Water storage is extremely important because water is more essential than food in sustaining life during emergency periods. You can live for several days without food, but it is impossible to survive more than a few days without water. Plan to store at least 1 gallon of water per person per day. Take into consideration the size of the person, the amount of exertion being expended, the climate, and perspiration loss. Don't forget to include sufficient water for the family pets as well.
City tap water may be stored for an indefinite period of time without spoilage if simple precautions are taken. Store water in clean "food-grade" or PETE plastic containers. Do not use milk containers or the water that is sold in "milk" type jugs, the plastic is designed to deteriorate and will leak water all over. Stored water should be checked every few months to determine whether containers have leaked or if any undesirable characteristics have developed in appearance, taste or odor. If so, the water should be replaced. You should rotate/replace your water supply once a year. The water will still be good beyond that time, but will not be a desirable taste. Do not add bleach to water that is intended for long-term storage. Add it, if necessary, only at the time of use, then if possible, filter the water after it has been purified with bleach.
When filling the barrels, use a potable drinking water hose. They are lead free, and available at your local hardware store. Choose wisely where you will keep your barrels since a full 55 gallon drum will weigh 440 pounds. It is best to store water away from direct light and too much heat. If that is not feasible then make sure to check your water more often.
Here is a chart to follow to treat water with bleach if needed:
Tincture of Iodine 2% may also be used to treat water:
Clean water Cloudy water
3 drops per quart 6 drops per quart
12 drops per gallon 24 drops per gallon
Remember that cholera, typhoid fever, dysentery, diarrhea and infectious hepatitis are diseases often associated with unsafe water. Do not take the chance! Under serious disaster conditions, no water- except that which you have properly stored yourself- can be presumed safe, and all drinking and cooking water should be purified, filtered, and distilled.