Series: Purify Water on the Go
If you do not choose to filter the water before sanitizing it, the source of the water that you choose is extremely important. Look for clear water sources free of mud, contaminants, and visible signs of problems. A running water source is best.
Water far away from roads, fields, and other marks of civilization will contain the least amount of pathogens and chemicals.
Choosing the Right Sanitizer
When it comes to water sanitizers, there are a variety of options. In general, you can choose between UV filters, chlorine, and iodine. All of these sanitizers are effective at removing bacteria, but not all of them can remove viruses from the water.
UV filters only work well with pre-filtered water. UV filters are effective at killing pathogens from back country water. Most UV systems work by sanitizing and killing bacteria through focused UV lights, much like UV filters kill unwanted bacteria in homes and hospitals. SteriPEN®, produced by Hydro-Photon, Inc., is the most recognizable brand. They have several models — most battery operated — but the Sidewinder is especially interesting since it’s crank operated so no worries about those long expeditions.
Chlorine Tablets or Drops
Chlorine tablets or drops are effective at killing most bacteria present in water. If the water source is clear, there is less need for pre-filtering. Adding 16 drops of bleach or one tablet to a gallon of water will kill most of the bacteria in the water. Allow the mixture to stand for at least 30 minutes before drinking. If using tablets check the manufacture’s directions for treatment time. The problem with bleach is that it cannot remove chemical impurities from water.
Iodine Tablets or Drops
Iodine tablets are an inexpensive and lightweight method of water purification. Just like bleach, the mixture must sit at least 30 minutes before the water is safe to drink. Check the directions included with the tablets to be certain of treatment time. Iodine kills most organisms present in back country water. However, some protozoa are resistant to iodine, and iodine can often add an unpleasant taste to the water. Some tablets will be sold with a companion tablet which can be added after treatment to remove the Iodine taste. Follow the manufacture’s timing instructions to the letter as treating with the second tablet to soon can make the Iodine treatment in-effective.
The most old-fashioned form of water sanitation is boiling. Surprisingly, boiling water is one of the most effective sanitation methods. All pathogens will die through boiling, including viruses. The water must boil for at least a full minute at sea level — altitudes can affect this time though so boil for at least 3 minutes to be safe. Unfortunately, boiling water is extremely time consuming, requires fuel to bring the water to the necessary temperature, and a container capable of withstanding high heat. Boiling water usually works well at base camp, but can prove a big pain while on the trail.
Many adventurers decide not to worry about viruses, especially if in the USA, and focus mostly on filtration methods to knock out any bacterial or protozoa. But to be certain you’ve covered all the possible contaminants use a multi-step approach of filtration and sanitizers.
Next time, we’ll discuss filtering water in survival situations without the help of modern filters and sanitizers.
What techniques do you use for sanitizing water while camping?