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The human body can survive about 30 days without food but less than a week without water under cool to moderate conditions.  As outside temperatures rise the survivability without water drastically plummets.  In order to survive you must have water.

The minimum amount of water you should have stored for a disaster is:


For a family of four this translates to:

1 gallon x 4 people x 5 days = 20 gallons MINIMUM

Do not forget to include pets in the equation as well.  So in the above example a family of four with a dog and a cat needs:

1 gallon x 6 people/animals x 5 days = 30 gallons MINIMUM

Three gallons a day minimum will require a great deal of water conservation on your part.  If possible a seven day supply would be much more preferable. Water supplies should be changed once a year at a minimum.

If your water supply is shut off any your stored emergency supplies have been exhausted, there are several alternative sources.

  1. Water heaters tanks may be shut off and drained

  2. Water from unsalted canned vegetables may be used

If you are unsure of the quality of the water, purify it before drinking.  You can heat water to a rolling boil for 10 minutes, use purification tablets, or use unscented 5.25% household liquid bleach to purify.  To purify using bleach add bleach to the water, shake or stir the container then let it stand for 30 minutes before drinking.  For amounts of bleach to add use the following table as a guide:

Water Quantity

Bleach Added

1 quart

4 drop from a medicine dropper

1 gallon

16 drops from a medicine dropper

5 gallons

1 teaspoon