This video covers different methods for treating water using filters, purifiers or chemicals and how they apply to backpacking.
The following article examines water treatment methods for backpacking. There are generally five ways to treat your water while on the trail: through water filters, water purifiers, UV light, chemical treatments, and of course, you can also boil your water.
With filters and purifiers there are a couple of different options. In the video above, our Gear Specialist features a model with a synthetic cartridge. Filters of this style usually pump water very quickly, so you get a lot of water output for not as much work time. The down side is they are not field-maintainable and they tend to clog faster because the synthetic material is not able to be cleaned; it must be replaced.
Also shown is a ceramic style filter, which is basically made from a piece of clay. These filters pump a lot slower than synthetics, though they are field-maintainable. Using a scouring pad, you can scrub the outside and clean off any dirt that's built up before putting it back in the case and starting to pump water again. They are reusable in the way that synthetic cartridges are not, though they are a little bit more brittle and delicate than a synthetic. As is the nature of ceramic material, it can break if dropped or become damaged if frozen.
Among water filters and purifiers, there is a third option that offers the best of both worlds in combining ceramic and synthetic components. In the model shown, there is a ceramic filter in the top, as well as, a synthetic filter underneath. There are also models that allow you to back-flush them. What that means is you can rearrange how the system works so the water is going the opposite direction and forces water back through that filter system and cleans up some of the built-up contaminates in it, which extends the life of the filters.
UV light is another form of water treatment, and this is a technology that is frequently used in urban municipalities to treat large quantities of water, so it's not just an application that's being used for backpacking. The model shown consists of a lamp that the UV light comes through, which can be very delicate. Most models come with a protective covering to keep the lamp safe from breakage. The upside to these models is that they are extremely small, compact and lightweight. They also treat your water for different forms of bacteria, protozoa and viruses. The downside to UV lights is that they run on batteries that are going to need to be charged or replaced after multiple uses. UV lights also don't give you an option with just the unit by itself for cleaning particulate matter out of water, which would be things like leaves, mosquito larvae and other “chunky stuff” that may be in your water. Before UV treatment, you want to strain your water or run it through a pre-filter of some sort.
Chemical water treatment options have some benefits and drawbacks just like other methods. The main benefit is that they are very affordable. They're also very lightweight and barely take up any space in a pack or emergency kit. The down side is that you typically need a lot of any given chemical to treat significant volumes of water, especially over an extended backpacking trip. Additionally, a prolonged period of time is needed for chemical water treatments to break down viruses and other bacteria and contaminates in the water.
Chemicals used in treating water include iodine, which is extremely common and has been used frequently by backpackers in the past. Iodine does have a bad taste, and there are studies that show long-term side effects to using it over extended periods. Quite a few people are also allergic to iodine. Another good chemical option would be something like Katadyn MicroPur tablets. These products are based on a chlorine treatment that's really similar to what you might find in your tap water that’s been treated by a municipal water authority. This chemical treatment has very little taste and is also affordable and lightweight.
The final water treatment option is plain old boiling of water, which will remove almost all of the harmful things from your water and can be used in conjunction with all of the other methods discussed. Boiling water isn’t always practical, but it is the most “low tech” way to treat water.