The Structure of Water Infrastructure

Much like a person taking a long, arduous journey, the fresh water in our taps must take an extended journey of its own to get to our homes. This trip includes three basic segments: where the water starts, its source; the phases of water treatment; and then (the final leg) the pipes it must cross to get to our doors. During this journey, water is exposed to many other substances, some of which, sadly, decide to go along for the ride. A few of those stowaway substances go for the whole ride, because water treatment doesn’t capture 100 percent of the contaminants that can get into our waters.

If this throws you into a panic over what substances you may be drinking, rest assured that understanding how our water delivery systems work can go a long way toward feeling like you have some control over that life-giving substance that flows through your tap. So, let’s go on a journey of our own now to learn the basics of where our water comes from, how it gets treated, and how it comes to our doors (or rather, kitchens and bathrooms).

The second most used water source is groundwater which sits underground in large aquifers, getting pumped out through wells. In both instances, the water is then taken to a water treatment plant.

Before it comes into our homes, water passes through many substances and channels, leaving it open to contamination from multiple sources — most of them before the water reaches a treatment plant, some after, and a few even during. The Water Education Foundation explains that the various materials water may pass through can contain, “sulfur, zinc, or arsenic-laden formations. Groundwater can pick up contamination from fertilizers, septic tanks, mine drainage, and naturally occurring elements, industrial chemicals and metals such as arsenic and chromium.” As if that weren’t enough, they also point out that rivers and streams are more likely than, say, an underground aquifer, to have microorganisms that can cause disease. That’s why water must go through a middle journey before it gets to the public, and that middle journey is the water treatment plant.

Next, the water is disinfected to kill pathogens that it may contain, and this is where a lot of chemicals get added into the water in order to clean it. It sounds counterintuitive, but adding chlorine and chloramine (the two most used for disinfection) kills many of the microorganisms and other toxins that can get into water, such as parasites and viruses.

Once it’s processed, that water is delivered to the city system. If you’d like to learn the particular treatment process in your local municipality, most utilities share their water treatment process with the public. For the intrepid types, there’s a great listing of every water treatment plant in the U.S. where it’s possible to learn more about your local water treatment and its processes.

Unfortunately, however, there are some things that water treatment filtering and disinfection have a little more trouble in banishing from our water, and they’re things that we’re adding into the system every day ourselves.



As an increasing number of Americans take pharmaceuticals daily, traces of those drugs are ending up in our water supplies. In fact, the Scientific American claims that this happens through various means. In some cases, it’s because households flush extra medication down their toilet. In most instances, medications get into the water supply when the drugs that aren’t absorbed into a human’s blood stream get eliminated through urine and feces. Although we may fool ourselves that wastewater completely disappears when it leaves our homes, it’s often cleaned and reused. Unfortunately, however, while water treatment can clean and sanitize our H2O, it’s been shown to leave some drug traces behind, and that means it’s very likely to be in the water coming to our kitchen sinks.

Of course, Scientific American also points out it’s not exactly the fault of wastewater treatment plants that they can’t filter all of these pharmaceuticals. They weren’t designed to, and the numbers of drugs that the average American takes has increased far faster in recent decades than the city budgets that might allow the plants to upgrade. There’s no need to panic, as the drugs being found in water are in significantly low amounts. However, it’s the volume that has experts concerned, particularly as they aren’t sure what effects low amounts of so many drugs entering the water will have.

PFOA, PFOS, and PFAS are substances that are commonly found in non-stick cookware, pesticides, textiles, and even leather. They’re man-made chemicals that were in wide usage until the mid-2000s. The EPA required they be phased out of product manufacturing by 2015, but there are still plenty of older products remaining out there that are letting these microplastics get into our water. Harvard researchers even found that 6.5 million Americans’ water had levels of PFOA that exceeded Federally accepted levels. Which would be fine, except that those same Harvard researchers also found that exposure to trace amounts can interfere with the immune system, and greater exposure can lead to cancer, heart disease, and even possible birth defects.