Survival Wisdom & Know-How

Our bodies are composed of approximately 60 percent water, and it plays a vital role in our ability to get through a day. About 70 percent of our brains, 82 percent of our blood, and 90 percent of our lungs are composed of water. In our bloodstream, water helps to metabolize and transport vital elements, carbohydrates, and proteins that are necessary to fuel our bodies. Water also helps us dispose of our bodily waste.

Water Requirements

During a normal, nonstrenuous day, a healthy individual will need 2 to 3 quarts of water. When physically active or in extreme hot or cold environments, that same person would need at least 4 to 6 quarts of water a day. Being properly hydrated is one of the various necessities that wards off dehydration and environmental injuries. A person who’s mildly dehydrated will develop excessive thirst and become irritable, weak, and nauseated. As the dehydration worsens, individuals will show a decrease in their mental capacity and coordination. At this point it will become difficult to accomplish even the simplest of tasks. The ideal situation would dictate that you don’t ration your water. Instead you should ration sweat. If water is not available, don’t eat.

Dispelling Myths About Water

Never Drink Urine!

By the time you think about drinking your urine, you are very dehydrated, and your urine would be full of salts and other waste products. For a hydrated person, urine is 95 percent water and 5 percent waste products like urea, uric acid, and salts. As you become dehydrated, the concentration of water decreases and the concentration of salts increases substantially. When you drink these salts, the body will draw upon its water reserves to help eliminate them, and you will actually lose more water than you might gain from your urine.

Never Drink Salt Water!

The concentrations of salts in salt water are often higher than those found in urine. When you drink these salts, the body will draw upon its water reserves to help eliminate them, and you will actually lose more water than you might gain from salt water.

Never Drink Blood!

Blood is composed of plasma, red blood cells, white blood cells, and platelets. Plasma, which composes about 55 percent of the blood’s volume, is predominately water and salts, but it also carries a large number of important proteins (albumin, gamma globulin, and clotting factors) and small molecules (vitamins, minerals, nutrients, and waste products). Waste products produced during metabolism, such as urea and uric acid, are carried by the blood to the kidneys, where they are transferred from the blood into urine and eliminated from the body. The kidneys carefully maintain the salt concentration in plasma. When you drink blood, you are basically ingesting salts and proteins, and the body will draw upon its water reserves to help eliminate them. You will actually lose more water than you might gain from drinking blood.

—From Wilderness Survival

Finding Water in the Wild

Greg Davenport

Insects

If bees are present, water is usually within several miles of your location. Ants require water and will often place their nest close to a source. Swarms of mosquitoes and flies are a good indicator that water is close.

Birds

Birds frequently fly toward water at dawn and dusk in a direct, low flight path. This is especially true of birds that feed on grain, such as pigeons and finches. Flesh-eating birds can also be seen exhibiting this flight pattern, but their need for water isn’t as great, and they don’t require as many trips to the water source. Birds observed circling high in the air during the day are often doing it over water, as well.

Frogs and Salamanders

Most frogs and salamanders require water and if found are usually a good indicator that water is near.

Mammals

Like birds, mammals will frequently visit watering holes at dawn and dusk. This is especially true of mammals that eat a grain or grassy-type diet. Watching their travel patterns or evaluating mammal trails may help you find a water source. Trails that merge into one are usually a good pointer and following the merged trail often leads to water.

Land Features that Indicate Water

Drainages and valleys are a good water indicator, as are winding trails of deciduous trees. Green plush vegetation found at the base of a cliff or mountain may indicate a natural spring or underground source of water.

Dowsing

Dowsing, or witching, is a highly debated skill that some say helps them find water. Those who profess to have this skill use a forked stick (shaped like a Y) about 18 to 20 inches long and ⅛ to ¼ inch in diameter. The most common branch used comes from a willow tree. The two ends of the Y are held in the hands, which are positioned palms up, while the dowser walks forward. The free end of the stick is supposed to react when it passes over water. This reaction may be toward or away from the body.

—From Wilderness Living

Water Sources and Procurement

Greg Davenport
Illustrations by Steven Davenport and Ken Davenport

Since your body needs a constant supply of water, you will eventually need to procure water from Mother Nature. Various sources include surface water, ground water, precipitation, condensation, plant sources, and man-made options that transform unusable sources.

