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CDC - Private Water Systems Home - Drinking Water - Healthy Water

Private Water Systems

Top Causes of Private Drinking Water Outbreaks
Top 7 Causes - Outbreaks in Individual (Private) Water Systems* (#asterisk)
Hepatitis A (/hepatitis/A/index.htm)
Giardia (/parasites/giardia/)
Campylobacter (/nczved/divisions/dfbmd/diseases/campylobacter/)
Shigella (/nczved/divisions/dfbmd/diseases/shigellosis/)
E. coli (/ecoli/index.html)
Salmonella (/salmonella/) , Cryptosporidium (/parasites/crypto/index.html) (tie)
Arsenic, (http://www.atsdr.cdc.gov/substances/toxsubstance.asp?toxid=3) Gasoline,
(http://www.atsdr.cdc.gov/substances/toxsubstance.asp?toxid=83) Nitrate,
(http://www.atsdr.cdc.gov/substances/toxsubstance.asp?toxid=258) Phenol,
(http://www.atsdr.cdc.gov/substances/toxsubstance.asp?toxid=27) Selenium,
(http://www.atsdr.cdc.gov/substances/toxsubstance.asp?toxid=28) Yersinia enterocolitica
(/nczved/divisions/dfbmd/diseases/yersinia/) (tie)
For a complete listing of water-related surveillance data, see CDC’s Surveillance Reports for
Drinking Water-associated Disease & Outbreaks (/healthywater/surveillance/drinking-surveillancereports.html) .
According to the U.S. Environmental Protection Agency (EPA), individual water systems consist of
the use of nonpublic sources and private water systems.
The use of nonpublic sources (/healthywater/drinking/private/nonpublic_sources.html) consist of
using bottled water or water from springs, streams, ponds, and shallow wells not intended for
drinking.
Private, or individual, water systems are composed of private ground water residential wells, 1/3

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CDC - Private Water Systems Home - Drinking Water - Healthy Water

Private, or individual, water systems are composed of private ground water residential wells,
cisterns, (/healthywater/drinking/private/wells/index.html) and larger private water systems that
serve more than one residence.
Private ground water wells usually supply water to an individual residence.
Private water systems are those that serve no more than 25 people at least 60 days of the
year and have no more than 15 service connections (varies by state). Each building
serviced by the same private water system is considered to be a service connection for
that system. Most private water systems use ground water wells.
Many people in the United States receive their water from private ground water wells.
EPA regulations that protect public drinking water systems do not apply to privately owned wells
or any other individual water system, such as rainwater collection.
(/healthywater/drinking/private/rainwater-collection.html) As a result, owners of individual water
systems are responsible for ensuring that their water is safe from contaminants.

Related Links
CDC
Private Well Water and Fluoride (/fluoridation/faqs/wellwater.htm)
Immunocompromised Persons and Drinking Water
(/parasites/crypto/gen_info/prevent_ic.html#drink)

U.S. Environmental Protection Agency (EPA)
Poor Water Quality and Human Health (http://www.epa.gov/safewater/privatewells/health.html)
(http://www.cdc.gov/Other/disclaimer.html)

Setting Standards for Safe Drinking Water (http://www.epa.gov/safewater/standard/setting.html)
(http://www.cdc.gov/Other/disclaimer.html)

U.S. Geological Survey (USGS)
Water Quality Information Pages (http://water.usgs.gov/owq/)
(http://www.cdc.gov/Other/disclaimer.html)

New York Department of Health
Don't Drink Water from Roadside Springs

(http://www.health.ny.gov/environmental/water/drinking/springs.htm)
(http://www.cdc.gov/Other/disclaimer.html)
*1971-2010; Ordered from highest to lowest frequency (i.e., #1 is the most-commonly reported etiology). Several etiologies
were reported only once, resulting in a 'Top 7' list. Calculations include etiologic agents from outbreaks with multiple
etiologies. Excludes outbreaks with known contamination at point of use (Deficiency 11A, etc.), unless non-POU outbreak
deficiencies were also listed. Does not include historic legionellosis outbreaks reported in the 2007-2008 data summary
due to missing drinking water system information.
Page last reviewed: June 17, 2014
Page last updated: June 17, 2014
Content source: Centers for Disease Control and Prevention
http://www.cdc.gov/healthywater/drinking/private/index.html

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Centers for Disease Control and Prevention   1600 Clifton Road Atlanta, GA 303294027, USA
800-CDC-INFO (800-232-4636) TTY: (888) 232-6348 - Contact CDC–INFO

http://www.cdc.gov/healthywater/drinking/private/index.html

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