5 Methods Of Water Purification


We all know that water is essential for life – it’s just one of those no-brainers. But what if our water supply were to stop or get contaminated as a result of something like a natural disaster? Think Hurricane Katrina. How would you turn that dirty, unpotable water into drinkable, thirst-quenching hydration? In this article, I’m going to focus on 5 simple ways to purify water.

All water must, whenever possible, be purified (sterilised) before consumption as waterborne diseases and parasites can cause mild to severely debilitating illnesses which could potentially stop you from functioning physically and even kill you.

Obviously, if there is no way for you to purify water then you should at least filter it a number of times before drinking. Having an upset stomach is better than dying of dehydration in my opinion.

Be aware that any water contaminated with chemicals cannot be made safe to drink by any purification method. Never drink water that is contaminated with chemicals.


The simplest and perhaps the most well-known way to purify water is by boiling it for one minute. This will kill all dangerous pathogens. Boiling water for anything longer than a minute is a waste of precious fuel and water as the evaporation of water at high temperatures is huge. Of course, you know that you’ll need a suitable container and a fire to do this. I use an army issue canteen cup but you can use a metal pot, billy, a non-insulated stainless steel water bottle and even a plastic bottle or bag (I’ve done it). It is a good idea to clarify (pre-filter) the water to remove sands, sediments and other objects using a piece of cloth before you boil it.

Chemical Treatment

Another method of purifying water is treating it using chemicals such as potassium permanganate (aka Condy’s Crystals), iodine, hydrogen peroxide and even your common household bleach.

Some of these chemicals are sold in ready-to-use tablet form and are advertised as “water purification tablets”. These are available at all good camping stores and a plethora of online camping, survival and emergency preparedness vendors. A couple of brands that I would recommend are Katadyn Micropur tablets, Potable Aqua and PuriTabs. They are quite easy to use. Simply, drop the correct number of tablets into the water requiring purification (usually one tablet purifies one litre of water) and then wait for the recommended amount of time before consumption. Most tablets take 30 minutes to work their wonders. Be sure to always read and follow the instructions on the tablet wrapper before use.

My favourite chemical for treating water is Condy’s Crystals (see my article on some of its marvellous survival uses). To do this simply add 3-4 crystals to every litre of water, stir or shake and let it sit for 30 minutes before drinking. Condy’s kills harmful viruses, pathogens and bacteria such as Giardia lamblia and Cryptosporidium. The water will be a light tinge of pink but should not be any darker. Remember the rule “If it’s pink, then it’s OK to drink.” If it’s purple then its for your feet (as an anti-fungal treatment).
To use your standard household bleach to do the job, add 2 drops of bleach to every litre of water and let sit for 30 minutes before consuming. Make sure that you use regular, no-frills, unscented bleach.

Likewise, iodine can be used to do the same thing. Add 5-10 drops of 2% tincture of iodine for every litre of water and let it sit for 30 minutes. Just make sure that you or anyone else who may consume the water treated using iodine does not have any allergies to iodine.

Commercial Purifiers

There are many different brands of purifiers available on the market. Purifiers are quite easy to use and filter out harmful bacteria, cysts and viruses found in unportable water. All of them operate in a similar fashion. Basically, the undrinkable water goes up a little hose into one end of the purifier and goes through a ceramic or charcoal filter before coming out the end of another hose. Some are pump operated whilst others are simple filter straws.

UV Light

Ultraviolet water purification is the most effective method for disinfecting bacteria from the water. Ultraviolet (UV) rays penetrate harmful pathogens in the water and destroy illness-causing microorganisms by attacking their genetic core (DNA). Check out our review of the best portable UV water purifier – click here.

Solar Still/Distilling

  • This method relies on direct sunlight and is one great way to make unpotable water micro-organism free and safe to drink You can even distil your urine in an extreme situation!
  • Dig a hole or pit in the ground
  • Put a container in that pit/hole to collect condensation from the solar still
  • Cover the hole or pit with a large, transparent piece of plastic sheeting or a garbage bag. Place small rocks or stones around the pit/hole to hold down the sheeting.
  • Place a rock or some other heavy object at the centre of the sheet

Bonus Tip: Add some vegetation into the pit/hole to increase the water output. The direct sunlight on the vegetation will cause it to sweat and the resultant condensation will be collected by the container.

Whatever method you decide on using, remember to pay attention to your body’s signs. Are you becoming dehydrated? If so, make sure you put water back into your body as soon as possible. Advanced dehydration can lead to what is known as ‘dehydration dementia’ and this can cause you to behave irrationally and make poor decisions. The colour of your urine is the best way to determine whether you’re adequately hydrated or not. If it’s pale then that means you’re good to go if it’s the exact opposite then you should be getting fluids into your body ASAP. Oh and another tip: “Drink don’t sip your water!” Sipping water is perhaps one of the single biggest killers in the outdoors. Your sips only get to your organs but not your brain where it is needed most.

I think that just about covers everything. If there are other methods that I have left out in this article, feel free to add them in the comments below.

Kevin Noyes

Hey there, I'm Kevin, a former infantry soldier in the U.S. Army. I've been through it all - from grueling training to intense combat situations. Now, I'm here to spill the beans on survival. None of that dry, textbook stuff - I'm talking real-world, practical tips to help you conquer any wild situation. From setting up camp to keeping your cool, we'll tackle it all together! So let's dive in and get ready to rock the survival game!

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