Your body loses water through normal body processes (sweating, urinating, defecating and even breathing). During
average daily exertion when the atmospheric temperature is 20 degrees Celsius (C) (68 degrees
Fahrenheit), the average adult loses and therefore requires 2 to 3 liters of water daily. Other factors, such
as heat exposure, cold exposure, intense activity, high altitude, burns, or illness, can cause your body to
lose more water. You must replace this water.
Our body consists of 60% water, 75% of our brain and lean muscles is water, and 83% of water in our blood.
Dehydration results from inadequate replacement of lost body fluids. It decreases your efficiency and, if
injured, increases your susceptibility to severe shock. Consider the following results of body fluid loss:
- A 2% dehydration, results in a feeling of thirst.
- A 5% dehydration, results in a feeling of being hot and tired, and strength and endurance decrease.
- A 10% dehydration, results in a feeling of delirium and blurred vision.
- A 20% dehydration, results in death.
The most common signs and symptoms of dehydration are:
- Dark urine with a very strong odor.
- Low urine output.
- Dark, sunken eyes.
- Emotional instability.
- Loss of skin elasticity.
- Delayed capillary refill in fingernail beds.
- Trench line down center of tongue.
- Thirst. Last on the list because you are already 2 percent dehydrated by the time you crave fluids.
In any situation where food intake is low, drink 6 to 8 liters of water per day. In an extreme climate,
especially an arid one, the average person can lose 2.5 to 3.5 liters of water per hour. In this type of
climate, you should drink 14 to 30 liters of water per day.
With the loss of water there is also a loss of electrolytes (body salts). The average diet can usually keep
up with these losses but in an extreme situation or illness, additional sources need to be provided. A
mixture of 0.25 teaspoon of salt to 1 liter of water will provide a concentration that the body tissues can
Of all the physical problems encountered in a survival situation, the loss of water is the most preventable.
The following are basic guidelines for the prevention of dehydration:
- Always drink water when eating. Water is used and consumed as a part of the digestion process
and can lead to dehydration.
- Acclimatize. The body performs more efficiently in extreme conditions when acclimatized.
- Conserve sweat not water. Limit sweat-producing activities but drink water.
- Ration water. Until you find a suitable source, ration your water sensibly. A daily intake of 500
cubic centimeter (0.5 liter) of a sugar-water mixture (2 teaspoons per liter) will suffice to prevent
severe dehydration for at least a week, provided you keep water losses to a minimum by limiting
activity and heat gain or loss.
You can estimate fluid loss by several means. A standard field dressing holds about 0.25 liter (one-fourth
canteen) of blood. A soaked T-shirt holds 0.5 to 0.75 liter.
You can also use the pulse and breathing rate to estimate fluid loss. Use the following as a guide:
- With a 0.75 liter loss the wrist pulse rate will be under 100 beats per minute and the breathing
rate 12 to 20 breaths per minute.
- With a 0.75 to 1.5 liter loss the pulse rate will be 100 to 120 beats per minute and 20 to 30
breaths per minute.
- With a 1.5 to 2 liter loss the pulse rate will be 120 to 140 beats per minute and 30 to 40 breaths
per minute. Vital signs above these rates require more advanced care.
Don't eat (especially dry food) if you cannot find water, because to digest food your body will need water.
If you're very thirsty and find water, drink it slowly, don't overload your system, try to drink every 10 minutes until you don't feel thirsty anymore.
Ways to Find Water
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.
More than three-fourths of your body is composed of fluids. Your body loses fluid as a result 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.
Almost any environment has water present to some degree, here are some:
Snow and ice can be melted. Warning: Do not eat snow or ice without melting! Eating snow and ice can reduce body temperature and will lead to more dehydration. Sea ice that is gray in color or opaque is salty. Do not use it without desalting it. Sea ice that is crystaline with a bluish cast has little salt in it.
At Sea: For sea water you need to use desalter kit, do not drink seawater without desalting.
Rain Water: Rain water is not the main source in survival situation but in case it rains and you're short of water it would be of a big help, try to find a wide container, because the width in this case is more important than the depth especially if it's going to rain only for a short time, you may want to occupy the widest surface possible to take advantage of every drop of rain the wider the better (a kids inflatable swimming pool would be nice). Also you can spread a big clean sheet of plastic and make a hole in the middle, place it about 2 feet above the ground, place a bucket underneath the plastic sheet, exactly underneath the hole, so that the rain collected from the big plastic would pour rain water through the hole into the bucket, you may need to empty the bucket to a bigger container and place it again under the hole. (try to make the center of the plastic form a V so that the rain water will accumulate only in the center by placing a clean stone in the center).
Water at the Beach: Dig a hole deep enough to allow water to seep in, obtain rocks, build fire and heat rocks, drop hot rocks in water, hold cloth over hole to absorb steam, wring water from cloth. The rocks will make the water evaporate, the cloth will capture the evaporated water and convert it into water.
Alternate method if a container or bark pot is available, fill container or pot with seawater, build fire and boil water to produce steam, hold cloth over container to absorb steam; wring water from cloth.
Water in the Desert: In deserts you can find water in:
- Valleys and low areas
- Foot of concave banks of dry river beads
- Foot of cliffs or rock outcrops.
- First depression behind first sand dune of dry desert lakes.
