|Learn More: Health Effects | What’s in My Water? | Removing Contaminants||
Why should I be worried about my drinking water?
Tap water generally comes from two primary sources: either from a municipal facility or from a private well or pond. Municipal facilities provide water for many homes and businesses and are required to meet certain federal standards by the EPA. Municipalities are required to test water at the treatment plant for certain dangerous contaminants, but as long as the water is below the maximum contaminant levels issued by the EPA, they can still deliver water to their customers. (For more information on these levels see this pdf from the EPA.) These levels may still be harmful, especially to compromised immune systems, the elderly, or pregnant women. Some contaminants may be so new that federal contaminant guidelines have yet to be issued; one of these is the cancer-causing Chromium 6 (commonly known as the Erin Brockovich contaminant). Also, municipalities may not catch leaks in pipes or older systems that could fail, which can lead to water with higher contaminant levels arriving at your tap. These leaks generally lead to a boil alert being issued to the public. Even though water leaving the municipal water facility may be relatively clean, contaminants in large distribution pipes or even in household plumbing can be introduced into the tap water. A recent article by the NY Times stated that often when researchers test water, they find that the water has more contaminants after entering the home or place of business than it does when leaving the municipal facility. A second source of tap water comes from private wells and ponds. These sources are not regulated by local or federal governments in any way. The owner of the source of water is responsible for the quality of the water issuing out of the well or pond. As seen in the illustration above, there can be many sources that can cause contaminants to leak into groundwater, and then enter the well. These can include nitrates from fertilizer used on farms, sewage overflow from local flooding, and even chemical leaks from manufacturing.
Each contaminant is caused by a different source. Pesticides may be in your water because of agricultural run-off. E. coli and other bacteria found in fecal matter may seep into your well if a neighbor’s sewage tank is leaking. Just as each contaminant may have a different source, each one can have different health effects. Chlorine, a common disinfectant, can cause skin rashes. Low levels of arsenic can cause stomach problems and vomiting, but high levels have been known to cause cancer. Nitrates are known to inhibit cellular oxygen levels and can even be fatal for infants. For more information describing the health effects of each contaminant, see the individual pages below.
Depending on where you are, where your water comes from, and even what kind of building you live in, there may be many different types of contaminants in your water. If you have a well and live in the Midwest, you may have nitrates in your water, which can be deadly to pregnant women, and infants. Or if you live in the Northeast in an older house, your family may be exposed to lead in the water due to leaching pipes.