Surface Water

Surface water may be obtained from rivers, ponds, lakes, or streams. It is usually easy to find and access, but because it is prone to contamination from protozoan, viruses, and bacteria, it should always be treated. If the water is difficult to access or has an unappealing flavor, consider using a seepage basin to filter the water. The filtering process is similar to what happens as ground water moves toward an aquifer. To create a seepage basin well, dig a 3-foot-wide hole about 10 feet from your water source. Dig it down until water begins to seep in, and then dig about another foot. Line the sides of your hole with wood or rocks so that no more mud will fall in, and let it sit overnight so the dirt and sand will settle.

Two trails that merge together often point toward water.

Ground Water

Ground water is found under the earth’s surface. This water is naturally filtered as it moves through the ground and into underground reservoirs called aquifers. Although treating this water may not be necessary, you should always err on the side of caution. Locating ground water is probably the most difficult part of accessing it. Look for things that seem out of place, such as a small area of green plush vegetation at the base of a hill or a bend in a dry riverbed that is surrounded by vegetation. A marshy area with a fair amount of cattail or hemlock growth may provide a clue that ground-water is available. Using these same clues, I have found natural springs in desert areas and running water less than 6 feet below the earth’s surface. To easily access the water, dig a small well at the source (see direction for seepage basin above), line the well with wood or rocks, and let it sit overnight before using the water. When close to shore, you can procure fresh water by digging a similar well one dune inland beyond the beach.

Seepage basin well.

Dry riverbed water source.

Precipitation

The four forms of precipitation are rain, snow, sea ice, and dew.

Rain

When it rains, you should sit out containers or dig a small hole and line it with plastic or any other nonporous material to catch the rainwater. After the rain has stopped, you may find water in crevasses, fissures, or low-lying areas.

Snow

Snow provides an excellent source of water, but it should not be eaten. The energy lost eating snow outweighs the benefit. Instead, melt it by suspending it over a fire or adding it to a partially full canteen and then shaking the container or placing it between the layers of your clothing and allowing your body’s radiant heat to melt the snow. If you are with a large group, a snow-to-water generator can be created from a tripod and porous material. Create a large pouch by attaching the porous material to the tripod. Fill the pouch with snow, and place the tripod just close enough to the fire to start melting the snow. Use a container to collect the melted snow. Although the water will taste a little like smoke, this method provides an ongoing large and quick supply of water. If the sun is out, you could melt the snow by digging a cone-shaped hole, lining it with a tarp or similar nonporous material, and placing snow on the material at the top of the cone. As the snow melts, water will collect at the bottom of the cone.

Snow water generators produce large volumes of water from snow.

Sea Ice

If using sea ice, you will want to make sure the ice is virtually free of any salts in the sea water. Sea ice that has rounded corners, shatters easily, and is bluish or black is usually safe to use. When in doubt, however, do a taste test. If it tastes salty, don’t use it. As with snow, ice should be melted prior to consumption. Melt sea ice next to a fire or add it to a partially full container of water and either shake the container or place it between the layers of your clothing and allow your body’s radiant heat to melt the snow.

Dew

Although dew does not provide a large volume of water, it should not be overlooked as a source of water. Dew accumulates on grass, leaves, rocks, and equipment at dawn and dusk and should be collected at those times before it freezes or evaporates. Any porous material will absorb the dew, and the moisture can be consumed by wringing it out of the cloth and into your mouth.

Condensation

Solar stills are a great water procurement option in hot climates. The vegetation bag and transpiration bag are great land options.

Vegetation Bag

To construct a vegetation bag, you will need a clear plastic bag and an ample supply of healthy, nonpoisonous vegetation. A 4- to 6-foot section of surgical tubing is also helpful. To use, open the plastic bag and fill it with air to make it easier to place vegetation inside. Next fill the bag one-half to three-quarters full of lush green vegetation. Be careful not to puncture the bag. Place a small rock or similar item into the bag, and if you have surgical tubing, slide one end inside and toward the bottom of the bag. Tie the other end in an overhand knot. Close the bag, and tie it off as close to the opening as possible. Place the bag on a sunny slope so that the opening is on the downhill side slightly higher than the bag’s lowest point. Position the rock and surgical tubing at the lowest point in the bag. For best results, change the vegetation every two to three days. If using surgical tubing, simply untie the knot and drink the water that has condensed in the bag. If no tubing is used, loosen the tie and drain off the available liquid. Be sure to drain off all liquid prior to sunset each day, or it will be reabsorbed into the vegetation.

