[Archived] Access to an Improved Water Source

Caution: The data on access to an improved water source measure the percentage of the population with ready access to water for domestic purposes. Access to drinking water from an improved source does not ensure that the water is safe or adequate, as these characteristics are not tested at the time of survey. But improved drinking water technologies are more likely than those characterized as unimproved to provide safe drinking water and to prevent contact with human excreta. While information on access to an improved water source is widely used, it is extremely subjective, and such terms as "safe," "improved," "adequate," and "reasonable" may have different meanings in different countries despite official WHO definitions. Even in high-income countries, treated water may not always be safe to drink. Access to an improved water source is equated with connection to a supply system; it does not take into account variations in the quality and cost (broadly defined) of the service. National government data are self-reported and nonstandardized.