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Drinking water comes from a variety of sources including public water systems, private wells, or bottled water. Ensuring safe and healthy drinking water may be as simple as turning on the tap from an EPA-regulated public water system. Other water sources may need a water filter, a check on water fluoridation, or an inspection to ensure a septic tank is not too close to a private well. It is important to know where drinking water comes from, how it’s been treated, and if it's safe to drink.
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Quality & Testing, Regulations, Sources, Treatment...
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Wells (Basics, Testing, Treatment), Nonpublic Water Sources...
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Drinking Water Fast Facts
Regulations
- All public water systems in the U.S. are required to follow the standards and regulations set by the U.S. Environmental Protection Agency (EPA).
- EPA regulations that protect public water systems do not apply to privately owned wells or other individual water systems. Owners of private wells are responsible for ensuring that their well water is safe from contaminants.
Prevention
- The impact of clean water technologies on public health in the U.S is estimated to have had a rate of return of 23 to 1 for investments in water filtration and chlorination during the first half of the 20th century 4.
- Community water fluoridation prevents tooth decay safely and effectively. Water fluoridation has been named one of 10 great public health achievements of the 20th century 5.
Drinking Water Systems
There are two types of drinking water systems in the United States. They are:
- Public water systems that are subject to United States Environmental Protection Agency (EPA) regulations.
- Individual water systems that are not subject to EPA regulations.
According to the EPA, approximately 286 million Americans receive their tap water from a community water system. These public water systems are monitored and regulated as set by the EPA.
An estimated 15% of Americans, or about 45 million people, get their water from private ground water wells that are not subject to EPA regulations. Private ground water wells can provide safe, clean water. However, well water can also become contaminated, leading to illness. It is the responsibility of well owners to maintain and treat their well 1,2,3.
- U.S. Environmental Protection Agency. Factoids: drinking water and ground water statistics for 2007.
- U.S. Environmental Protection Agency. Private Drinking Water Wells.
- U.S. Census Bureau. National and State Population Estimates.
- Cutler, D., G. Miller, 2004. The role of public health improvements in health advances: the 20th century United States. [PDF - 50 pages] National Bureau of Economic Research. Working Paper 10511. Cambridge, MA, USA.
- CDC. Achievements in public health, 1900-1999: Fluoridation of drinking water to prevent dental caries. MMWR Morb Mortal Wkly Rep. 1999;48:933-40.
*1971-2010; Ordered from highest to lowest frequency (i.e., #1 is the most-commonly reported etiology). Calculations include etiologic agents from outbreaks with multiple etiologies. Includes historic legionellosis outbreaks reported in the 2007-2008 data summary.
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Top Causes of Drinking Water Outbreaks
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For a complete listing of water-related surveillance data, see CDC's Surveillance Reports for Drinking Water-associated Disease & Outbreaks.