Many people need even more than the average of one gallon per day. The individual amount needed depends on age, physical activity, physical condition and time of year.
Never ration drinking water unless ordered to do so by authorities.
Drink the amount you need today and try to find more for tomorrow. Under no circumstances should a person drink less than one quart (four cups) of water each day. You can minimize the amount of water your body needs by reducing activity and staying cool.
Drink water that you know is not contaminated first.
If necessary, suspicious water, such as cloudy water from regular faucets or water from streams or ponds, can be used after it has been treated. If water treatment is not possible, put off drinking suspicious water as long as possible, but do not become dehydrated.
Do not drink carbonated beverages instead of drinking water.
Carbonated beverages do not meet drinking-water requirements. Caffeinated drinks and alcohol dehydrate the body, which increases the need for drinking water.
Turn off the main water valves.
You will need to protect the water sources already in your home from contamination if you hear reports of broken water or sewage lines or if local officials advise you of a problem. To close the incoming water source, locate the incoming valve and turn it to the closed position. Be sure you and your family members know how to perform this important procedure.