How to find clean drinking water in the wild: 8 top tips

Tips, tricks and techniques to finding drinking water in the outdoors

woman scooping mountain water from a pool
(Image credit: Getty)

 Most of the time we’re lucky, and clean, drinkable water is just a twist of the tap away. So much so that most people don’t think about it at all in their daily lives. However, once you’re outdoors on an adventure the need to have clean water – and several litres a day at that – becomes suddenly more of a challenge. 

Carrying it with you in one of the best hiking water bottles is one solution, and for shorter trips that’s a practical scheme. But for longer or more remote ventures, what do you do? There are a few different ways to purify water in the wild, and if you've had the foresight to invest and pack one of the best water purifiers, you're sorted. But if you know your stuff, you won't even need to follow that additional step, as some water is perfectly safe to drink straight from the source. Here's exactly how to find drinking water in the wild.

1. Local knowledge is the key

The best water sources are ones that are already known to be clean, so local knowledge is the most important way to find clean water. Depending on the area, there may be marked springs on maps, or local experts that can clue you in to the best spots. 

2. Look for human evidence

Water sources that are well-used by humans will often have some kind of easy access system, not necessarily as obvious as a bucket by a well, but in the mountains a pipe might have been added to a stream to divert water, or a spring modified with rocks and a scoop. These are all very good indications that you’re not the first guinea pig to drink here, and the fact it was worth someone putting in the effort means it’s pretty much guaranteed to be good water. 

3. Look for animal evidence

While animals leave a different type of evidence around good water sources, there’s still plenty of it if you look. Multiple hoofprints in the soft mud around a stream, well-worn trails leading to a lake or river are all good indicators that a spot is popular with the wildlife, and thus not a bad shout for you too, although that’s not 100% guaranteed. If you’re looking at a larger body of water, like a lake or river, then aquatic animals can be a good indicator of water quality. 

Brown trout darting through the shallows of a clear river laden with healthy green water plants indicate a healthy environment, for example, and one you might consider gambling on drinking. A murky pond with scum on the surface or a suspicious odour and no visible animal life may well be contaminated, and should be avoided if at all possible. 

4. Fast flow good, no flow bad

If there’s no obvious evidence either way, you’ll have to evaluate a water source for yourself, the best rule of thumb is that fastest flowing water is better than slower flowing, and still and stagnant is the worst. The old wives tales of dead animals in the river upstream might possibly be true, but very unlikely on balance. If in any doubt, heading upstream will get you better, cleaner water, so following up a mountain stream is a good technique. 

5. Let the terrain guide you

Mountain streams may not all be marked on maps, but the lower, larger rivers and streams will be, so paying attention to the geography and terrain will serve you well - a steep sided mountain valley with a river at the bottom is likely to have streams running down to it. Equally, if in dire straits for water, it will collect at the lowest point, so going low will definitely find water - just it may not be the best to drink!

6. Dig for victory

If you have the means to filter the results then digging is a sure-fire way to find water. Find a boggy area, and/or one with unusually lush vegetation, and dig a hole. This should soon fill with groundwater, which might be muddy and unpalatable, but once filtered should be drinkable. A simple sand-based filter will remove mud and debris in a pinch, but not parasites or contaminants. 

7. Above the snowline

Mountain streams are usually pretty safe to drink, thanks to a lack of human pollution high up, but if you’re above the snowline the obvious choice is to melt snow to drink. If you have a stove then melting enough snow to drink is relatively simple - just add snow gradually to a pan and you’ll have tea in no time. Another technique is to add small amounts of snow to your existing water bottle and keep it warm inside a jacket or tent, although this is a much more intensive procedure. 

Choose nice clean snow to melt, never tainted with any colour (especially yellow!), and ideally fresh powder from the very top layer. This should be new, and uncontaminated by contact with the ground, animals and passing humans, etc.

 8. Look to the skies 

One of the easiest ways to collect good quality drinking water is to catch rainwater, which needs little more than a container and a wet day. This can be scaled up in many ways to suit the situation, and is relatively hassle free, although not necessarily practical on a hiking holiday. 

Mark Mayne has been covering tech, gadgets and outdoor innovation for longer than he can remember. A keen climber, mountaineer and scuba diver, he is also a dedicated weather enthusiast and flapjack consumption expert.