Vegetation bag.

Transpiration Bag

Because the same vegetation can be reused after allowing enough time for it to rejuvenate, a transpiration bag is better than a vegetation bag. To construct a transpiration bag, you will need a clear plastic bag and an accessible, nonpoisonous brush or tree. A 4- to 6-foot section of surgical tubing is also helpful. Open the plastic bag and fill it with air to make it easier to place the bag over the brush or tree. Next place the bag over the lush leafy vegetation of a tree or brush, being careful not to puncture the bag. Be sure the bag is on the side of the tree or brush with the greatest exposure to the sun. Place a small rock or similar item into the bag’s lowest point, and if you have surgical tubing, place one end at the bottom of the bag next to the rock. Tie the other end in an overhand knot. Close the bag, and tie it off as close to the opening as possible. Change the bag’s location every two to three days to ensure optimal outcome and to allow the previous site to rejuvenate so it might be used again later. If using surgical tubing, simply untie the knot and drink the water that has condensed in the bag. If no tubing is used, loosen the tie, and drain off the available liquid. Be sure to drain off all liquid prior to sunset each day, or it will be reabsorbed into the tree or brush.

Transpiration bag.

Vegetation

Depending on your location, you may find an abundant source of water from vegetation. Plants and trees with hollow portions or leaves that overlap, such as air plants and bamboo, often collect rainwater in these natural receptacles. Other options include cacti, water vines, banana trees, and coconuts.

Cacti

Cacti are prominent in the deserts of the Southwest and can provide a limited supply of liquid. To procure it, cut off the top of a cactus (this will be difficult without a large knife because the cactus has a tough outer rind), remove the inner pulp, and place it inside a porous material, such as a cotton T-shirt. The pulp’s moisture can now be easily wrung out directly into your mouth or an awaiting container. Since the amount of fluid obtained will be minimal, don’t eat the pulp. It will require more energy and body fluids to digest the pulp than can be gained from it.

Banana Trees

Banana trees are common in the tropical rain forests and can be made into an almost unending water source by cutting them in half with a knife or machete, starting about 3 inches from the ground. Next, carve a bowl into the top surface of the trunk. Water will almost immediately fill the bowl, but do not drink it; the initial water will be bitter and upsetting to your stomach. Scoop the water completely out of the bowl three times before consuming.

The initial water from a banana tree will be very bitter and should be avoided.

Water Vines

Water vines average from 1 to 6 inches in diameter, are relatively long, and usually grow along the ground and up the sides of trees. Not all water vines provide drinkable water. Avoid water vines that have a white sap when nicked, provide cloudy milklike liquid when cut, or produce liquids that taste sour or bitter. Nonpoisonous vines will provide a clear fluid that often has a woody or sweet taste. To collect the water, cut the top of the vine first and then cut the bottom, letting the liquid drain into an awaiting container. If you plan to drink it directly from the vine, avoid direct contact between your lips and the outer vine as an irritation sometimes results.

Coconuts

Green unripe coconuts about the size of grape-fruits provide an excellent source of water. Once coconuts mature, however, they contain an oil, which, if consumed in large quantities, can cause an upset stomach and diarrhea. If you do not have a knife, accessing the liquid in coconuts presents the greatest challenge.

Water Filters

Filtering water does not purify it. Filtering is done to reduce sediment and make the water taste better. There are several methods of filtering water.

Seepage basin

This system is used for stagnant or swamp water. For best results, dig a hole approximately 3 feet from the swamp to a depth that allows water to begin seeping in. Line the sides with rocks or wood to prevent dirt or sand from falling back into the hole. Allow the water to sit overnight so that all the sediment can settle to the bottom.

Three-Tiered Tripod Filter

This system should be used for filtering sediment from the water. To construct it, you’ll need three 7- to 8-foot-long wrist-diameter poles, line, three 3-foot-square sections of porous cloth, grass, sand, and charcoal.

1. Build a tripod with the poles and line by laying the poles down, side by side, and lashing them together 6 inches to 1 foot from the top. For details on lashing see chapter 13.

