Amount to Store
In a disaster, water supplies may be cut off or contaminated. Store
enough water for everyone in your family to last for at least 3 days. Store 1 gallon of water, per person, per day. This amount will be adequate for general drinking purposes. Having 3 gallons per person, per day, will give you enough for cooking uses as well as for limited personal hygiene purposes. Do not forget to plan for your pets.
Store water in food grade plastic containers, such as clean 2-liter soft drink bottles. Heavy duty, reusable plastic water containers are also available at sporting goods stores.
Replace water at least once every 6 months.
Commercially Bottled "Spring" or "Drinking" Water
Keep water in its original container, and don’t re-store a bottle once it’s been opened.
Label bottles with their replacement date, and store in a cool, dark place.
Replace water at least once each year.
Treating Water After The Disaster
If you run out of stored drinking water, strain and treat water from your water heater or the toilet reservoir tank (except if you use toilet tank cleaners.) You cannot drink swimming pool or spa water, but you can use it for flushing toilets or washing.
Begin by straining any large particles of dirt by pouring the water through a couple of layers of paper towels or clean cloth.
Next, purify the water one of two ways:
Boil - Bring to a rolling boil and maintain for 3 to 5 minutes. To improve the taste, pour it back and forth between two clean containers to add oxygen back.
Disinfect - If the water is clear, add 8 drops of bleach per gallon. If it is cloudy, add 16. Shake or stir and then let stand for 30 minutes. A slight chlorine taste and smell is normal.