Bacteria, parasites, viruses, and chemical contaminants all pose problems for human drinkers. Salmonella, E. coli, giardia, and cryptosporidium are some concerning contaminants. If consumed, they can lead to diarrhea and vomiting (which could become deadly).

Melted snow and rainwater gathered in clean containers are generally safe. Things are slightly different if the air is highly polluted. As a general rule of thumb, always use a method of purification to ensure your water is safe to drink.

10 Methods Of Filtering Water In The Wilderness

1. Boil Out Living Matter

When you boil water, you naturally fry bacteria, parasites, and viruses. Boiling water is one of the most reliable ways of purifying water. After you gather the water, you'll have to:


Step 1: Find a receptacle. Ideally, you boil water in a glass, ceramic, or metal container.

Step 2: Consider filtration. If water is cloudy, you may want to strain it through some cloth first.

Step 3: Start a fire. You can start by clearing a space, gathering some brush, and igniting it with a match.

Step 4: Put the container over the heat source. Bring the water to a rolling boiling for at least five minutes. Experts recommend to boil it for twenty, but you may need more time if you are at higher altitudes.

Step 5: Let it settle. Consider letting boiled water settle and removing water from the top to bypass most solid objects. You'll also want to filter the water to remove contaminants.

Step 6: Transfer to a closed container. Keep the newly purified water covered. Otherwise, it can become recontaminated.

If you don't have a glass, ceramic, or metal receptacle, you'll have to makeshift one and perform a rock boil:


Step 1: Find a receptacle. If you have nothing else, use some pine bark to fold into a vessel, a rock depression, or a hide.

Step 2: Heat the right rocks. Heat up some rocks for half an hour. Avoid the use of river rocks or quartz since they can explode at high temperatures.

Step 3: Add the rocks. Put the rocks into the vessel with the water. Keep adding rocks until the water comes to a boil and maintains a boil for twenty minutes or more.

Since boiling removes oxygen, boiled water can taste flat. To improve the taste of boiled water, Try shaking the water up or repeatedly pouring it from one container to another for

You should know how to start a fire under varying conditions. If you don't, or if you have a limited water supply, you might want to choose another method.

2. Eliminate Particles With Distillation

Distillation removes bacteria, viruses, parasites, impurities, and heavy metals:


Step 1: Build a still. Connect the pot for boiling with a sterilized container using a tube. A kettle and a metal tube can heat and transfer clean water.

Step 2: Boil the water. As the water boils, the steam moves up through the tube and into the container. Distillation takes time, but it is a very efficient method of purification.

While distillation cleans the water, it also strips the water of essential minerals. Minerals can be added to the water or made up for by consuming plenty of minerals from food.

3. Distill with a Solar Still

Solar stills collect and distill water:


Step 1: Dig a hole and add plants and a vessel. Dig a hole in a sunny place, and put in materials that contain moisture (like grass and leaves). Put a clean container in the middle of the hole. Add a tube if you're unprepared to disassemble the entire contraption.

Step 2: Cover the hole with clear plastic. You can use a tarp or rain poncho to cover the hole and secure all its sides. The sun shines, and water evaporates. The water rises and clings to the plastic.

Step 3: Put a rock in the middle of the plastic. The rock helps pull the drops of condensation to the middle of the tarp. The water eventually drips into the container.

Water gathered using a solar still is mostly clean.

4. Drop in Some Iodine

Iodine is one chemical you can use to eliminate bacteria, viruses, and giardia:


Step 1: Measure the water. Know how many quarts you have.

Step 2: Apply the iodine. Apply a few drops of iodine per quart.

Step 3: Let it sit. The treated water needs to sit for about 30 minutes.

Step 4: Consider re-treatment. If the water is still cloudy, you will want to add a few more drops.

Even though it is one of the cheaper chemicals, the taste isn't ideal (especially for children). Iodine isn't safe for pregnant women or those with shellfish allergies or thyroid issues.

5. Kill it Off with Chlorine

Chlorine tablets kill most bacteria and viruses. Household bleach of four or six percent can also be used:


Step 1: Measure the water. Know how many liters you have.

