How Do We Get Our Drinking Water In The U.S.?
Before you take a gulp of water, try to mentally trace where that water that just gushed out of your taps has been: How did it go from that weird-tasting raindrop to the clear, odorless water that is sitting in your glass now?
Safe drinking water is a privilege Americans often take for granted — until a health crisis like the one in Flint, Mich., happens that makes us think about where it comes from and how we get it.
Our drinking water comes from lakes, rivers and groundwater. For most Americans, the water then flows from intake points to a treatment plant, a storage tank, and then to our houses through various pipe systems.
Coagulation and flocculation - Chemicals are added to the water. They bind with the dirt and dissolved particles, forming larger particles called floc.
Sedimentation - The floc is heavy, so it settles to the bottom of the tank.
Filtration - The clear water on top passes through filters composed of sand, gravel and charcoal to remove dissolved particles such as dust, parasites, bacteria, viruses and chemicals.
Disinfection - Chlorine or chloramine is added to kill parasites, bacteria, viruses and germs. Fluorine is added to prevent tooth decay.
Various other chemicals can be added to adjust for hardness and pH levels or to prevent corrosion, based on the water source. But depending on where you are in the United States, there can be different challenges, and corresponding methods of treating drinking water.