Basic drinking water service

The Joint Monitoring Programme, the WHO and UNICEF body that keeps the world's official water and sanitation statistics, sorts every household onto a ladder of five rungs. Basic is the middle rung, and the programme defines it as drinking water from an improved source, provided collection time is not more than 30 minutes for a round trip including queuing.

An improved source is one that, by its design and construction, has the potential to deliver safe water. The programme counts piped water, boreholes and tubewells, protected dug wells, protected springs, rainwater, and packaged or delivered water. An unprotected dug well or spring is unimproved, and water taken straight from a river, dam, lake, pond, stream or canal counts as surface water, the bottom rung.

Two things the label does not mean. It is not a claim that the water is safe to drink: freedom from faecal and priority chemical contamination belongs to the rung above, safely managed, which also requires the supply to be on the premises and available when needed. And the 30 minute limit is the whole of the difference between basic and the rung below it, limited, where the source is improved but the walk and the queue together take longer than that.