Before setting foot into this complex island, I would look at pictures of water towers on rooftops and think that they were some sort of extinct industrial structures on top of buildings way outside the city.
The truth is that there are thousands of them here and they have been around for some time and will continue to do so. Everyday almost 4 billion liters of fresh clean water is provided to the city of New York. The pressure that the city can give is not enough for buildings that are higher than 6 stories.
So water towers are a very pragmatic solution for this problem. Although we’ve witnessed technological advances in many mechanical systems, serving water to high buildings hasn’t changed since the 19th century. And in fact, there is no reason to. Many of those tanks are made of wood which are perfect because of this thermal properties that prevents very big thermal amplitudes. I guess that’s what they say: if it ain’t broke, don’t try to fix it. And especially in this city, if it was, there would be already someone around it.