Water Purification - Survival Kit Series
The water in New Zealand is pretty good. Mountain streams and rivers are a fairly safe bet for drinking, but they shouldn’t be taken for granted, and outdoors people should have a lightweight water purification system as a backup.
While most hunters and hikers are perfectly happy to drink straight out of our waterways, the safest option is to purify every time you drink in the outdoors. All it takes is a dead possum upstream to cause you some serious gastric discomfort or even put your life at risk.
When hiking in places like the Coromandel – where waterways pass through farmland and can also be infected by escaped livestock – it is essential to purify water. And in most other countries backcountry water sources can’t be trusted at all. In some places even the tap water needs to be purified.
So what is the best way to purify water?
The surest method of purifying your water is to boil it. If you’re camping with a gas cooker or open fire, it doesn’t require any extra equipment. People will tell you different things about how long you need to boil water, one minute, three minutes, even as long as 15 minutes. In reality, you just need to bring the water to the boil. This will kill just about everything. It won't, however, remove toxins or chemicals which may be present.
The downsides to this method are obvious. If you’re moving quickly it’s a pain to stop, set up a cooker, wait for the water to boil, and then wait another half an hour for it to cool enough to put in a bottle. Then you have several hours of drinking hot or warm water, which is no fun in the summer.
This is where water purification systems come in. Most work almost instantly.
A simple and popular option is water purification tablets. These are really just for short trips or emergencies. They work quickly and effectively but they often give the water a bit of a chlorine taste. You can purchase better-tasting pills that use other chemicals such as iodine. In any case, if you use them continuously they will start to take a toll on your health.
UV water purifiers are very quick, they don’t change the taste of the water, and they scramble the DNA of any little buggies in your water so they won’t reproduce and poison you. But these devices require a battery, and they tend to be a bit delicate. There’s nothing worse than getting caught on a long hike in a foreign country with a broken purifier.
Carbon filters are an excellent option, especially for camping. As well as removing bacteria, they take out dirt and sediment and actually improve the flavour of the water. It’s entirely unnecessary, but for those extra-careful types, filters can be used in conjunction with tablets and will remove a lot of the chlorine flavour. Many filters won’t be convenient for hiking, as they can weigh up to 1kg.
Filter straws are a game-changer. They are very lightweight and compact. They remove nasties from the water and improve the taste, and they are designed to filter thousands of litres before they wear out. The best part is, they’re cheap. A filter straw costs about the same as a pack of tablets, and will last much longer. You can clip it onto your pack or tuck it in your pocket to use whenever you get thirsty.