Step 2: Apply the chlorine. Use one tablet per liter. If you're using unscented bleach, use two drops per liter.

Step 3: Let it sit. The tablet needs to sit for four hours so it can dissipate. Let bleach stand for an hour before consumption to give the chlorine enough time to kill off giardia and norovirus.

Chlorine tablets are a little pricey, but they don't affect the taste of the water. They do have a long shelf life and are easier to carry around than bleach. On the downside, four hours is a long time to wait, and chlorine is ineffective against cryptosporidium.

6. Let the Sun be your Disinfectant

The sun helps to remove harmful bacteria and viruses:


Step 1: Find a container. You should use glass or PET bottles. You should always try to avoid using PVC. Remove any labels and ensure the bottle doesn't have any scratches.

Step 2: Fill and shake. Fill the container three-quarters of the way and shake it for 30 seconds to activate the oxygen.

Step 3: Finish filling the bottle. Fill the water the rest of the way and cover it.

Step 4: Expose to sunlight. Lay the bottle on its side under direct sunlight for at least a half a day. Experts suggest using a full sunny day. If it's cloudy, you may need to wait for one to two days.

Solar water disinfection (or SODIS) takes time, and if it is raining, this method doesn' work. It doesn't remove sediment or contaminants, so it is more efficient when you use clear water.

7. Use a UV Light Device to Sterilize

Ultraviolet light devices remove bacteria, viruses, and parasites. UV light devices use the power of the sun to decontaminate water:


Step 1: Put the water in the device. The water flows into a chamber where UV light can pass through it.

Step 2: Turn on the device. Bacteria and viruses die in the chamber upon exposure to more ultraviolet light than that provided by the sun.

Manual and electrical water purification devices are available. Hand-cranked versions are more desirable for taking into the wilderness.

UV devices are effective against microorganisms but do not kill some larger pathogens. They also require maintenance and don't do remove metal contaminants.

8. Make a Gravity Filter

Filtration removes bacteria, large parasites, some heavy metals, and sediment. You can make gravity filters in a variety of ways, one of the most common being sand, rock, and charcoal. You can also makeshift a filter made of wood and tubing:


Step 1: Find some pine sapwood. You need one cubic inch of pine sapwood, some hose, and a binding agent.

Step 2: Peel the bark and add the hose. Peel the bark and put it into the tube. Use some epoxy to keep water from going around the bark.

Step 3: Put water in a sterile container. Multiple quarts pass naturally through the wood and into a clean vessel.

Most bacteria get eliminated, but filtration is not the same as purification. While it removes bacteria, it is ineffective against viruses.

9. Suck on a Survival Straw

Survival straws remove bacteria and are great for individual use. It easy to operate and compact to be stored.


Step 1: Hold the straw above the water. Hold the straw here for about a minute and allow the water to rise up through the straw.

Step 2: Drink the water. Voila. The water is filtered.

Survival straws can't process too much water at a time. It's always better to have one on reserve for emergency situations.

10. Carry a Portable Pump

When you put unclean water through the ceramic or charcoal in the pump, the pump cleans the water. You can even get water bottles with a built-in pump.

Step 1: Set up device. Depending on the device, follow the instruction manual prior to bringing it out doors to get familiar with the device.

Step 2: Place the tube ends into the correct water source. Put the source tube into a wild water and the other safe end into a drinking container.

Step 3: Pump pump pump. Each pump will roughly provide you a mouthful of water depending on your portable water filter.

Step 4: Water is ready for drinking. The water is filtered and ready to be consumed.

Pumps are effective if you have the time to stop and set it up. However, they don't guarantee the removal of all bacteria or viruses.

Bottom Line

There are many ways to make water more palatable and safer to drink. Distillation and boiling are some of the best methods of purification. Survival water filters are great because they are compact to store and easy to use for filtering out harmful chemicals in the wild.

Portable water filters are not as time consuming as most of these methods, but it's always better to learn how to purify water in the wild in case of an emergency. Few methods remove all harmful bacteria, viruses, impurities, and chemical contaminants. If you have time and resources, try using a few different way to familiar yourself with the purification and filtration process.