Where Does Drinking Water Come From?

For most of us, we may not give much thought to the water that comes out of our tap or the filtered dispenser in the refrigerator. We’ve grown up with it and take for granted that it will be there and drinkable whenever we need it. But if you’ve ever received a boil-water advisory, then you know how inconvenient it can be to not trust your water source. You may not have noticed how often or how much you rely upon safe, clean water in order to complete everyday tasks.      

It’s estimated that each person needs between 20 and 50 liters of water per day for hygiene, cleaning, cooking, drinking and more. That’s a lot of water that needs to be tapped, treated and dispersed. So, where does drinking water come from in U.S.? In this article we’ll delve into that question and what has to happen for clean water to get to you.

Where Does Drinking Water Come From?

There are generally considered to be two types of drinking water: groundwater and surface water. 

Groundwater collects in underground pockets of rock called aquifers, which can be tapped and transported to cities and neighborhoods through water treatment systems and networks of pipes. It can also bubble to the surface at certain points to create springs. Many companies that sell bottled water use springs as sources. 

In some areas, like Texas and the western states, the groundwater can be brackish, saturated with salt, and require desalination treatment before it can be considered safe to drink. Some coastal communities use desalination plants to convert seawater to drinkable water, but this practice produces concentrated saltwater called brine that could have a negative impact on the surrounding environment. 

Two-thirds of the water we drink comes from rivers and streams, according to the nonprofit organization American Rivers. Major cities like Seattle and New York depend on fresh water sources like the Cedar River and the Delaware River Basin for clean water. Minnesota’s Twin Cities get their water from the Mississippi River. The EPA’s online drinking water map can tell you where the water in your community comes from and help you find out how safe it is. 

How is Drinking Water Treated?

Before water gets to us, it must first be treated to remove microorganisms and other contaminants. Community water sources go through four main stages of treatment on their way to us: coagulation and flocculation, sedimentation, filtration and disinfection.

  1. Coagulation and Flocculation: During the coagulation and flocculation phase, chemicals with a positive charge are added to the water, neutralizing the negative charge of the dirt and pollutants present. That allows the chemicals to bind with those foreign elements, forming a sediment called floc. 
  2. Sedimentation: The sediment formed during the flocculation process gathers mass and settles to the bottom of the water supply. This allows the now clear water on top to pass on to the next phase. 
  3. Filtration: During filtration, the clear water passes through filters of various constructions and sizes. The ones most often used are sand, gravel and charcoal. The varying pore sizes of the filters catch dissolved particles like dust and microorganisms that could still be present. 
  4. Disinfection: Finally, a disinfectant like chlorine or chloramine is added to the water to kill any remaining parasites, bacteria or viruses that could be present. Fluoride is also added to the water to prevent tooth decay. After that, the treated water is stored until it is sent through pipes to be available at the turn of a tap. 

Despite the water now being treated and considered safe to drink, those pipes could still pose a problem. Older pipes can be made of lead or have lead fittings, and that metal can seep into the water supply and create extremely unhealthy levels of lead in the water. To combat problems like this, pipes can be replaced completely or treated with a phosphate, which forms a barrier between the water and the pipe. Researchers in California are currently working on a new process that uses an electrical current to create a protective layer on the insides of lead pipes.

The steps communities take to ensure proper water treatment and distribution vary and several factors come into play. Areas relying on well water have different priorities than those drawing from large water treatment plants. Behind every policy is a leader trained on the complex issues surrounding water. Earning a water resources master’s degree online will prepare you for a leadership position within federal and state environmental agencies, environmental non-governmental organizations, international development agencies and environmental consulting firms. East Central University’s online M.S. Water Resource Policy and Management trains students for leadership roles that make water policy decisions that impact various communities. Our program integrates knowledge from multiple disciplines to address the complex challenges of water resource decisions and to develop solutions that are socially acceptable, politically and economically viable and environmentally sustainable. Because our program is fully online, you’ll be able to earn your degree on a schedule that works for you.