Water Towers Are All About Water Pressure!
Looking at water towers, the natural assumption would be that they are just used to store water for cities and towns, but their purpose goes far beyond water storage. If they were used solely for storage, there would be no need to build them so high. It would make much more sense to have them at ground level. Building and maintaining a tower costs a lot of money. So, why do so many cities have water towers, and why do some not have any at all?
The main purpose of water towers is to pressurize water for distribution. In a sense, the towers store both water and energy. The pressure of the water when it reaches a house is very important. Increased water pressure can lead to unneeded costs in transporting water and damage to the pipes carrying the water. Lower water pressure inconveniences the end user and can cause contaminants to collect in the water. Well-flowing water is tantamount to keeping water clean. Read this article to learn about the importance of cleaning water bottles.
Pumps and water towers work in tandem to deliver consistent water pressure to people throughout the day. A pump is a device that displaces fluids by changing pressure in the connected pipes. Pumps need electrical energy to change pressure and function properly. Some cities rely only on pumps to deliver water, but there are a few problems with relying solely on pumps for proper water pressure. The changing demand for water throughout the day leads to constant changes in the water output of the pumps. Average water usage changes throughout the day. It is highest in the morning and afternoon and lowest at night when people are asleep. It is even higher in cases with unexpected levels of water demands, like a fire.
The water system needs to be able to handle delivering the proper water pressure to all homes at all times of the day. Regular water pressure can vary from 30 psi to 85 psi. Using pumps alone to send the water to all buildings wastes a lot of energy. The pumps then also need to be designed to push the maximum of water, adding to costs. The further away a home is from the water source, the more energy must be exerted for it to reach its destination at proper pressure levels.
Water towers are used to store water, and then distribute it as needed. Water towers reduce the amount of pumps needed to distribute water and help keep water pressure constant throughout the whole neighborhood they serve and for the whole day. Water towers are able to accomplish this task with the help of gravity. A pump is used to push thousands of gallons of water up into the water tower. The water in the tower then naturally wants to go back down from a place of high pressure to a place of low pressure (because of gravity). Moving the water out of the water tower and into homes then becomes a task requiring minimal amount of extra pumps and pressure control. The water in the tank is used to supply the area for a whole day.
Water towers help minimize all the problems presented by a purely pipe and pump system. First, water towers reduce energy consumption and cost by activating pumps during the off-hours to refill the water tank. Electricity is less expensive during the off hours (usually the night time). Systems that rely solely on pumps use the most energy during the highest levels of water consumption, which then puts a strain on the electrical grid as well. Also, since the water companies are paying higher costs for water, these costs will likely be pushed on to the end consumer as well.
As mentioned earlier, water towers also reduce the problems with water pressure. Water towers are filled each day with thousands, or even millions of gallons each day. Much of the water supply is used throughout the day, and then refilled at night. The presence of water in the tank means there is always water nearby to be used. The stored water also means that water pressure will not decrease much in the case of a power outage. Since the water is already high, gravity naturally wants to push it down and into people’s homes.
Why Don’t All Towns and Cities Have Water Towers?
Despite all the benefits to water towers, there are still many costs. Building a water tower and tank costs a lot of money so does maintaining it. Smaller towns may find it cheaper to simply use pumps to push water to homes, especially in smaller towns with lower water demands. Other towns may simply not have the resources to add a water tower. Some cities require buildings to have their own water tanks as well. This is often the case with large cities with skyscrapers. Thinking back to the benefits of water towers, we remember that they are made to use gravity to push water to homes. When the buildings are higher than the water tower itself, this idea falls apart. Instead often time, buildings will have their own pump systems or water tanks.
If you want to learn more about the history of water towers, read the Wikipedia page.