The tanks hold water for the fire sprinkler system.
Bruce,
Roof top water tanks were filled from the center. The line You see is the outlet: Read info and diagrams:
http://untappedcities.com/2013/07/18/cities-101-how-do-water-tanks-work/
Take Care!
Frank
That one pipe probably housed both the supply line and the exit pipe. They may have been encased in a single insulated pipe to protect them from freezing. Here's a pic showing a similar tank. It looks like only one pipe beneath it.
http://images.fineartamerica.com/images-medium-large-5/new-york-water-tower-16-gary-heller.jpg
Steve S
I have built the Walthers cornerstone "reliable warehouse" kit and I wonder what the cylindrical, cone shaped roof, tank is supposed to be for. I presume a water tank but, if so, how come it only has one pipe running from the bottom of the tank down to the roof?
73
Bruce in the Peg