WATER IMPURITIES

Greg Davenport

According to the Centers for Disease Control (CDC), water contaminated with microorganisms causes over a million illnesses and a thousand deaths in the United States each year. The primary disease-causing organisms, or pathogens, fall into three categories: protozoans (including cysts), bacteria, and viruses. Contaminants may also pose a problem.

Protozoans

Protozoans are one-celled organisms that vary in size from 2 to 100 microns, live in many insects and animals, and survive in cysts (protective shells) when outside of an organism. They include Giardia and Cryptosporidium. It takes only a few organisms to infect someone, and once inside a host, protozoans rapidly reproduce, causing severe diarrhea, abdominal cramps, bloating, fatigue, and weight loss.

Bacteria

Bacteria can be as tiny as 0.2 microns, much smaller than protozoans. They include typhoid, paratyphoid, dysentery, and cholera. Bacteria are often present in both wild and domestic animals. Once in the water, they can survive for weeks, even longer if frozen in ice.

Viruses

Viruses can be as small as 0.004 microns, which makes it easy for them to pass through a filter. Viruses found in water include hepatitis A and E, Norwalk virus, rotavirus, echovirus, and poliovirus. Unlike protozoans and bacteria, there is no treatment for a waterborne viral infection, and this makes them a significant health risk, especially for people with a compromised immune system.

Contaminants

Other impurities that can be found in water include disinfectants and their byproducts, inorganic and organic chemicals, and radionuclides.

Other Water You Should Avoid

Avoid collecting water from areas with oily films or slicks, significant algae overgrowth, or near dead animals. If this is your only water source, you may decide to dig a natural filtration system in the ground close by as a means of collecting this water, or perhaps pour it through a three-tiered filter and then treat it prior to drinking it.

—From Surviving the Desert

2. With the lashed end up, spread the legs of the poles out to form a stable tripod.

3. Tie the three sections of cloth to the tripod in a tiered fashion with a 6-inch to 1-foot space between each section.

4. Place grass on the top cloth, sand on the middle cloth, and charcoal on the bottom cloth.

5. To use, simply pour the water into the top section of cloth and collect it as it filters through the bottom section.

Cloth Filter

Any porous material can be used to filter out sediment by simply pouring your liquid through it and into a container.

Water Purification

According to the Centers for Disease Control (CDC), water contaminated with microorganisms will cause over 1 million illnesses and 1,000 deaths in the United States each year. The primary pathogens (disease-causing organisms) fall into three categories: protozoan (including cysts), bacteria, and viruses. Other potential risks that can be found in water include disinfectants and their by-products, inorganic chemicals, organic chemicals, and radionuclides. There are three basic methods for treating your water: boiling, chemical treatments, and commercial filtration systems.

Boiling

To kill any disease-causing microorganisms that might be in your water, the Environmental Protection Agency’s (EPA) Office of Water advocates using a vigorous boil for one minute. My rational mind tells me that this must be based on science and should work. After seeing a friend lose about 40 pounds from a severe case of giardiasis, however, I tend to over-boil my water. As a general rule, I almost always boil it longer. I’ll let you decide what is right for you. Boiling is far superior to chemical treatments and should be done whenever possible.

Chemical Treatments

When unable to boil your water, you may elect to use chlorine or iodine. These chemicals are effective against bacteria, viruses, and Giardia, but according to the EPA, there is some question about their ability to protect you against Cryptosporidium. In fact, the EPA advises against using chemicals to purify surface water. Once again, I’ll let you decide. Chlorine is preferred over iodine since it seems to offer better protection against Giardia. Both chlorine and iodine tend to be less effective in cold water.

Three-tiered tripod.

CHLORINE

The amount of chlorine to use for purifying water will depend upon the amount of available chlorine in the solution. This can usually be found on the label.

WATER PURIFIER CARE

Greg Davenport

To increase the longevity of your system, use the following guidelines (in no way should they supersede the manufacturer’s recommendations):

• Cleaning. Clean, scrub, and disinfect the filter after each use, following the manufacturer’s guidelines. Note: Some filters should not be scrubbed, and some are self-cleaning.

• Use clean water. Whenever possible, procure clean water such as that found in a creek’s pools or similar areas. To avoid sand, mud, and debris, keep the suction hose away from the water’s bottom; this may require the use of a foam float.

