You can only survive a few days without water in most cases, and sometimes not even that long. Knowing how to find and purify water is vital in a survival situation.
Necessities:
Optional:
Start by learning how to do the following:
Once you have mastered these skills, you should learn how to do the following:
Assume all surface water is contaminated and requires purification, and if you have to choose a water source, try to find running water. To avoid getting sick or becoming dehydrated quickly, avoid drinking alcohol, saltwater, stagnant water, urine, or eating snow.
At 70°F (20°C), you will need around 2 to 3 quarts/liters of water daily. This amount increases with physical activity and exposure to higher temperatures.
Dehydration occurs when the body loses more fluids than it takes in. Symptoms include thirst, dry mouth and throat, fatigue, dizziness, dark urine, reduced urine output, dry skin, headache, and confusion.
You can find water in many places if you know where to look. Unless otherwise stated, you should purify all water that you collect.
Rainwater collected directly in containers does not need purification, but it should be purified if it has touched another surface. Snow and ice should be melted using a fire or body heat before drinking; eating it directly can lower your core body temperature.
Flowing water from rivers or streams is typically safer than lakes, ponds, and stagnant water. Saltwater can be put into a solar still to remove the salt and should never be consumed directly.
Water is available in many places by just digging a hole in the ground and allowing water to seep in. You can find groundwater in dry environments by looking for green vegetation, valleys, low areas, or dry riverbeds.
Plants can provide water when no open sources are available. Look for green bamboo, vines, or coconuts for easy access to water, but be sure to positively identify the plant before consuming. You can extract water from other plants by placing them into a solar still.
Dew can be collected from plants in the early morning using a cloth to soak up the water. Only collect dew from plants you can positively identify as safe.
Solar stills produce small amounts of water and are best used as a supplement.
Below-ground solar still
A below-ground solar still is a simple device that uses the sun's heat to draw moisture from the soil or plants. The moisture then condenses on a plastic sheet and can be collected in a container.
Transpiration bag
A transpiration bag is a plastic bag tied around a leafy branch to collect water. Use multiple bags to increase yield.
Always ensure the water you collect is safe to drink. Boiling is the most reliable method, but chemical purification tablets and filters are also effective. If you cannot purify the water immediately, prioritize finding and storing water until you can treat it.
Bring water to a rolling boil for at least one minute. At higher altitudes (above 6,500 ft / 2,000 m), boil for three minutes. If you do not have a single-walled metal container that can be used for boiling, then do the following:
Use a portable water filter to remove contaminants. Some filters are rated to remove nearly all bacteria and viruses and can be used without additional purification. Custom-crafted filters are less effective and require additional purification.
A filter will have an inlet and an outlet, and it typically shows the direction of water flow with an arrow or text (inlet to outlet). Place the inlet into the dirty water and the outlet into a container, then pump to filter the water. If you are using a filter straw, the outlet goes into the water and the inlet into your mouth. Be careful never to let the outlet come into contact with unfiltered water. After filtering, you can remove the inlet from the water and pump a couple of times to push out excess water. With a straw, forcefully blow into it to clear out water.
If the manufacturer's instructions are different, be sure to follow them instead.
Chemical water purification tablets or drops can be used to treat water. Be sure to follow the instructions, which are normally printed on the bottle. The most common chemical is iodine, but chlorine-based treatments are also available. Before deciding which to buy, research how effective they are against bacteria and parasites in your region. Treatment amounts and times vary by chemical type and brand. Be sure to check the expiration date (if any) before going on a trip.
If you are pregnant or have thyroid problems, don't use iodine. Always read the warnings on the packages of chemical purification solutions before buying them.
Here are some general steps for iodine tablets if you lost the instructions (based on the most popular brand, Potable Aqua):
Conversions
The following conversions are approximate, but that is fine for purification.
As a last resort, you can use sunlight to purify water in a clear water bottle.
Water may contain bacteria, viruses, and parasites that can cause illness. Boiling water kills most microorganisms, but some may require additional treatment. Microorganisms are more likely to be present in stagnant water.
Water may contain chemicals from industrial or agricultural runoff. Purification methods may not remove all chemical contaminants. Avoid drinking water next to roads, farms, or other inhabited areas.
A wooden bowl can be used to boil water using hot rocks.
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Instructions
You can use tongs to move around hot coals or rocks without getting burned.
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Instructions
A crafted filter can be used to remove sediment from water, but it will still require additional purification.
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Instructions