Water

Despite these limitations, the above-mentioned definition of an "improved" sources is used to measure the achievement of the Millennium Development Goal related to drinking water supply in developing countries. Access to water supply services is defined as the availability of at least 20 litres per person per day from an "improved" source within 1 kilometre of the user's dwelling.

[edit] Source

in reference to: Improved water source - Wikipedia, the free encyclopedia (view on Google Sidewiki)