8 Ways To Purify Water In A Pinch (Key Survival Skill) (2022)

Forest with a river running through it.
Table of Contents

    When you’re out on a camping trip or exploring in the wild, it’s vital to have a reliable supply of fresh water. Outdoor activities are a lot of fun, but they can be strenuous and highly dehydrating. Running out of water out in the backcountry can be very dangerous, so you need to know how to purify water in a pinch. Fresh H2O is one of the most important supplies to bring camping, and knowing how to source your own is a key survival skill. 

    If you’re going on a shorter trip, you can carry all the drinking water you need in from the outside. Check out our article on how much water to bring camping to find out all you need to know about packing in your hydration. However, those on longer camping trips would need to carry an enormous amount of liquid, as most campers need three liters a day. Additionally, there are plenty of emergency situations where you could easily become stranded without water. For these reasons, it’s paramount that everyone learns how to purify water so that it’s safe to drink. 


    A water tap.

    You don’t always have access to safe water out in the wild.


    Why purify water? 

    You might think that mountain streams and natural springs are an ideal source of hydration, but unfortunately, contaminated water is everywhere. Even if the source looks clean, you never know what water-borne nastiness could be filtering into the water upstream. Drinking from an unclean water source puts you at risk of all sorts of diseases and parasites, risking your camping trip, and potentially your life. 

    Cholera, parasitic worms, giardia, protozoa, cryptosporidium, and any number of viruses could be contained in dirty water. It doesn’t matter if the source is a river, stream, spring, or pond; you should never drink water from an unknown source. There are plenty of ways you can disinfect a small amount and benefit from safe drinking water. Now you know the risks of consuming contaminated water, and why disinfecting water is a vital survival skill, let’s find out how you can find your own hydration outside. 


    Finding a water source

    Before you can purify your drinking water, you need to locate a source. The availability of water depends on your environment, as there are many potential sources of cleanable water. Freshwater sources such as streams and creeks are ideal as they are running water, but lakes and ponds can also suffice. With certain disinfection methods, you can even distill brackish or salty sea water. 

    Rain, snow, hail, and ice can all be potential sources of drinking water. New and untouched snow, as well as fresh rain which didn’t fall through tree canopies, can most likely be considered safe to drink without any purification necessary. However, you may still want to use one of our methods for peace of mind. Underground springs are often clean water sources, but there’s no sure way to identify the few which are contaminated. We recommend using one of these 8 ways to purify water no matter the source, to ensure your camping trip is completed safely. 


    8 ways to purify water in a pinch 


    1. Boiling 

    One of the oldest water purification methods available is the act of heating water until it reaches a rolling boil. Boiling cannot remove all forms of chemical pollution, but it’s a reliable disinfection method that will kill off most parasites, bacteria, and other pathogens. Heating water will also not remove any solid contaminants and particles from your drinking water, so you may also want to combine boiling with a water filter to complete the purification process. You can use a coffee filter to remove a large proportion of particles suspended in dirty water. 

    You can boil your water in a clean container made of metal, ceramic, or glass. Most people use either a campfire or camping stove to provide heat. Five minutes of boiling time is enough to kill most water-borne organisms, but keep your water at a rolling boil for 10 minutes to be completely safe. If you’re camping at a high elevation that could affect boiling and cooking times, you may need to extend this further. 

    To boil and purify water so that it’s safe to drink, collect it in a suitable container. Set it over your flame to warm up, it will first heat and then begin to simmer. A rolling boil is when bubbles are furiously rising from the bottom of your container, this is the hottest temperature at which you can heat water. Maintain this boil for at least 10 minutes, after which your water should be disinfected and safe to drink. 

    Boiling water isn’t the perfect solution to turn a natural source into a safe supply. While it will kill most bacteria and live organisms, this purification method is completely ineffective against pollutants, chemicals, and heavy metals. The fact remains that boiling water is likely the easiest way you can source drinkable water out in the wilderness. You can even do it without a container; heat some rocks for 30 minutes in a fire and set them into your water container. You can use a rock depression, folded piece of bark, animal hide, or anything else you can think of. 