• Muddy water. If muddy water is your only choice, fill a clean container with the muddy water and let it sit for several hours (overnight if time permits) or until the sediment has settled to the bottom of the container. Or you could first run the water through an improvised filter, as described above.

• Backwash the filter. Backwash the filter according to the manufacturer’s recommended schedule. This process helps remove any accumulated debris from the system.

—From Surviving the Desert

If the water is cloudy or colored, double the normal amount of chlorine required for the percentage used. Once the chlorine is added, wait three minutes, and then vigorously shake the water with the cap slightly loose (allowing some water to seep out through the seams). Then seal the cap on the container, and wait another twenty-five to thirty minutes before loosening the cap and shaking it again. At this point consider the water safe to consume, provided there is no Cryptosporidium in the water.

IODINE

There are two types of iodine that are commonly used to treat water: tincture and tablets. The tincture is nothing more than the common household iodine that you may have in your medical kit. This product is usually a 2 percent iodine solution, and you’ll need to add five drops to each quart of water. For cloudy water, double the amount. The treated water should be mixed and allowed to stand for thirty minutes before used. If using iodine tablets, you should place one tablet in each quart of water when it is warm and two tablets per quart when the water is cold or cloudy. Each bottle of iodine tablets should have instructions for how it should be mixed and how long you should wait before drinking the water. If no directions are available, wait three minutes, and then vigorously shake the water with the cap slightly loose (allowing some water to seep out through the seams). Then seal the cap on the container, and wait another twenty-five to thirty minutes before loosening the cap and shaking it again. At this point consider the water safe to consume, provided the water does not contain Cryptosporidium.

Commercial Purifying Systems

A filter is not a purifying system. In general, filters remove protozoan; microfilters remove protozoan and bacteria; and purifiers remove protozoan, bacteria, and viruses. Purifiers are simply a microfilter with an iodine and carbon element added. The iodine kills viruses, and the carbon element removes the iodine taste and reduces organic chemical contaminants like pesticides, herbicides, and chlorine, as well as heavy metals. Unlike filters, purifiers must be registered with the EPA to demonstrate effectiveness against waterborne pathogens, protozoan, bacteria, and viruses. A purifier costs more than a filter. You’ll need to decide what level of risk you are willing to take, as waterborne viruses are becoming more and more prominent. One downside is that a purifier tends to clog more quickly than most filters. To increase the longevity of your system, you should carefully read and follow the manufacturer’s guidelines on how to use and clean the system you have. Purifiers come in a pump style or a ready-to-drink bottle design.

PUMP PURIFIERS

There are many pump filters on the market, and new ones arrive each year. As a purifying system, they protect against protozoan, bacteria, and viruses. I advise choosing a system that is lightweight, easy to use, has a high output, and is self-cleaning.

BOTTLE PURIFIERS

Probably the best-known bottle filter is the 34-ounce Exstream Mackenzie, an ideal system for the wilderness traveler. As a purifying system, it protects against protozoan, bacteria, and viruses. The benefit of a bottle purifier is its ease of use—simply fill the bottle with water and start drinking (according to the manufacturer’s directions). It requires no assembly or extra space in your pack. On the downside, it only filters about 26 gallons (100 liters) before you’ll need to replace the cartridge, and unless you carry several, you will need to be in an area with multiple water sources throughout your travel.

—From Wilderness Survival

Is Wild Water Safe?

Linda Frederick Yaffe

The water fushing over rocks, shooting bubbly plumes into the air, forming blue pools, looks so clean, so inviting. Can you safely dip your cup into the clear blue pool and enjoy a refreshing drink?

Today, pollution from larger numbers of careless outdoorspeople and infected wildlife compel you to treat all of the water you drink, use to clean your teeth, and use to prepare your food. Never drink untreated water, no matter how “clean” it appears. Most of the surface water in the United States is contaminated with Giardia lamblia and Cryptosporidium. These disease-causing microorganisms are invisible to the naked eye. They can make you seriously ill, causing months of stomach cramps, diarrhea, nausea, dehydration, and fatigue. Cases of Giardia, the most common waterborne pathogen, have more than doubled in the United States during the past decade.

