A safe supply of water is a priority in any survival situation.

You can live for several weeks without food, but without water you will only last about three or four days. A typical person will lose 2-3 liters of water per day under ordinary circumstances, but more in very hot or dry weather. Without water you will soon begin to experience dehydration resulting in lethargy, headaches, dizziness, confusion, and eventually death. Even mild dehydration impairs concentration, which is dangerous in a survival situation where clear thinking is a must. Dark yellow or brown urine indicates dehydration. Because of these risks, a safe supply of drinking water must be located as soon as a shelter has been found. (or even before, depending on conditions).

Once you have secured a source of H2O, whether it is a river or stream, rain collection, or by making a condensation trap or other means, it must be purified before you drink it. It will do you no good to drink 3 ounces of contaminated water, and then lose 10 times that over the next 12 hours becuase you have diarrhea all of a sudden. Contaminated water contains viruses and pathogens that can make your already bad day get a lot worse. It is possible to get Typhoid, Cholera, and Salmonella from drinking contaminated water. A small brook or stream may look very clean, but if there is a carcass of a dead animal upstream, the water may actually be contaminated.

The most common way to purify water in a survival situation is to heat it to the boiling point. This means finding some sort of container to hold water so it can be placed over a fire. If you are at a higher elevation, boil the water for several minutes, the boiling point for water is higher at elevations. Water can also be purified with solar distillation, portable pump filters, or chemical packs. Solar distillation is acheived by placing water in a transparent plastic bottle, oxygenating by shaking, and then placing in direct sunlight for 6 hours. The higher water temperature and solar radiation combine to kill the microbes in the water.