    2. Bleach 

    There are several chemical treatments that can be used to purify water. In the same way as boiling water, there are several household chemicals that you can use to disinfect water in a pinch. One such chemical is bleach, or sodium hypochlorite, a product based on chlorine which is often used to disinfect swimming pools. Chlorine is also the chemical used to keep city water supplies safe, so it’s a good choice to clean your drinking water. 

    Bleach isn’t 100% effective as your water will still need filtration. Additionally, bleach does not kill the microscopic parasites cryptosporidium or cyclosporin. You’ll need to carefully measure the quantity of bleach you use to disinfect water, as we all know this chemical can be dangerous to humans if you consume too much. However, just a few drops should be safe enough to kill pathogens without harming you. 

    If your water source is cold or murky, use four drops of bleach per liter or per quart of water. Clear or warm water only needs two drops to be effective. After adding your bleach, replace the lid on your water container and shake the mixture thoroughly. After a minute, turn your bottle upside down and slightly unscrew the cap. This will allow a small amount of bleached water to escape through the gap, cleaning the thread and inside of your container. 

    After re-tightening your bottle lid set it in the shade for 30 minutes. Once the time has passed your water bottle should smell like chlorine. If you don’t notice this distinctive scent, add another two drops of bleach and wait another 30 minutes for purification. The waiting time is a definite downside of using bleach to disinfect water, but it’s worth it to be sure your supply is safe. Certain water-borne dangers such as norovirus and giardia need longer than the standard 30 minutes to kill, so it’s always better to be safe than sorry. 


    Bleach and other products.

    Bleach and other chemicals can be used to disinfect contaminated water.


    3. Iodine Tablets

    Another form of chemical purification which works great to clean water for drinking is iodine tablets. Iodine is a common household chemical that you could use in the same way as bleach, but it’s much more dangerous to humans. A few drops of bleach won’t do you any harm, but make a miscalculation when measuring out your iodine and you could suffer dire consequences. 

    Luckily, there’s a purpose-made solution that allows us to use iodine to clean water without endangering our lives: water purification tablets. These are convenient to carry and come in pre-measured doses, so all you need to do is drop in the right number of tablets. Campers, backpackers, and travelers of all kinds often carry these small and lightweight emergency supplies, so they will always have safe drinking water in a pinch. All you need to do is let them dissolve in your water container and wait for the allotted period of time before your water supply is safe and ready. 

    As with boiling and other forms of chemical disinfection, iodine tablets cannot filter your water. That means you need to combine this purification process with a coffee filter at the very least to remove any particulates from your drink. Other more advanced filtration options are available; it all depends on the supplies you brought along. One important note to remember is while you can combine chemical and physical cleaning processes, you should never use iodine and bleach together. You can also buy water purification tablets made from chlorine dioxide, which work in the same way to make your water safe. 


    4. Water Filters

    Another way to turn dirty water into a safe form of hydration is filtration, a quick and straightforward purification technique. Water filters are cheap and portable and can remove many dangerous contaminants. They work by letting water flow (or pushing it with a pump) through blocks of activated charcoal and carbon filters. These materials absorb chemicals and contaminants as the water flows through, so clean filtered water comes out the other side. 

    The pore size of water filters is measured in microns and determines what size particles will be filtered out. The standard size is 0.2 microns, which will block heavy metals and large parasites. However, viruses are not affected by filtration. Active carbon filters are far more effective at removing chemical contaminants than boiling or chemical treatments, they’re much more effective for polluted water. These filters will even remove the chlorine taste from your tap water. 

    If you want to filter water on the road, check out the best devices for backpacking. This buying guide will take you through the best filtration systems so you’ll always have clean and clear water. You can perform simple water filtration to remove larger particles with a coffee filter, but use a specialized filter to ensure you stay healthy. 


    5. Distillation

    In disaster situations, it’s possible that all water in your area becomes heavily contaminated. Radiation, lead, salt, and heavy metals are among the many dangerous contaminants which will destroy your water filter and make you sick. In this case, your best option for purifying water is distillation. This is the only purification process that you can use to remove radioactive contaminants, although it’s ineffective against certain contaminants including certain organic compounds. 