Giardia and Cryptosporidium are spread through fecal-oral transmission. They are passed from person to person and from domestic and wild animals to humans. You can avoid spreading these pathogens by using good field practices and common sense. Camp at least 200 feet from any water source. Properly bury your feces, pack out toilet paper, and always wash your hands thoroughly with soap and water after defecating or changing a diaper and before handling food. When scouting for a water source, use the best-looking one available. Avoid water that contains floating material or water with a dark color or an odor. Filter murky water through a clean cloth before treating it. …

Carry plenty of treated water from home. Always carry five to ten gallons of treated water from home in your vehicle. Pack in as much as you can comfortably carry and have plenty available in your vehicle when you pack out of the wilderness.

—From Backpack Gourmet

Treating Water: Comparing Methods

Linda Frederick Yaffe

Fortunately, you can choose from several effective drinking water treatment methods: boiling, filtering, purifying, ultraviolet purification, or chemical treatment (tablets). Choose the method or combination of methods that suit the locale of your trip, your style of camping for the trip, and your personal preference.

Boiling

This is the most effective, fail-safe field treatment method. Vigorously boil untreated water for one to two minutes to kill the microorganisms that can make you ill.

Advantages: This is a very effective and inexpensive method. Anyone with a cooking pot, a stove and fuel, or the resources to build an open fire, can treat as much water as they need, anywhere in the world.

Disadvantages: Boiling all of your drinking water is inconvenient unless you are staying in a base camp. It is time and fuel consuming to boil quantities of water, and then let it cool enough to drink. While you are base-camped, it is feasible to spend the evenings boiling and filling containers with purified water, but it is a big chore. Boiled water, having lost oxygen in the process, tastes unpleasantly flat. Aeration (pouring the boiled water back and forth from one clean container to another) can improve the flat taste. Try letting the boiled water stand for several hours or overnight, or add a small pinch of salt to each quart of boiled water to improve the flavor. Since the taste of good mountain water is one of the attractions of a wilderness adventure, boiled water makes the trip less special.

Water Filters

Choose a modern microporous water filter to pump water from a groundwater source into your water container. Look for a filter that has an absolute pore size of one micron or less for protection from Cryptosporidium as well as Giardia.

Advantages: Cool, good-tasting treated water is available immediately. In areas of frequent surface water availability, the filter weighs far less than extra containers filled with clean water.

Disadvantages: Filters weigh from eleven to twenty-three ounces. They are costly. You need to clean filters regularly and periodically replace the filtering cartridges. Filters do not protect against waterborne viruses such as polio and hepatitis. Waterborne viruses are rare in North America but prevalent in some other parts of the world.

Water Purifies

These are water filters with an added purifying device that forces the water through chlorine beads, killing most viruses as well as the Giardia and Cryptosporidium parasites.

Advantages: Worry-free water treatment.

Disadvantages: Purifiers are slightly heavier and more costly than regular water filters.

Water filter and bottle.

Ultraviolet Purification

A portable battery-powered wand uses ultraviolet light to neutralize bacteria, viruses, and protozoa.

Advantages: The wand is fast and easy to use: Just swish the device around in a container of water. No pumping is required, and there are no chemical flavors.

Disadvantages: This technology is new to the backcountry. It is costly.

Water Purification Tablets

Tiny, lightweight tablets kill viruses in ground-water, but they do not effectively eliminate Giardia or Cryptosporidium.

Advantages: Convenient and lightweight, the tablets effectively kill waterborne viruses. They can be used as emergency substitutes only when you are unable to boil or filter your water. Potable Aqua treatment tablets, used with P.A. Plus, which is added twenty minutes after the first tablets, erase the unpleasant iodine taste of the initial tablets. The flavor can be further improved by letting the water stand for several hours or by adding powdered drink mix.

Disadvantages: Not as effective as boiling, filtering, purifying, or ultraviolet purification, tablets are an excellent supplement to filtering your water in parts of the world where viruses are a threat.

—From Backpack Gourmet

Drinking Water at Sea

Greg Davenport

Packed Water

Packed water, which comes inside a pouch or a box, holds between ⅛ to 1 quart of water. USCG-approved packed water has a five-year shelf life. While emergency water is a great item to carry on your trip, you should also carry something that allows you to procure additional water once your emergency supply is gone. Be sure to protect the pouches and boxes of packed water so they aren’t accidentally punctured. Storing them inside a hard plastic 1-quart water bottle (big-mouthed screw top) will not only protect them but will provide a container that will come in handy for storing other water that you procure. An option to the packed water would be to bring along tap water inside the hard plastic 1-quart container. The shelf life for tap water is approximately six months.

