Heading out into the back-country on a solo or group adventure is an exhilarating experience. Then there’s the bacteria, viruses, and parasites. Worrying about the purity of your drinking water is something hikers don’t have to do any more. Gone are the days when drinking foul-tasting, iodine-purified water was the only way to know the water was clean.
One of the most common water-borne illnesses is Giardiasis or beaver fever, which is caused a nasty intestinal parasite called Giardia lamblia. The majority of Giardia cases occur in third-world countries, however, the Center for Disease Control estimates more than 20,000 people are infected with Giardia in the U.S. every year. Cryptosporidiosis, indelibly called crypto, is another very common water-borne parasite. Fortunately, advanced filtration technology makes it possible to filter readily available surface water for large groups or a light solo trip. Portable personal filtration systems are great for emergencies, hiking, and international travel when bottled water isn’t available.
Water Purification Tablets
Liquid iodine and iodine tablets are one of the oldest water purification methods. Most sports stores and outdoor retailers sell a large packet of 25-50 iodine tablets for about $10. The cost to treat one quart of water is usually between .20 cents and .40 cents. Depending on the water quality, a second tablet may be required. Iodine tablets destroy bacteria and viruses including Giardia, however the common Cryptosporidium is not affected. Always follow package instructions carefully. Most brands take about 30 minutes to fully purify the water. Some companies also offer taste-neutralizing tablets that minimize the iodine flavor.
Chlorine Dioxide Tablets
To purify surface water collected from reservoirs, lakes, and rivers, municipal utility companies treat water with chlorine dioxide to effectively remove viruses, bacteria, and other pathogens. Several companies, including Potable Aqua and Katadyn’s Micropur, sell tablets that use the same ingredient. For less than .50 cents per treatment, chlorine dioxide tablets thoroughly remove all types of water-borne pathogens. Using chlorine dioxide, Giardia, bacteria, and viruses are killed in half an hour and cryptosporidium within four hours. Tablets are affordable, compact, highly-portable, and have a long shelf-life making them an idea choice for emergency kits, hikers, travelers, and adventurers.
UV Water Purifier
SteriPEN is the leading manufacturing of UV water purification devices. SteriPEN’s hand-held device and patented purification process sanitizes one quart of water in ninety seconds. Prices range from $70 for a compact Traveler model to $150 for a fully-loaded SteriPEN with solar-charging case. The SteriPEN is powered by four high-output AA batteries. Using fully-charged lithium ion batteries, the Traveler model can treat 100 quarts of water. While purchasing a battery-powered device for a backpacking trip might not seem like the best idea, adding an extra set of long-life lithium batteries or opting for the solar-powered model can greatly extend the operating time.
Gravity-fed Base-Camp Filters
Gravity-fed filters are an excellent choice for large hiking groups and filtering cooking water. Most systems cost between $70 and $100 and consist of a water bag and gravity fed filtration and tubing system. Katadyn’s Base Camp Water Filter costs $70 and holds more than two gallons of water. Water is filtered as it exits the bag through a tube and valve system. Depending on the water quality, 2.6 gallons can be filtered in about 20 minutes.
MSR sells a large capacity model called the AutoFlow Gravity Filter that runs between $80 and $100. The MSR AutoFlow holds four liters of water or a little more than one gallon. The efficient filter can purify four liters of water in less than three minutes. Hydration specialist Platypus has a lightly different approach with their CleanStream Gravity Filter System. The CleanStream uses two reservoirs to separate filtered and unfiltered water. Simply hang the unfiltered reservoir higher than the filter and watch the four liter bag fill-up with pure, filtered water. The CleanStream by Platypus uses an innovative hollow-fiber filter, however, it is not effective against viruses. Gravity fed filters are great for purifying large amounts of water and filling-up hydration packs.
Filters are generally effective at purifying 150-300 gallons of water, depending on the initial quality. Replacement filters for gravity fed systems retail for $40 to $50.
Portable Purification Systems
Katadyn Hiker PRO
The small and mighty Katadyn Hiker PRO uses the same high-capacity filter as the company’s Base Camp model. To improve filter life, Katadyn added a pre-filtration system in the hose inlet. The combination glass-fiber and carbon filter effectively removes giardia, salmonella, and cryptosporidium from 200 gallons of water. The Katadyn Hiker PRO retails $65 and replacement filters cost about $40. The Hiker PRO also includes a quick-connect adapter for filling hydration packs and water bottles.
Katadyn Filtering Water Bottles
Recreational filtration leader Katadyn offers a wide range of lightweight water bottles with integrated micro-filters and purification cartridges. Katadyn’s MyBottle filtration system includes a pleated glass-fiber filter with activated charcoal. Filtration can be improved by adding a supplemental iodine-impregnated ViruStat cartridge that destroys giardia, cryptosporidium, and other pathogens. Katadyn’s MicroBottle and EXstream purifiers use a similar modular cartridge system. Filtering water bottles retail for $30-$50 and replacement filters cost between $20 and $40. On average, water bottles can be filled over 100 times before the filter or cartridge needs to be replaced.
MSR MiniWorks EX Micro
The MSR MiniWorks is a compact, heavy-duty, high-efficiency water filter intended for rigorous use. The MSR Mini combines a ceramic filter element with carbon technology to destroy all types of pathogens, including giardia and cryptosporidium. The added carbon filter helps improve taste and remove chemical pollutants, chlorine, and iodine. To increase the filtering speed, the MSR MiniWorks includes an integrated AirSpring Accumulator that boosts output to one liter per minute. The MiniWorks filter can be attached directly to Nalgene water bottles or wide-mouth hydration packs. For ease of use in the back-country, the filter is designed to be used without tools. The MSR MiniWorks costs around $90 plus $40 for each replacement cartridge. MSR’s trademarked Marathon filters have long-life and 500 gallon filtration capacity making them perfect for backpackers and long-distance hiking.