    Distillation helps remove heavy substances, it can even make saltwater drinkable. You can create your own solar still to harness the sun’s energy to clean your water; the concept is fairly straightforward. Dig a hole in the sun and fill it with the water you want to clean. Set a clean container in the center, and then cover the whole thing with a plastic sheet. Ensure the sheet is completely sealed around the edges and place a rock in the center, so the sheet points downwards towards your empty container. 

    As the sun heats the dirty water, it will evaporate and collect as condensation on the inside of your plastic sheet. Then, gravity will pull the clean water droplets downwards towards the rock, where they will drip into your container. This is the best water treatment option in a situation where the only option is heavily contaminated water supplies. If you want truly purified water then water disinfection is also necessary. 


    A man filtering water.

    Advanced water filters are a great way to make water drinkable.


    6. Water Purifiers 

    Purifiers are similar to water filters in the way that they work, but they can also remove viruses and smaller pathogens. Water purifiers usually contain carbon filters as well, meaning they’re one of the most effective ways to get treated water on the go. Check out the best camping water purifiers to find out more about these amazing pieces of technology. 


    7. Ultraviolet Light 

    Ultraviolet light is a powerful force, one which can be very damaging to humans if we’re not careful. Through the same process which burns our skin when we stay in the sun for too long, UV radiation can break apart the DNA of pathogens in water. UV light from the sun can do this, but Ultraviolet water purification devices can complete the process much faster. 

    UV purification systems produce much more UV light than the sun, meaning they can kill viruses and bacteria instantly. These systems are actually more effective at killing certain viruses, including norovirus and hepatitis, than chlorine disinfection. The more powerful the ultraviolet device, the easier it can kill off pathogens. However, there’s a downside to this form of water purification. 

    UV water filters have no effect on heavy metals or particle contaminants, so the purified water can still be dangerous. We recommend using a filter on UV treated water, so you can be sure that all contaminants were removed. Ultraviolet filters need to be cleaned and changed regularly, so they’re also a more high maintenance option. 


    8. SODIS

    Solar Water Disinfection, or SODIS for short, is the more natural version of UV water treatment. Both use the same technology, but the sun’s energy is completely free and takes one to two days to purify water. If you’re in desperate need of a quick drink, then this purification technique is not for you. However, if you have the time, SODIS is easy and surprisingly effective. 

    You can use solar disinfection by filling regular clear plastic bottles with dirty water. Then, you leave them to sit in the sun for at least one full day, so that UV rays can kill the hazards within. This method is not guaranteed as SODIS cannot be 100% effective against all pathogens, however, it’s a great emergency survival technique. 

    There are a few failings to using the sun as a disinfectant; firstly, overcast days will double the time period your water bottle needs to sit. Glass bottles are also not as effective, and contaminated water which isn’t clear is also harder to purify this way. A maximum of 2 liters of dirty water can be clean in this way in one plastic bottle. 


    Empty plastic bottle by snow and water.

    There are so many ways to purify water, even with a simple plastic bottle.


    Final Verdict:

    Knowing how to purify water is an important survival skill, one which every camper should learn along with building fires and emergency shelters. Finding clean and drinkable water out in the wilderness is difficult, but one thing which will make it easier is knowing how to test spring water. After testing, you can use one of these 8 ways to purify water, which work in a whole range of environments and situations. Now you know how to create clean drinking water in a survival situation, and are better prepared to tackle the outdoor world. 


    Bonus tip: While you’re at it, check out this awesome video on how to make a solar still!



    Riley Draper

    Riley Draper is a writer and entrepreneur from Chattanooga, Tennessee. As a world traveler, he has been to more than fifty countries and hiked some of the most elusive trails in the world. He is the co-founder of WeCounsel Solutions and has published work in both national and global outlets, including the Times Free Press, Patch, and Healthcare Global. When he's not writing, he's probably on a hiking trip or climbing in the mountains.