Recently I’ve had to answer several questions about purifying water while out camping. So I thought I’d give my thoughts on the subject here.
If you’re going to find a natural source of water for drinking and cooking, it basically comes down to using one or all, of three different methods. Purification tablets, boiling, and filtration.
I’ll go through them in order.
There are several good brands of purification tabs, and apart from residual taste, each one doing pretty much the same as the next, killing off all the nasty organisms that can cause issues. Purification tablets are a very effective way of killing the vast majority of bacteria, viruses, cysts etc. However, what they don’t do is remove the nasties themselves, they get left behind along with any other suspended material.
Which is exactly the same as boiling water does. However, just bringing water to the boil is not enough, to do the job properly you need to leave it on the boil for around three minutes to kill the hardier variety of nasty that can lurk in water, but it’s also very effective at sterilisation.
Water filters however, do have the advantage of removing particulate matter as well as the nasties such as bacteria, cysts etc. Here’s the thing though, while filter manufacturers can’t legally claim to remove viruses because of their tiny size being smaller than the filter can remove. Some filters can remove the host material that viruses need to survive. You see viruses cannot survive in water without attaching to something, and that’s how a filter can remove viruses, by removing the host material.
The problem with filters is that some are better than others. All of the major brands will meet basic minimum standards, but some go far beyond that. Choosing the filter to suit your requirements can be a bit of a headache.
A note on water sources.
Obviously every natural source of water has its own considerations, how clean it is in terms of particulate content, potential infection levels, standing water such as a tarn or lake, free running such as a stream etc, and location, upland or lowland. A little experience can help you a lot here, most of which is common sense, but more on this in another post I think. For now, it is this last point I would like to quickly address.
Free running water from a mountain stream is usually pretty good to go as it is, but any of the above methods will ensure trouble free drinking and cooking. However, lowland water, especially if it’s in an area of arable farming, will almost certainly contain a level of agrochemicals in varying amounts. No amount of boiling, tabbing, or filtering will remove these. I don’t personally think that there is a great amount of danger per se, but it’s certainly worth bearing in mind if you prefer to camp in or around farmland.
Until next time, happy camping.