Desalting Tablets

One desalting tablet will desalt 1 pint of water. Salt water treated this way tastes like water obtained from a water hose that has set out in the sun all day. Desalting tablets come alone or in a kit. Kits have a plastic bag that holds about 1 pint of water and has a filter that will keep the sludge by-product from being drunk. To use, place seawater in the bag with the tablet, and wait one hour—agitating the water periodically—before drinking the water through the valve attached to the bag. If you don’t have a kit, follow the same process using an available container, and be sure not to drink the sludge left at the bottom.

Solar Stills

A solar still uses seawater and the sun to create drinkable water through a condensation process. Most stills are inflatable balls that allow you to pour seawater into a cup on top of the bottom. The balloon has a donut-shaped ballast ring that keeps it afloat and upright. It takes about a ½ gallon of seawater to fill the ballast. Note that the ballast ring has a fabric-covered center that must be wet before the balloon can be inflated. Additional seawater is required to fill the cup on top of the balloon, and this water provides a constant drip onto multiple cloth wicks located inside the balloon. As the outside air warms, condensation forms on the inner wall and runs down into a plastic container. The use of a solar still is limited to calm seas, and results will depend on temperatures. When seas are calm, stills should be put out as soon as possible even if clouds obscure the sun. For complete details on how to use these devices, read the manufacturers’ directions.

Solar still.

Reverse Osmosis Water Maker

Standard freshwater filters and purifiers will not desalt seawater and should not be used for this process. Instead, a reverse osmosis water maker that turns seawater into drinkable water should be part of your survival gear. These hand-powered devices range in weight from 2 to 7 pounds and can roughly produce 6 gallons of water a day, depending on the model you have. To use, simply place the hose of the device into seawater and pull the handle. To achieve the maximum amount of water output requires a pump rate of thirty to forty times a minute. Be sure to follow the manufacturer’s maintenance and use instructions, and have the system serviced accordingly.

Collecting Precipitation

Most life rafts have canopies designed to catch rainwater. This catchment system uses gutters to funnel rainwater into a storage container inside the raft. Since salt spray has probably dried on top of the canopy, the initial water collected will probably be too contaminated to drink. Lining the gutters, when it starts to rain, with a space blanket or similar material can alleviate this problem. Contamination can also be an issue in rough seas where the wind and waves constantly splash seawater onto the canopy and raft. You can also procure rainwater by tying a piece of plastic (a space blanket or similar item) to two paddles and holding it out the raft’s door in such a way as to funnel the rain into an awaiting container. Try to fill all available containers with rainwater, and drink this water before packaged water.

Water from Dew

Although dew does not provide a large amount of water, it should not be overlooked as a source of water. Dew accumulates on the raft and canopy (on land, it can be found on grass, leaves, rocks, and equipment) at dawn and dusk and should be collected at those times before it freezes or evaporates. Any porous material will absorb the dew, and the moisture can be consumed by wringing the water out of the cloth and into your mouth.

Ice

As with snow, ice should be melted prior to consumption. To melt ice, add it to a partially full container of water and either shake the container or place it between layers of your clothing and allow your body’s radiant heat to melt the snow. On land, you can melt ice with a fire. If using sea ice, you will want to make sure the ice is virtually free of any salts in the seawater. Sea ice that has rounded corners, shatters easily, and is bluish or black in color is usually safe to use. When in doubt, however, do a taste test. If it tastes salty, don’t use it.

—From Surviving Coastal and Open Water

Water Needs in High-Temperature Areas

U.S. Army

The subject of man and water in the desert has generated considerable interest and confusion since the early days of World War II when the U.S. Army was preparing to fight in North Africa. At one time the U.S. Army thought it could condition men to do with less water by progressively reducing their water supplies during training. They called it water discipline. It caused hundreds of heat casualties.

A key factor in desert survival is understanding the relationship between physical activity, air temperature, and water consumption. The body requires a certain amount of water for a certain level of activity at a certain temperature. For example, a person performing hard work in the sun at 43 degrees C requires 19 liters of water daily. Lack of the required amount of water causes a rapid decline in an individual’s ability to make decisions and to perform tasks efficiently.

