Hesperian Health Guides
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We all need water. Drinking plenty of clean water keeps us healthy. We also need clean water for washing and preparing food. But in many places, water has dangerous germs and worm eggs in it that cause diarrhea and other diseases, including cholera and worms. For how to treat these diseases, see Chapter 12: Common health problems.
People with HIV are easily made sick by water that has germs in it. Even if everyone else in the house drinks the water without problems, the person with HIV drinking that water may get diarrhea from germs his body is not strong enough to fight. Young children also get sick more easily from germs in water.
How to know when water is OK to drink
You cannot tell that water is safe to drink by how it looks. Water that looks clean may still contain harmful germs, worms, and other sources of health problems. Unless you know it is safe, water should be treated or boiled before it is used for drinking or preparing food.
In most cases, spring water and deep well water are safe, unless there is contamination upstream from field or factory pollution, waste dumps, deep pit toilets, or other sources of germs and toxic chemicals.
Local universities, government agencies, or NGOs may be able to help you test your water for safety. If you doubt the safety of your water, treat it before using it.
|Fight illness with a good water supply.|
How to remove germs from your water
To make water safe for drinking, mixing with food, or washing food or utensils, it must be disinfected. A good first step is to settle any dirt in it and then pour the clear part out through a cloth or other filter to a new clean container. Disinfection works better with water that is clear.
To disinfect water so it is safe to drink, use one of these methods:
- Chlorine bleach (5%). Mix 8 drops of bleach into 4 liters (1 gallon) of water in a container. Let the water and bleach mix for 30 minutes before using. If the water looks dirty, use 16 drops of bleach and shake the mixture several times during the 30 minutes.
- Boiling. Heat water until it boils for 1 minute. At elevations over 2000 meters, boil for 3 minutes because the boiling water is not as hot. If you do not have enough fuel for boiling, heat the water so it is too hot to touch — this kills most germs.
- Sunlight. Fill clean, clear plastic or glass bottles with water, and close them. Place the bottles where they will be in the sun, away from dust, children, and animals, and leave them for at least 6 full hours, or for 2 days if the weather is cloudy. Water can be stored for 1 or 2 days in the same bottle. Sunlight purification works best in very hot places.
- A filter like this, with sand and charcoal, is slow but makes water safe to drink in one step. See A Community Guide to Environmental Health from Hesperian for more ways to build filters, how to make stoves that use less fuel for boiling water, and other ideas for making water safe.
WARNING! These methods do not remove toxic chemicals. Water polluted with toxic chemicals is never safe for drinking, bathing, or washing. Do not store water in containers that have held pesticides or dangerous chemicals, even if they have been cleaned. See A Community Guide to Environmental Health, for more about toxic chemicals and water.
How to store clean water
Water can get germs in it when someone touches it with dirty hands or dips a dirty cup in it, when clean water is poured into a dirty cup or other vessel, and when dirt or dust gets into the water. To prevent water from becoming unsafe while stored or served:
- wash your hands before collecting and carrying water.
- clean the containers that you use to carry and store water, and all cups used for drinking.
- carry water in covered containers and keep water containers off the floor and away from animals.
- when you pour water out, do not touch the mouth of the container or the water with your hands. Or use a clean, long-handled dipper to take water out.