How to Purify Water in the Wild

Rainwater

If none of these options are available, our next go-to is to collect water from the rain. Rainwater is a perfect option because it is unlikely to carry bacteria. The first and most obvious option is to place all the containers you have out to catch the rain as it falls. To be more efficient, you can use a tarpaulin or other plastic sheet to collect the rain and funnel it into a container. Tie the corners of the plastic to some trees and use a stone to create a low point from which the water can drop.

Aside from rainfall, you can also find water in low areas where rain accumulates. This could be a tree crotch or a rock crevice. You can use an absorbent material, as you did with the dew above, to collect the water and wring it out to drink it.

Making a container from birch bark

If you don’t have a container, you can make one out of birch bark.

Sometimes there’ll be no rain available, but there will be snow. The first thing you must remember is that you always need to melt the snow. If you eat it cold, it requires a lot of energy to heat our bodies up again. So how do you do this?

The first and most obvious option would be with a small fire or similar. If you don’t have this option, you can use the heat of the sun with the snow inside some kind of container. Alternatively, you could also try to find snow that is already being melted by the sun and collect it. This usually happens on dark colored rocks.

Digging

If there is no water source available, another option is digging. In this video, you can see how he uses a big, flat rock to dig into a dry river bed looking for water. After finding damp sand, he then uses a stick to move the sand and his hand to take it out of the hole. After about half an hour digging he reaches water, and uses about an arm’s length of plastic tubing to suck the water out of the hole.

Cleaning water

Now that you have found a water source, how can you make sure that it is safe for human consumption? In reality, none of the methods below are 100% safe. It may well be worth combining more than one to get the purest water possible. Either way, they are all a better alternative than suffering from severe dehydration.

Although primitive water filtering techniques are impressive, it’s best to stick to more efficient techniques.

If you can take some equipment with you when you leave, you could think about taking a steripen, bleach or iodine.

A steripen

The steripen uses UV light to purify the water and make it safer to drink. You put it inside the water, turn it on, and stir for about a minute. The main limitation of this method is that you can only purify about a bottle of water at once. It’s still a fast way to get something to drink.

Bleach

You also have the bleach option. Add about 5 drops per liter of water and leave for about an hour. Surprisingly, most of the living bacteria in the water will have been killed off by the bleach, and it is safe to drink. Remember to make sure your beach is free of perfumes, dyes, and other additives.

Activated charcoal

Using activated charcoal to purify water is a technique which is said to have been used in Japan since the C17th. Nutritionist Miguel Toribio-Mateas says that activated charcoal can be useful in purifying water as it removes harmful solvents, chlorines, and sediments, as well as making the water taste better. There is even evidence of it being able to help with some bloating. This charcoal is available in sticks that you pop into the water you want to purify. The longer you leave it in there, the more metals and toxins it is likely to adsorb. Between 24 and 48 hours seems to be a good start.

Boiling

If you haven’t got this equipment, the safest way to remove harmful bacteria is…yep, you guessed it, boiling the water. It’s been used as a water purifying method for centuries and continues to be one of the most popular.

In an article on the importance of water purification, the United States Environmental Protection Agency advises us that we should bring the water to the boil and “keep it rolling for one minute to purify it.” We are also advised that “at altitudes above one mile/2,000 meters, you should increase the rolling time to three minutes”.

Filtering your water

If your water is cloudy, filter it before starting the boiling purification process. Good options for filtering include something as simple as a T-shirt.

If you’re in a cold environment and can’t use your t-shirt, you can make a natural filter. You need moss, charcoal, sand and a plastic bottle. Start by cutting the bottom of the bottle off, making holes in the screw cap, and placing it upside down in a stand. Push about an inch of the moss hard into the bottle first, then the ground charcoal, then sand, then more charcoal. Alternate between these two materials until you are close to the top. Then add a final layer of coarse sand with small rocks in. Pour the water in slowly, and remember that the first and maybe even the second run-through will still be dirty.

The Xylem filter

If boiling water isn’t an option, but you do have pine trees near, you’re in luck because you can use a xylem filter. Researchers at MIT have discovered that by cutting off a small section of pine branch, removing the bark, and placing it inside a tube, they can create a filter. It works by allowing the water to pass through tiny membranes in the xylem tissues. This filter is capable of purifying 99.99% of bacteria (although not viruses as they are smaller) and several liters of water per day.

The Sawyer Filter

If you’re keen on a foolproof, high-tech solution, Sawyer offers an excellent mini-filter that weighs two ounces and will clean as much as 100,000 gallons of water, removing 99.99999% of all bacteria, such as salmonella, cholera and E.coli, removing 99.9999% of all protozoa (such as giardia and cryptosporidium), and removing 100% of microplastics:

Definitely a worthwhile addition to your travel pack.