Water supply

1Why WASH saves lives

In camps and affected areas, diseases related to water, sanitation and hygiene (diarrhoea, cholera, hepatitis E, typhoid) are among the leading causes of illness and death, especially among young children and malnourished people. WASH acts on faecal-oral transmission: through contaminated hands, water, food, flies and soil.

This is often summarised by the “F-diagram”: barriers (latrines, handwashing, treated water, food protection) break the transmission routes.

2Quantity and access: the Sphere benchmarks

• At least 15 litres per person per day for drinking, cooking and personal hygiene (an indicative benchmark to be adapted to the context, and higher in health facilities).
• A water point less than 500 metres from households.
• A queuing time at the water point of less than 30 minutes.
• As a benchmark, around 250 people per tap (depending on flow rate), 500 per hand pump, 400 per open hand-dug well.
• Clean containers for collection and storage at home (for example two 10- to 20-litre jerrycans per household).

These benchmarks are indicators, not quotas: they are discussed with communities, in particular women and girls, who often collect the water.

3Water supply options

• Water trucking: fast but expensive, to be replaced by sustainable solutions as soon as possible.
• Rehabilitation of existing boreholes, wells and networks: often the most cost-effective option.
• Surface water treatment (river, lake) with treatment units, or new boreholes after surveys.
• Management by trained water point committees (maintenance, cleanliness, minor repairs, possible user contribution).

4Treating water and monitoring its quality

• Chlorination: the most common method in emergencies. Benchmark: a free residual chlorine concentration of 0.2 to 0.5 mg/l at the point of delivery (higher, around 0.5 to 1 mg/l, during a cholera outbreak), after a contact time of at least 30 minutes, with low-turbidity water (ideally below 5 NTU).
• Measurement of residual chlorine with a comparator or photometer (DPD) several times a day at water points and in a sample of households.
• Bacteriological testing: 0 faecal coliforms (E. coli) per 100 ml at the point of delivery.
• Household water treatment (tablets, filters, boiling) when water cannot be treated at source, with demonstrations and follow-up.