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By: Tyler Gatewood on September 30th, 2020

Where Does Tap Water Come From?

We just assume our tap water is safe for consumption, but do we really know where it came from and how it was treated? In America, we take our safe drinking water for granted by not questioning how exactly it made it from its original source into the faucet. 

The United States alone consumes more than one billion glasses of tap water. Up to 60 percent of the adult human body is water, and it is the vital nutrient that keeps all of our cells and molecules functioning. Water consumption is essential for survival, with adults needing a recommended amount of between 2-3 liters of water per day.

In the United States, the majority of tap water is sourced from either lakes, rivers, or groundwater. With hundreds of thousands of rivers and lakes across the United States, this is a very broad spectrum and leaves a lot of room for variances within municipal water sources. 

While cities like Washington DC and New Orleans may get their water through local river sources, Chicago relies on Lake Michigan and New York City relies on Aqueducts from the Catskills.

At Exell, we speak with customers every day who are concerned about their municipal water source and where exactly their water comes from. We are passionate about clean and safe water, and want to make sure that you are fully informed so that you can make a decision about your water service needs.

How Is Tap Water Treated?

Once your water has been sourced, it is sent to your municipal treatment facility for processing and sanitation. This is a five-step process that ensures that the water coming out of your faucet is safe for consumption. The five steps are:


This is where chemicals, such as chlorine dioxide and aluminum sulfate, are added to the water, causing small particles to coagulate, or bind together. This is beneficial to help for removal of the larger particles in the latter part of the treatment process. 


Once the small particles bind together in the coagulation step, they are stirred together to form floc. The floc form acts as a magnet to other particulates in the water.


Once the particles are in flocc form, they are denser than water and settle to the bottom. During this process, nearly ninety percent of the solids in the water are removed. 


Finally, chlorine gas or liquid bleach is added to the water to kill microorganisms. Some common organisms found in drinking water can cause diseases such as gastroenteritis, dysentery, cholera, and giardiasis. This is also where fluoride is added to the water to promote dental health. 


Once the water has been disinfected, it is then pulled through filters to remove any remaining particles. During this process water is passed through sand or coal filters to remove anything not removed during sedimentation.

How Is Tap Water Distributed?

Once the water has been treated and passes the U.S. Environmental Protection Agency’s Safe Drinking Water Standards, it is then moved to a storage facility to await distribution. Distribution systems consist of pipes and storage facilities are crucial in providing Americans with an uninterrupted supply of safe drinking water.

One important factor in a water distribution system is water pressure. When water is stored in a high location, water pressure is increased as it descends, creating force and moving the water through the pipes and mains so that it can reach its destination. 

Water Distribution Pipes

The potential dangers with tap water rarely come from the water treatment plant, but rather where it goes afterwards. A common problem is the pipes that transplant the water. They are commonly made from materials that pose potential problems such as galvanized steel or iron, cement, copper, and lead. Let’s take a look at each of these materials and their potential dangers:

Galvanized Steel or Iron

Steel pipes that have been galvanized means that they have been coated with zinc to prevent rust and corrosion. Even despite their best efforts, the pipes still eventually corrode, leaving your water looking questionable. In addition to a murky appearance, the corrosion could lead to a buildup of lead, which is a dangerous toxin when consumed.

Asbestos Cement

Asbestos cement was a popular material for pipes in the first part of the twentieth century. The cement was thought to prevent erosion, however as the pipes deteriorate, asbestos is leaked into the drinking water. Asbestos has carcinogenic properties which poses a serious concern, especially because asbestos-cement pipes account for 12-15 percent of drinking water systems in the United States.


Copper is a substance that can be found naturally in all water sources, and overall it is not too concerning. The issue arises when water sits in copper pipes for long periods of time and raises the levels. For normal adults, copper is essential and it a certain amount is recommended daily, which is gotten mostly from food. This means an elevated level in your drinking water could elevate the copper you are consuming causing unpleasant gastrointestinal symptoms, and eventually liver damage.


If you’ve followed the tragedy in Flint, Michigan, it is no secret that lead has no place in drinking water, but unfortunately it is still a problem that over 10 million homes in the United States continues to face.

So, is My Tap Water Safe to Drink?

Tap water in the United States follow stringent guidelines by the EPA’s Safe Drinking Water Standards, so in theory it should be perfectly safe. The reality is that these treatment and distribution systems can fail, as evidenced by the water crisis in Flint, Michigan. 

It has been determined that at least one third of Americans, particularly those in low-income, rural areas, get their water through sources that do not meet the EPA’s guidelines. For the two thirds that do meet the guidelines, that is only valid until the water leaves the treatment plant. In areas with aging distribution systems, there is no telling what contaminants are hiding in their pipes. 

To ensure safety, it is recommended that you invest in a water filtration or purification system for water that you and your family will be using to cook with or consume. At Exell, we have an expert team that can help you figure out your water service needs, starting with a site survey. Let us help you determine the best solution to ensure you and your family have access to top quality drinking water.