Water Quality & Testing
The United States has one of the safest water supplies in the world. If you are among the 286 million Americans that get their water from a community water system (1), your tap water is regulated by the United States Environmental Protection Agency (EPA).
Drinking water varies from place to place, depending on the condition of the source water from which it is drawn and the treatment it receives, but it must meet EPA regulations.
Even though our tap water supplies are considered to be one of the safest in the world, water contamination can still occur. There are many sources of contamination, including:
- Sewage releases
- Naturally occurring chemicals and minerals (for example, arsenic, radon, uranium)
- Local land use practices (for example, fertilizers, pesticides, livestock, concentrated feeding operations)
- Manufacturing processes (for example, heavy metals, cyanide)
- Malfunctioning on-site wastewater treatment systems (for example, septic systems)
In addition, drinking water that is not properly treated or which travels through an improperly maintained distribution system (for example, the piping system) may also create an environment for contamination.
The presence of certain contaminants in our water can lead to health issues, including gastrointestinal illness, reproductive problems, and neurological disorders. Infants, young children, pregnant women, the elderly, and immunocompromised persons may be especially susceptible to illness.
The EPA sets standards and regulations for the presence and levels of over 90 different contaminants in public drinking water, including E.coli, Salmonella, Cryptosporidium, metals such as lead, and disinfection by-products. For more information on these contaminants and maximum contaminant levels, please visit EPA's Drinking Water Contaminants page.
If you are getting your water from a private ground water well, and are looking for information related to wellwater quality, please visit CDC’s Private Wells page
Consumer Confidence Reports
Every community water supplier must provide an annual report, sometimes called a Consumer Confidence Report, or "CCR," to its customers. The report provides information on your local drinking water quality, including the water's source, contaminants found in the water, and how consumers can get involved in protecting drinking water.
- View the CDC's guide to Understanding Consumer Confidence Reports
- See if your CCR is posted online (United States Environmental Protection Agency Local Drinking Water Information)
- Environmental Protection Agency. Factoids: drinking water and ground water statistics for 2007. March 2008, April 2008. Available at http://www.epa.gov/safewater/data/getdata.html.
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