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Notice to Readers: National Drinking Water Week --- May 3--9, 2009

Water plays a critical role in the success of a society, from meeting basic public health needs to supporting agricultural and other economic activities. Worldwide, approximately 1.1 billion persons do not have access to an improved water supply, and 2.6 billion (nearly half of the developing world) lack access to adequate sanitation (1,2). This year, May 3--9 is National Drinking Water Week, which highlights the critical importance of safe drinking water to protect public health.

Although the United States has one of the safest public drinking water supplies in the world (3), sources of drinking water can become contaminated through naturally occurring chemicals and minerals (e.g., arsenic), local land use practices (e.g., pesticides), malfunctioning wastewater treatment systems (e.g., sewer overflows), and other sources. The presence of contaminants in water can lead to adverse health effects, including gastrointestinal illness, reproductive problems, and neurologic disorders.

Approximately 15 million U.S. households obtain their drinking water from private wells, which are not covered by federal regulations protecting public drinking water systems (4). Owners of private wells are responsible for ensuring that their water is safe from contaminants. Additional information about protecting private groundwater wells is available at

National Drinking Water Week is a time to recognize the importance of safe drinking water. New challenges, such as aging drinking water infrastructure, climate change, chemical contamination, increased drought, and the emergence of new water supply paradigms (e.g., water reuse), will require continued vigilance to protect the water supply.


  1. United Nations Department of Economic and Social Affairs. International year of sanitation: sanitation is vital for human health. Available at
  2. World Health Organization. Water sanitation and health: health through safe drinking water and basic sanitation. Available at
  3. US Environmental Protection Agency. Drinking water and health: what you need to know. Available at
  4. US Census Bureau. American housing survey for the United States: 2007. Current housing reports. Series H150/07. Washington, DC: US Government Printing Office; 2008:20401. Available at

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Date last reviewed: 4/30/2009


Safer, Healthier People

Morbidity and Mortality Weekly Report
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