Thursday, December 1, 2011
In the 19th century, NYC required that all buildings higher than six stories be equipped with a rooftop water tower. This was necessary to prevent the need for excessively high pressures at lower elevations, which could burst pipes. In modern times, the towers have become fashionable in some circles. As of 2006, the neighborhood of Tribeca requires water towers on all buildings, whether or not they are being used.
Two companies in New York build water towers, both of which are family businesses in operation since the 19th century. The original water tower builders were barrel makers who expanded their craft to meet a modern need as buildings in the city grew taller in height.
The rooftop water towers store 5,000-10,000 gallons of water until it is needed in the building below. The upper portion of water is skimmed off the top for everyday use while the water in the bottom of the tower is held in reserve to fight a fire. When the water drops below a certain level, a switch or valve activates activate a pump or open a public water line to refill the water tower.