Those large, round tanks elevated in the sky are water towers. What is a water tower and what are they used for? A water tower is a holding tank, usually for a municipality or even a farm that is used to maintain water pressure. Through the help of gravity, water puts pressure in the pipes allowing a continuous stream of water even in times of power outages. In fact before the days of electricity, water towers were used. Today they are regarded more as a backup system- and the amount in the tank is typically equivalent to a day’s use of water.
The higher the water tank is off the ground, the more pressure it exerts. While most town’s have their own water tank, commercial buildings, like skyscrapers can have their own functioning water tank to provide a smooth flow of water to the building occupants. Tall buildings without their own water tank can experience poor water pressure from a municipal source in times when water in heavy demand. If you have ever been taking a shower in the top floor of an old New York building, you’ll know how inconvenient this can be.
Pressurizing municipal tap water with a water tower has more benefits than just achieving a steady flow of water for citizens. In fact water towers can help lower the risk of pollution in a city’s water supply and act as a passive backup system that will reduce electricity demands, and thereby save money for the local government.
A water tower that maintains a pressurized water system is inadvertently warding off negative pressure scenarios. When pipes are not pressurized they are open to more problems. Negative pressure can cause the pipes to break and attract the groundwater (naturally occurring water found beneath the ground) into the water system. If groundwater is contaminated by industrial or farming pollutants, the entire city’s water system is compromised and unsafe to drink. Having a water tower around is especially important during emergencies and natural disasters, when power is out, the water system still remains passively pressurized by the gravitational pull of the water tank.
In addition to aiding in water safety for citizens and the surrounding habitat, water towers are an economical backup system. In scenarios of peak water times (usually in the summer when people are out watering their lawns) the main water pump is over-taxed. Instead of using another electrical water pump, the water tower will take over and begin supplying more water without using electricity- thus saving money and resources. During the evening when people are sleeping and not using water, the pump will refill the water tower to be used again.