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Public Water Systems FAQ

Frequently Asked Questions

Where does my drinking water come from?

Public water systems provide treated water from surface and ground water for public use. Water treatment systems are either government or privately-held facilities that withdraw water from the source, treat it, and deliver it to our homes.

What type of health issues can be related to water quality?
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 at risk for becoming ill after drinking contaminated water. For example, elevated levels of lead can cause serious health problems, especially for pregnant women and young children. Federal law requires that systems reduce certain contaminants to set levels, in order to protect human health. However, the presence of contaminants when tested does not necessarily indicate that the water poses a health risk.
The United States Environmental Protection Agency (EPA) is responsible for making sure that public water supplies within the United States are safe. In 1974, Congress passed the Safe Drinking Water Act. This law sought to protect the nation’s public drinking water supply by giving EPA authority to set the standards for drinking water quality and oversee the states, localities, and water suppliers who implement those standards. In 1986 and 1996, the law was amended to protect drinking water and its sources, which include rivers, lakes, reservoirs, springs, and ground water wells.
What contaminants should I be concerned about in my drinking water?
  • Manufacturing processes
  • Sewer overflows
Drinking water quality varies from place to place.


How often does our public water system test our drinking water?
Drinking water can be tested around the clock, including hourly, monthly, quarterly, and annually, depending on the location and size of the public water system. Certain contaminants are tested for more frequently than others, as set forth by the Safe Drinking Water Act. Compliance testing is conducted once a year, before Consumer Confidence Reports (CCR) are mailed to consumers.


What common contaminants are included in this testing?
What should I do if I want my household water tested?

How do I find out if there is a boil water or other water advisory in my community?
There are three levels of public notification, based on the seriousness of a contamination event. A Tier 1 notification pertains to the most serious and acute contamination events. Notification must be broadcast by local media within 24 hours. Tier 2 allows for a 30-day notification. Tier 3 provides notification through the annual Consumer Confidence Report (CCR). Your public water system is responsible for notifying residents if the water quality does not meet EPA or state standards or if there is a waterborne disease emergency. Depending on which tier level applies, you should be notified by the media (TV, radio), mail, or other means. For more information, see CDC's boil water advisories page.

Although chemicals (for example, bleach) are sometimes used for disinfecting small volumes of drinking water for household use, chemical disinfection is generally not recommended for commercial establishments because of the lack of on-site equipment for testing chemical residuals. Furthermore, the parasite, Cryptosporidium is poorly inactivated by chlorine or iodine disinfection. Cryptosporidium can be removed from water by filtering through a reverse osmosis filter, an "absolute one micron" filter, or a filter certified to remove Cryptosporidium under NSF International Standard #53 for either "cyst removal" or "cyst reduction." See "A Guide to Water Filters." However, unlike boiling or distilling, filtering as just described will not eliminate other potential disease-causing microorganisms, such as bacteria and viruses. Ultraviolet light treatment of water is not effective against Cryptosporidium at normally-used levels.

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    Atlanta, GA 30333
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