Why Purify Your Water?
If you're camping in the backcountry, water purification is an important safety measure. Lots of little critters can live in mountain lakes and streams, like bacteria, protozoa, viruses, and flukes -- even those that look crystal-clear and "safe" can be contaminated. Purifying your water gets rid of these organisms, which can cause diarrhea, vomiting, fevers, and other kinds of illness which can ruin your trip.
Boiling Water Purification
The simplest way to purify your water is to bring it to a rolling boil for about a minute. This will kill any viruses, bacteria, and other microorganisms which may be lurking in your liquid, but will not remove dirt and sediment.
How to Best Purify Your Camp Water
The Center for Disease Control and Prevention suggests taking the following steps to make sure your water is safe and potable:
- Mechanical Filtration
- Chemical Treatment
- Let Stand for 15 Minutes to One Hour (depending on water temperature - colder water requires more time)
Mechanical filters are popular choices for backpackers, ranging in price from $35 to about $250. They have three basic parts -- a pump, an intake hose, and a filter, which may be made of ceramic material or activated charcoal. A basic mechanical filter will remove most everything that could be harmful except viruses, which require a special chemical insert inside the pump. In North America, however, viruses aren't generally found in backcountry water sources.
When selecting a mechanical filter, keep in mind its micron size, output, and pump force. The micron size should be 0.2 microns or smaller to ensure that microorganisms are removed. The output is measured in strokes per liter, meaning how many times you'll have to pump to filter one liter of water. Finally, the pump force refers to how hard it is to push the pump -- unless you've got a strong arm, beware of high numbers.
Disinfecting Camp Water
The most common and time-effective ways of purifying water chemically are with iodine and chlorine bleach, both of which will kill the most common pathogens present in natural fresh water sources. Iodine can be added to water as a solution, crystallized, or in tablet form. It generally requires 2 iodine tablets to purify 1 quart of water, and the process takes anywhere from fifteen minutes to an hour, depending upon the temperature of the water. You can also buy tablets to neutralize the taste and color of the iodine tablets.
In a pinch, chlorine bleach can also be used to purify drinking water. Add 2 drops of 4-6% hypochloride, soap-free bleach to 1 quart of water and let stand uncovered fifteen minutes to one hour, depending upon the water's temperature. Letting the water stand uncovered will help the smell and taste of chlorine to dissipate.
Water can also be disinfected with UV light, either with special devices specifically made for the purpose or by way of direct sunlight. To disinfect water with sunlight, collect it in a clear plastic bottle, shake it to oxygenate, and place in direct sunlight for six full hours. The combination of temperature and UV radiation will kill viruses, bacteria, and protozoa.
With the right preparation and equipment, your youth group's hiking expedition or overnight camping trip needn't be ruined by bad water. Simply take the proper precautions and everyone will come home healthy and well-hydrated.