Improved water source

An improved drinking-water source is defined as one that, by nature of its construction or through active intervention, is likely to be protected from outside contamination, in particular from contamination with fecal matter.

To allow for international comparability of estimates for monitoring the Millennium Development Goals (MDGs), the World Health Organization/UNICEF Joint Monitoring Program (JMP) for Water Supply and Sanitation defines "improved" drinking water sources as follows:

Water sources that are not considered as "improved" are:

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