Water is one of your most urgent needs in a survival situation. You can’t live long without it, especially in hot areas where you lose water rapidly through perspiration. Even in cold areas, you need a minimum of 2 liters of water each day to maintain efficiency. Water helps you maintain your body temperature, lubricates and cushions organs, is required to metabolize body fat, and aids in digestion of foods that you eat. If you do not take in enough water, your body will begin pulling it from other places, including your blood. When water is extracted from your blood, the blood thickens making it more difficult for the heart to pump blood through your body. You become tired, listless, and will be unable to function properly.
More than three-fourths of your body is composed of fluids. Your body loses fluid because of heat, cold, stress, and exertion. To function effectively, you must replace the fluid your body loses. So, one of your first goals is to obtain an adequate supply of water and to do that, you must find a water source or build a water still to collect water. Then the water must be purified and or filtered before it is safe to drink.