You can turn on the faucet in your kitchen right now to wash a bowl of vegetables or fruit. We drink water, bathe in it, and cook with it. Our easy access to water makes it appear nearly limitless.
Although water comprises 70% of Earth, only one percent of water is fresh and usable. This one percent of water comes from lakes, rivers, or the ground. Your water either comes from a public source (water treatment facilities) or from a private source (wells). And this water is the result of Earth’s water cycle.
During the water cycle, water moves from one reservoir to another in a continuous motion. The sun heats bodies of water, which causes the water to evaporate. As it evaporates, it rises higher in the atmosphere, where the cold temperatures cause the water vapor to condense into clouds. Cloud particles bond to each other, condensing the vapor and causing it to fall back into the bodies of water in the form of rain, sleet, or snow. The process is then repeated again, starting with the sun warming the bodies of water and causing evaporation.
About 20% of the world’s fresh water supply comes from groundwater. Rain and snow is collected underground in a “rock pocket” called an aquifer. Soil pore spaces in the ground become saturated with water, and this maximum depth is called the water table. Groundwater rises to the surface in the form of a spring. Groundwater may also be accessed by drilling a well into the ground.
Surface water is collected from precipitation and groundwater deposits that reach the surface. in wetlands, oceans, streams, or rivers. Most surface water is not drinkable without treatment, as it comes from the salinated ocean.
For public health and safety, water is treated before it reaches your faucet. Water treatment involves the removal of impurities that make water unsafe for human consumption. This water may flow from a surface water source, or it may be pumped from an aquifer.
A public municipal water treatment system treats cities and towns and is managed by an elected official. A private water treatment system may treat a household or a small group of homes. No matter the water treatment system, the water quality standards of the U.S. Environmental Protection Agency (EPA) must be followed for a water supply that serves more than 25 people.
Chemicals and physical processes are used to filter and disinfect harmful microorganisms. While water treatment systems filter out many different impurities, they don’t necessarily filter out impurities that cause water problems such as bitter taste, foul odor, or mineral deposits.
Wells are drilled into aquifers in order to gain access to water. A pump is used for water withdrawal. Americans who rely on privately owned wells are responsible for the quality of the water pumped from the well, which means they need their own water treatment systems.
There are two main types of water delivery systems: pipes and bottled water. Both deliver drinkable water from the source to your home.
Tap water travels from a public municipal water treatment system or private well to your faucet. A series of pipes transports the water to your home plumbing. If you receive your water from a public municipal water treatment system, the water usually arrives to your household via main line from the distribution system.
Many bottled water brands are sourced from a municipal water system or a natural spring. Bottled water may undergo additional purification, as it is regulated under the guidelines of the U.S. Food and Drug Administration (USFDA).