Disclaimer: Through my experience and study, there is no “right” answer to the best way to treat your water in the backcountry. Without getting too scientific, my purpose in this discussion post is to explain the basics and give you a starting point when deciding what will work best for you. Each region of the U.S. is different as well as each country, so it’s best to research the water in the area before traveling to that particular place.
Chances are, if you’re going for a day hike you’re not going to have to worry about finding water in the backcountry, but even a short hike can turn into an emergency. Would you be prepared? There’s so many types of purifying and filtering systems out there it may feel a bit overwhelming. Do you even need a purifier? What’s the difference between purifying and filtering anyway?
Filtering: Depending on the filter, it generally works against protozoa and bacteria but it’s not effective against viruses.
Purifying: eliminates protozoa, bacteria, and viruses. When traveling outside the country it’s usually necessary to purify.
3 main groups of pathogens that could be in your water source:
- Viruses: such as Hep A. Most North American water is free of viruses, but it’s still a good idea to treat for them. According to Mountaineering: The Freedom of the Hills, “Viruses are easily killed with chemical treatment but are too tiny to be removed by most filters. Boiling kills viruses.” (63).
- Bacteria: just a few of many include Salmonella or E-Coli which can be found in water in North America. Many filters can get rid of bacteria in the water, when used correctly.
- Parasites: such as Protozoa, tapeworms, flatworms and Cryptosporidium. Parasites are common in North America as well as other countries.
There are more than a few options for treating water. As always there are advantages and disadvantages to all of them. Here are some of the more popular options:
Filtering is very effective against large parasites and it’s effectiveness against bacteria varies depending on filter. There are many types of filters out there. Most filters work by pumping water through a filtering system, gravity fed or some are in-line filters that connect to your hydration bladders. Most filters are not effective against viruses, which is a bigger concern if you’re traveling out of country. Filters are often quick and the water taste is not altered but they do have some disadvantages. Glacial silt and other particles may clog or break the filter so it’s best not to solely rely on it.
Pumping filters: These filters can take a while to set-up but the main advantage of pumping is that you can move a lot of water through it. However, while pumping filters often times work great, they can be tiring, difficult to clean, slow and somewhat expensive.
Gravity fed filters: are lighter than pumps and usually easier to assemble. Because it uses gravity you will need to find something to hang the bladders from, which may not always be easy. Gravity fed filters are another great way to get a lot of water fast. A few disadvantages of gravity filters are that they are not always easy to clean and can be a bit heavy.
In-line filters: Some of the smallest of the filters are in-line filters. An example of three well know in-line filters include the Aqua Mira Frontier Pro, the Sawyer in-line filter and GeigerRig in-line filter. This is a quick way to filter water without much of a set-up. Disadvantages of the in-line filters are that they can be difficult or impossible to clean and because they filter from a hydration bladder they’re best for individual use.
The GeigerRig in-line filter, is what I’m most familiar with. This filter works on most hydration bladders, but when used on the GeigerRig the pressure pushes the water through the filter and it doesn’t need to be pumped or use gravity. The filter only weighs 2 oz. and is said to filter 99.9% of Giardia and Cryptosporidium. Besides being small it only costs around $28.00. The two main disadvantages of the GeigerRig in-line filter (that I found) was that if you’re using it for cooking it would take a while to squeeze water from the nozzle into the pan and you can not clean it.
Tablets, Chemicals and Purifying Options:
Chemical Disinfecting and tablets can be a lightweight and cheap option for cleaning your water. I’d recommend using a filter first to rid the water of larger particles.
Iodine-Iodine is inexpensive and very effective against most bacteria and viruses. Not effective against Cyclosporum. Because it most often comes in tablet form, it’s lightweight and compact. The disadvantages are that it takes 1 hour for cold or cloudy water and leaves a unpleasant taste. Also, if you’re allergic to iodine (like me) or if you have thyroid problems you can not use it.
Chlorine dioxide- Often in tablet form, same as Iodine, but it’s more effective towards all pathogens and has less health risks. The taste of the water is not altered significantly and it’s lightweight and compact. Chlorine dioxide takes around 15- to 30 minutes to work.
Chlorine- Chlorine is effective against bacteria and viruses. Not effective against Cryptosporidium or Cyclosporum (two types of parasites). Chlorine is light-weight and inexpensive but it will leave an unpleasant taste and takes a while to start working.
Ultraviolet Purification-Kills most all bacteria, viruses and protozoa. These devices are battery operated so be sure to bring extra batteries or a solar charger. The ultraviolet purification works very fast, but the water needs to be fairly clear for it to work.
Camelbak All Clear Water Purifier: Also runs on batteries and costs around $99. It’s said to kill all bacteria, viruses and protozoa but one disadvantage is that it weighs around 1 lb. It’s also a good idea to filter water of large particles before using this purifier.
Boiling- Boiling is the most effective method. Boiling is easy but not always convenient. The problem with boiling water is that it requires extra fuel which adds extra weight to your pack. It also does not remove large particles.
- When picking a source to draw water from, consider upstream contamination from farmlands, mining and civilization.
- Be sure to wash your hands or use waterless hand-sanitizer after using the bathroom and before handling food.
- Be aware of how you can accidentally cross-contaminate your clean and dirty water source.
- Dishes and your toothbrush should also be cleaned with filtered or purified water.
- Whatever you choose to use, a larger opening on a water bottle or hydration system will make it easier to fill-up at your water source.
Now it’s your turn: What process do you use? What’s the water source in your area like? What tips do you have for filling water from a dirty water source?
References: Mountaineering The Freedom of the Hills. 8th ed. Seattle: Ronald C. Eng and Julie Van Pelt, 2010. Print.