all the waste is removed, it’s going to make its way into our disinfection process. We use the chemical sodium hypochlorite. So that’s basically bleach, then depending on how much chlorine there is we’re going to deactivate that with another chemical called sodium bisulfite to neutralize it. This way it’s compatible with the water in the East River. We’re not affecting any of the marine life. By the time it reaches the outfall, it’s clear as day.