Home Water Quality 101
Where Does My Home Water Come From
The average American consumes around 80 gallons of water per day, according to the U.S. Geological Survey. That’s 668 pounds. Multiplied by a population of 372.2 million, that equates to 248.6 billion pounds of water used in the U.S. every day.
It can be mind-boggling to understand how all this water gets to people’s homes, not to mention what’s in it. Fortunately, we’ve simplified the process so you can understand where your home’s water comes from.
Where Does Water Come From?
Your source of water depends on where you live. For example, many New Yorkers get their water from the Delaware River. Chicagoans rely mostly on Lake Michigan, while a farmer in Nebraska might have a private water well pumping from an aquifer.
In western states like California, some people even get water from melted snow high up in the Rocky Mountains.
At the most basic level, water comes from either a municipal source or a local well.
Municipal Water Systems
Municipal water is drawn from a large natural source, such as a lake or river, and serves thousands if not millions of people across a wide geographic area. It is a public utility which you pay for through taxes and monthly water bills.
First, the utility moves water from the source to a treatment center. Ideally, this is done through gravity (i.e. the treatment center will be at a lower elevation than the water source so the water can flow down through aqueducts and pipes). Gravity flow has been used since ancient times, and 2,000-year-old Roman aqueducts can be visited to this day.
If the water treatment center is at a higher elevation than the source, then water pumps must be used to force the water uphill.
As water flows into the treatment plant, it is fed through various stages of purification to remove harmful contaminants from the water and improve the taste and odor. These stages typically include separating scum from the water, adding chlorine to disinfect the water, and even using ultraviolet light to kill viruses.
Once the water is purified, it flows out to local pumping stations and water towers. From there, it is pumped to your neighborhood and enters your home through the main water line. While the utility handles all water pipe maintenance outside your property, you are responsible for maintaining your main water line and home piping.
Well Water Systems
A well water system taps into water underground, below bedrock. If you have a private well, then you are solely responsible for the digging, pumping, and filtration of your water and all the associated risks.
Depending on how far below the surface the water is, digging a well might involve hiring someone to come out with a rotary drilling machine. Shallower water wells come with increased risks of contamination since dirtier surface water can seep into the source. Deep wells are typically less contaminated.
Once the well is dug, you must install a pump and hire a water testing company to come out and regularly test your water for contaminants. You can also buy home water test kits, although these are far less thorough in their analysis.
Public groundwater wells operate under the same principle but are owned and operated by a public body, meaning that, for regular fees, you don’t have to do all the hard work yourself.
What’s in My Home’s Water?
Although water (H2O) typically looks the same from a distance, there is always more floating around in it than just hydrogen and oxygen molecules. There’s a good reason why municipalities take great pains to clean and filter water before sending it to your home, sometimes moving it through five or six levels of purification.
To a certain extent, contaminants are a good thing. Drinking 100% pure water (only found in the lab) would actually be bad for you because it would sap electrolytes from your body. Water contaminants are not only what give water its taste, but also its nutritional value.
However, many natural and artificial water contaminants pose a major health risk, which is why water quality is important. Ironically, after the water treatment center purifies your water, some of the cleaning additives remain in the water and form new contaminants that can make it into your tap.
Furthermore, after you use the water in your home, it goes down the drain and enters the sewage system. Eventually, some of that water makes it back to the water source (after leaving the sewage treatment plant) and reenters the water supply process.
So, just because you are on treated city water, doesn't mean it's clean or healthy for you!
The U.S. Environmental Protection Agency classifies water contaminants into four categories:
- Physical contaminants are anything you can see or touch in the water. Sediments, leaves, sewage, and plastic are all examples of physical objects contaminating the water.
- Chemical contaminants refer to natural or man-made elements or compounds like bleach, arsenic, and chlorine.
- Biological contaminants are living things in the water like bacteria, viruses, and parasites.
- Radiological contaminants are unstable elements that give off radiation such as uranium and radium.
All water will have some combination of these contaminants. Ultimately, figuring out the safety of the water you use to drink, shower, and brush your teeth with is your responsibility.