I lived and worked in the borough of Manhattan in New York City for many years, and Ii was talking to a co work in my office on 31st street between 5 and 6th avenue, just one block below the Empire State Bldg. My co worker was from Long Island where he lived, and work, now to Long Islanders, Manhattan to them was like going to another country, they rarely ventured out off the Island only if they actually commuted to Manhattan for work.
My co worker had is eyes trans fixed on a tower on a building a cross the street, and asked me what it was, and what is it for. He was dumbfounded. Yes I told him it was a water tank, and it works, and supplies water to that building. Most building taller than six stories need some type tower or pumping system to provide water pressure to tenants.
Most tanks are made of wood, because steel tank are much more expense. Most of the water tanks you see on roofs of building are 30 years old, but look much older right, because they are not painted, and not chemically treated. I think the towers are cool, great part of what makes New York, New York