- Wherever you find damp surface sand
- Wherever you find green vegetation
After you spot one of the options above dig holes deep enough to allow water to seep in.
In a sand dune belt, any available water will be found beneath the original valley floor at the edge of dunes.
can contain a good source of water, once a barrel cactus is found cut off the top and mash or squeeze the pulp. Caution: do not eat pulp, place pulp in mouth, suck out juice and discard pulp. Without a machete cutting into a cactus is difficult and takes time since you must get past the long strong spines and cut through the tough rind.
Stills (Solar Stills): You can use stills in various areas of the world. They draw moisture from the ground and from plant
material. You need certain materials to build a still, and you need time to let it collect the water. It takes
about 24 hours to get 0.5 to 1 liter of water.
To make a belowground still, you need a digging tool, a container, a clear plastic sheet, a drinking tube,
and a rock (See image below).
Select a site where you believe the soil will contain moisture (such as a dry stream bed or a low spot
where rainwater has collected). The soil at this site should be easy to dig, and sunlight must hit the site
most of the day.
To construct the still:
- Dig a bowl-shaped hole about 1 meter across and 60 centimeters deep.
- Dig a sump in the center of the hole. The sump's depth and perimeter will depend on the size of
the container that you have to place in it. The bottom of the sump should allow the container to
- Anchor the tubing to the container's bottom by forming a loose overhand knot in the tubing.
- Place the container upright in the sump.
- Extend the unanchored end of the tubing up, over, and beyond the lip of the hole.
- Place the plastic sheet over the hole, covering its edges with soil to hold it in place.
- Place a rock in the center of the plastic sheet.
- Lower the plastic sheet into the hole until it is about 40 centimeters below ground level. It now
forms an inverted cone with the rock at its apex. Make sure that the cone's apex is directly over
your container. Also make sure the plastic cone does not touch the sides of the hole because the
earth will absorb the condensed water.
- Put more soil on the edges of the plastic to hold it securely in place and to prevent the loss of
- Plug the tube when not in use so that the moisture will not evaporate.
You can drink water without disturbing the still by using the tube as a straw.
You may want to use plants in the hole as a moisture source. If so, dig out additional soil from the sides
of the hole to form a slope on which to place the plants. Then proceed as above.
If polluted water is your only moisture source, dig a small trough outside the hole about 25 centimeters
from the still's lip (Figure 6-8). Dig the trough about 25 centimeters deep and 8 centimeters wide. Pour
the polluted water in the trough. Be sure you do not spill any polluted water around the rim of the hole
where the plastic sheet touches the soil. The trough holds the polluted water and the soil filters it as the
still draws it. The water then condenses on the plastic and drains into the container. This process works
extremely well when your only water source is salt water. Note: This can only be done as a last resort in absence of other water sources.
Rainwater collected in clean containers or in plants is usually safe for drinking. However, purify water
from lakes, ponds, swamps, springs, or streams, especially the water near human settlements or in the
When possible, purify all water you got from vegetation or from the ground by using iodine or chlorine, or
Purify water by:
- Using water purification tablets.
- Placing 5 drops of 2 percent tincture of iodine in a canteen full of clear water. If the canteen is full
of cloudy or cold water, use 10 drops. (Let the canteen of water stand for 30 minutes before
- Boiling water for 1 minute at sea level, adding 1 minute for each additional 300 meters above sea
level, or boil for 10 minutes no matter where you are.
By drinking nonpotable water you may contract diseases or swallow organisms that can harm you.
Examples of such diseases or organisms are:
- Dysentery. Severe, prolonged diarrhea with bloody stools, fever, and weakness.
- Cholera and typhoid. You may be susceptible to these diseases regardless of inoculations.
- Flukes. Stagnant, polluted water--especially in tropical areas--often contains blood flukes. If you
swallow flukes, they will bore into the bloodstream, live as parasites, and cause disease.
- Leeches. If you swallow a leech, it can hook onto the throat passage or inside the nose. It will
suck blood, create a wound, and move to another area. Each bleeding wound may become
Water Filtration Devices
If the water you find is also muddy, stagnant, and foul smelling, you can clear the water:
- By placing it in a container and letting it stand for 12 hours.
- By pouring it through a filtering system.
Note: These procedures only clear the water and make it more palatable. You will have to
To make a filtering system, place several centimeters or layers of filtering material such as sand, crushed
rock, charcoal, or cloth in bamboo, a hollow log, or an article of clothing.
Remove the odor from water by adding charcoal from your fire. Let the water stand for 45 minutes before
What not to Drink:
- Alcoholic beverages: dehydrate the body and cloud judgment.
- Urine: contains harmful body wastes and is 2 percent salt.
- Blood: is salty and considered a food, therefore requires additional body fluids to digest, and may transmit disease.
- Seawater: is about 4 percent salt. It takes about 2 liters of body fluids to rid the body of waste from 1 liter of seawater, therefore by drinking seawater you deplete your body's water supply, which can cause death.
More information: We hope this page was helpful and provided you with some survival techniques on how to find water or purify it in the wilderness. Check out our main page for more survival scenarios here Survival Guide, knowledge is light, and knowledge can save your life. Make sure you do your best to know what to do in a survival situation and then hope for the best.
Related Articles to Finding Water in the Wilderness