Here are some simple and inexpensive ways to purify your water:
Sunlight Sunlight kills many harmful germs. To purify water using sunlight, fill clean, clear glass or plastic containers with water, and leave them outside from morning to late afternoon. Be sure to place the containers in an open space where they will be in the sun all day. (If drinking water is needed right away, putting the containers in the sun for 2 hours in the middle of the day should be enough for purification.)
To avoid getting germs in the water, choose a spot away from children, dust, and animals. If you want the water to cool before using, bring the containers inside overnight. Water can be stored for a day or two in the same container. Sunlight purification works best in warm climates.
Lemon juice Lemon juice sometimes kills cholera (and some other germs). Add 2 tablespoons lemon juice to a liter (1 quart) of water and let it sit for 30 minutes.
Boiling Boiling water for 1 minute makes it safe from germs. Let it boil for 1 full minute before taking the pot off to cool. Because boiling water uses so much fuel, use this method only if there is no other way to purify your water.