If the water does not have a detectable chlorine smell at the end of this time, repeat the dose. If the water doesn't have a slight bleach odor at the end of another 15 minutes, try to find another source of water. To lessen the flat taste of boiled water, pour the water back and forth several times between two clean containers to add oxygen to the water. Having an ample supply of water is a top priority in an emergency. Everyone's needs will differ, depending upon age, physical condition, activity, diet and climate.
Hot environments can double the amount needed as the body uses water for cooling.
The amount of water you need will also depend on the total amount of juices, soups, other drinks, and high moisture foods that are available. Children, nursing women, and ill people will need more. You can minimize the amount of water your body needs by reducing your activity level. Additional water will be needed for food preparation and hygiene. In general, store at least one gallon of water per person, per day of expected need.