New Yorkers: What are the water tanks on your roofs all about?

-The plenty water in NY needs to be pure so they clean it up and then put it ,,,
-Cause NY has so much people
-They seem small but they are big
-i don’t think so
-in pipes
-cause the metal gets all rusty , and no i don’t get woody debris in my water
-cause it’s well fabricated
-so people don’t get all curious and open them
-no as i said they are well fabricated
-ofcourse , people who works there , to check on the water every once in a while

Because of the number of people in New York, having the water tanks on the roofs also helps having a stable water pressure at the home sink.

I like this question, I have wondered about this myself.
Water pressure would have been my first thought as to why they were needed.

They provide water pressure. The water system will only provide (consistent) pressure a few stories. Taller buildings need additional pressure, hence the water tanks.

When you see a water tower in a town. That is to provide pressure to the home.

They utilize gravity to increase the pressure, a very efficient method. Then the pump only has to work to move water into the tanks.

Having water on the roof saves money because gravity does all the work when you turn on the faucet, kind of like a syphon. I saw this on a Dirty Jobs episode. I think they replace the tanks every 10 years or so. They’re made of wood to allow for slight expansion and flexibility.

But why are they still common in New York? They are rare here in Chicago.

I think if you go to the top of the building they will still be there. Just not as exposed as the older ones.

No, I don’t think they are still there. Riding the L and commuter trains gives you a view of a lot of Chicago rooftops, and the wooden water tanks are rare. I started looking for them after seeing how common they are in NYC. The platforms where they once stood are common, but the tanks are gone.

Mike Rowe made one of these water tanks on Dirty Jobs. It was quite interesting and answered all of these questions. I know this isn’t helpful, but everything has been addressed in this thread already.

They are embedded in the roof.

They are embedded in the roof.

Agreed, metal tanks might be. I would guess they probably are. But we’re discussing the wooden tanks.

“But why are they still common in New York? They are rare here in Chicago.”
Not rare, in the building.

Question has a bit more range, then it just expressing wooden tanks.

Sorry, I assumed maybe you read the original question which mentioned tanks “like little old fashion hats (or farm silos)” and “why are they made of wood?” and “why are they on tall metal frames?”.

The original question also linked to a picture. It looked like this and this and this and this

If you might know why New York still uses those tanks by the thousands, and other cities don’t, I, like the original poster, would be interested to hear.

The East coast does things old-school since it’s cheaper to do things the same way than to redesign and retrofit. Chicago is a bit more modern so their stuff has all of the new-fangled technology from the beginning. Bear with my rambling for a moment because I do have a point here.

I get a laugh out of people on the West Coast thinking a building is old if it was built in 1920. I have lived in places with electrical wiring older than that! I’ve lived in three houses built before the Civil War about a block away from a graveyard with stones dating back to the late 1600s!

Think about it for a second; how much would it cost to replace the plaster walls and horse-hair insulation in the two-story house I grew up in to make it more heat-efficient? The owner already spent a pretty penny installing the coal-burning “octopus” heater and his son (our landlord) even more to convert it to oil.

Now multiply that out for a large building and then again for multiple buildings. Okay then, now do you see how it’s cheaper to keep the old ways around? If the building was designed with a tower, let it keep the tower.