Skip directly to search Skip directly to A to Z list Skip directly to site content Skip directly to page options
CDC Home

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.

Drinking Water Topics

Public Water Systems

Quality & Testing, Regulations, Sources, Treatment...

Bottled Water

Basics, Immunocompromised Individuals, Fluoride...

Water Fluoridation

Benefits, Safety, Guidelines, Fact Sheets...

Private Water Systems

Wells (Basics, Testing, Treatment), Nonpublic Water Sources...

Water & Nutrition

Health Benefits, Daily Water Needs, Weight Management...

Camping, Hiking, Travel

Safe Drinking & Recreational Water, Illness...

Drinking Water Systems

Two types of Drinking Water Systems: Public and Individual

There are two types of drinking water systems in the United States. They are:

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.

  1. U.S. Environmental Protection Agency. Factoids: drinking water and ground water statistics for 2007.
  2. U.S. Environmental Protection Agency. Private Drinking Water Wells.
  3. U.S. Census Bureau. National and State Population Estimates.
  4. 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.
  5. 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.

Contact Us:
  • Centers for Disease Control and Prevention
    1600 Clifton Rd
    Atlanta, GA 30333
  • 800-CDC-INFO
    TTY: (888) 232-6348
  • Contact CDC–INFO

Understanding CCRs

Drinking Water Advisory Communications Toolbox logo featuring water jugs The U.S. Government's Official Web PortalDepartment of Health and Human Services
Centers for Disease Control and Prevention   1600 Clifton Road Atlanta, GA 30329-4027, USA
800-CDC-INFO (800-232-4636) TTY: (888) 232-6348 - Contact CDC–INFO
A-Z Index
  1. A
  2. B
  3. C
  4. D
  5. E
  6. F
  7. G
  8. H
  9. I
  10. J
  11. K
  12. L
  13. M
  14. N
  15. O
  16. P
  17. Q
  18. R
  19. S
  20. T
  21. U
  22. V
  23. W
  24. X
  25. Y
  26. Z
  27. #