If your household's water source isn't reliably clean — from a river, unprotected well, or after flooding — there are several inexpensive ways to treat it before drinking. Bringing water to a rolling boil for about one minute kills the bacteria, viruses, and parasites that cause most waterborne illness.
Where fuel for boiling is scarce, water purification tablets or a few drops of unscented household bleach (check the recommended ratio on the product or with a health worker, since concentrations vary) can also make water safer, though boiling remains the most reliable method.
Store treated water in a clean, covered container, and use a clean cup or pour rather than dipping hands or used cups into the storage container, which can reintroduce contamination.
Cloudy or visibly dirty water should be filtered through a clean cloth before treatment, since suspended particles can shield some germs from chemical treatment or reduce boiling's effectiveness.