Your body’s normal temperature is 36.9 degrees C (98.6 degrees F). Your body gets rid of excess heat (cools off) by sweating. The warmer your body becomes—whether caused by work, exercise, or air temperature—the more you sweat. The more you sweat, the more moisture you lose. Sweating is the principal cause of water loss. If a person stops sweating during periods of high air temperature and heavy work or exercise, he will quickly develop heat stroke. This is an emergency that requires immediate medical attention.

Understanding how the air temperature and your physical activity affect your water requirements allows you to take measures to get the most from your water supply. These measures are—

• Find shade! Get out of the sun!

• Place something between you and the hot ground.

• Limit your movements!

• Conserve your sweat. Wear your complete uniform to include T-shirt. Roll the sleeves down, cover your head, and protect your neck with a scarf or similar item. These steps will protect your body from hot-blowing winds and the direct rays of the sun. Your clothing will absorb your sweat, keeping it against your skin so that you gain its full cooling effect. By staying in the shade quietly, fully clothed, not talking, keeping your mouth closed, and breathing through your nose, your water requirement for survival drops dramatically.

• If water is scarce, do not eat. Food requires water for digestion; therefore, eating food will use water that you need for cooling.

Thirst is not a reliable guide for your need for water. A person who uses thirst as a guide will drink only two-thirds of his daily water requirement. To prevent this “voluntary” dehydration, use the following guide:

Daily water requirements for three levels of activity:

A: Hard work in sun (creeping and crawling with equipment on).

B: Moderate work in sun (cleaning weapons and equipment).

C: Rest in shade.

This graph shows water needs, in liters per day, for men at three activity levels in relation to the daily mean air temperature. For example, if one is doing 8 hours of hard work in the sun (curve A) when the average temperature for the day is 50 degrees C (horizontal scale), one’s water requirement for the day will be approximately 25 liters (vertical scale).

From Technical Report E-P118. Southwest Asia: Environment and Its Relationship to Military Activities. July 1959.

• At temperatures below 38 degrees C, drink 0.5 liter of water every hour.

• At temperatures above 38 degrees C, drink 1 liter of water every hour.

Drinking water at regular intervals helps your body remain cool and decreases sweating. Even when your water supply is low, sipping water constantly will keep your body cooler and reduce water loss through sweating. Conserve your fluids by reducing activity during the heat of day. Do not ration your water! If you try to ration water, you stand a good chance of becoming a heat casualty.

—From Survival (Field Manual 21-76)

Desert Water Sources

Greg Davenport

In the desert, the lack of water plays a major role in survivability. It is an extremely valuable resource and is far more important than food. You can live anywhere from three weeks to two months without food, but only days without water. Thus you need to pack in enough water for at least one day, along with the necessary equipment to procure more. Check with the local authorities on accessible water related to your trip before departing. Don’t rely on someone who hasn’t been in the area recently or is giving you hearsay information. It’s better to adjust or delay your trip than to run out of water . . .

The importance of water in a hot environment cannot be overemphasized, and its availability—carried on you or otherwise—must be continually assessed during any trip into the desert.

The best storage container for your water is your body. If water becomes scarce, do not ration it. Instead, follow these basic guidelines to limit water loss from sweat:

• Work in the evening and morning, when temperatures are lower.

• During the day, rest in a shaded area.

• Wear protective clothing in a loose and layered fashion, with a wide-brimmed hat and neck covering. …

Water Indicators

In hot environments, water may be difficult to find. Map indicators may be misleading, since most desert water is intermittent. Map markings that represent intermittent streams and springs are often relevant only after it has rained, and the windmills, tanks, and troughs shown may be broken down or dry. Understanding water indicators created by plants and trees, insects, birds, mammals, and the terrain will be helpful when trying to find water.

Plants and Trees

Plush green vegetation found at the base of a cliff or mountain may indicate a natural spring or underground source of water. Most deciduous trees require large amounts of water to survive and often indicate the presence of surface water or groundwater.

Terrain

Drainages, valleys, and ground depressions are good water indicators and may hold surface water or groundwater, especially after a rain. Often springs can be found at the base of a plunge pool (dry waterfall) or the bend of a dry riverbed with lush green vegetation.

Natural Water Sources

Since your body needs a constant supply of water, you’ll eventually need to procure water from Mother Nature. Various sources include surface water, groundwater, precipitation, and plants.