The Primary Function Of Water Towers Is…..to pump Water !

 

I didn’t know this. All these years I used to look up at water towers and say “Why did they have to build them that tall ?” Here in India, water towers are used primarily as…landmarks ! The Koramangala water tank is well known, then there is the Sankey water tank. But today I learned that the reason of building the water reservoir on a tower is to let gravity act on it, and the water pressure thus created will let the water rise up into higher floors in buildings. Look at the diagram:

At first glance, it would be easy to assume that water towers exist to store water. They are, after all, giant above ground vessels filled with anywhere from tens of thousands to millions of gallons of water.

But whether you’re talking about a modest little water tower perched atop an apartment building in New York City or a giant municipal water tower, water storage is not the primary function of the tower (if water storage was the only goal, it would be significantly cheaper to build a reservoir). The primary function of water towers is to pressurize water for distribution. Elevating the water high above the pipes that distribute it throughout the surrounding building or community ensures that hydrostatic pressure, driven by gravity, forces the water down and through the system.

The design helps keep the cost of water distribution lower for two reasons. First, it allows for centralization of pumping and pressurization, and decreases the number of pumping stations needed in the vicinity of the water tower. Second, it allows the water company to pump water up to the tower during off-peak energy times to decrease the expense of running the pumps.