An adequate supply of clean drinking water is an absolute priority during any emergency. A normally active person needs at least one gallon of drinking water daily. That would include about two quarts for drinking and the remainder for food preparation and personal hygiene. However, needs vary depending on the weather and an individual’s age and health status. When clean water is not available, it is necessary to purify all water before using it for drinking, making food, and personal hygiene.
Boiling or chlorinating contaminated water will destroy microorganisms, but will not remove chemicals. Distillation will remove microorganisms that resist these two methods as well as remove contaminants such as heavy metals, salts and most other chemicals. Before treating, let any particles settle to the bottom, or strain them through layers of paper towels, clean cloths or coffee filters.
Boiling Versus Chlorinating
Boiling is the safest and most reliable method to make water safe to drink. Bring water to a vigorous boil (3-4 minutes), and then allow it to cool. Follow your local health department recommendations if different.
Chemical disinfection can be used when boiling is not an option. Unscented liquid household bleach (do not use color safe, scented or with added cleansers) can be used to kill microorganisms. The bleach must be regular strength 5.25 percent sodium hypochlorite, which is clearly noted on the container. Depending on whether the water is clear or cloudy will determine how much bleach to use for disinfection.
If the water is clear, add 8 drops of bleach per gallon of water. If the water is cloudy, first skim off the clean water above the sediment, place in another clean container and then add 16 drops of bleach per gallon of water. Stir. Let stand for 30 minutes. Smell the water. If you don’t notice a slight bleach odor, add another dose of bleach and let stand another 15 minutes. Click here for a comprehensive guide on preparing and storing an emergency safe drinking water supply from the UF/IFAS Extension Service.