Filters and Purifiers

We stopped seven trekkers passing through Oregon to find out what they couldn't live without on their 2,550-mile journeys

If you want clean, safe water in the backcountry, this is the only purifier you should be buying

19 essentials designed to keep you alive

The outdoors can be deadly if you're unprepared. But these gear items will help you make it home alive—even if everything else goes wrong.

Kor’s slick Nava filter can process about 40 gallons, or 220 refills before requiring replacement

Of the dozens of poles, stoves, multitools, and other essentials we tested this year, we kept reaching for these six, from the Brunton Get-Back GPS, which stores up to three waypoints and steers you to the trailhead, to MSR SureLock TR-3s, which, at 20 ounces a pair, aren't ultralight, but they are quite sturdy and strong.

These six gadgets, from the AT&T Pantech Element, a waterproof, Android-based 8.3-inch tablet, to the Mophie Juice Pack Outdoor Edition, which doubles the battery life of your iPhone 4 or 4S, to the Steripen Freedom, a tiny water purifier, won't revolutionize your life on the road. But we promise they'll make it a lot easier.

What is the best method, gear, and brand for water purification in the backcountry. Would you recommend a water filter, a pump, or something like Steripen, or just water purification tablets or even a mixture of both? Nick Bangor, ME

I have been looking for a good minimalist water purifier. I have been looking at Katadyn Pocket water filter with Output Hose, but $ 320.00 seems dear. I just can't pull that trigger since usually I just boil water. But now I'm looking for more instant gratification nowadays—for under $120? FredSanta Monica, CA

Squeeze-bottle filters are handy for travelers and day hikers who don’t need to treat large volumes of water. Take one as a backup for a pump filter, or skip the pump if all you want is a bit of refreshment on the run. Be warned, though: Since bottle-style units rely…

The slow but steady First Need uses a three-stage matrix to draw out and starve viruses. Forcing water through the unit takes time and elbow grease on the pump handle, but the end product is virus-free and ready to quaff, with no need for additional chemical treatment. And because the…

The Miox is the first significant advance in backcountry water purification in years. Dip the unit into a pond to fill its thimble-size reservoir. A built-in table-salt compartment creates a brine solution, which the device—it’s slightly larger than a fat highlighting pen—then zaps with a small electrical charge. Dump the…

This 11-ounce filter’s reliability has made it a hugely popular option for nearly a decade. When it does eventually slow down, you just replace the pleated filter component ($30). You also get great volume per stroke; we filled a liter with just 43 pumps. A nifty zippered case includes a…

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Not only is this the fastest filter we’ve ever tested; it’s also the smallest. This hot-dog-size baby easily gushes out two Nalgenes per minute. Plus, the HyperFlow attaches to almost every water bottle, and you can clean it without tools. 7.4 oz; msrgear.com…

Portable Purification We’ve been big fans of Steripen’s UV-light wands for years. You just swish it around in your one-liter bottle for 90 seconds and it zaps everything from viruses like hepatitis to protozoa like giardia. This newest version is smaller, has a new optical water sensor that can sense…

Base camp essentials that take the rough out of roughing it

In the last few years I have really taken to trail running long distances. My long runs can last over eight hours and are often big loops or out-and-backs in the mountains. Stream water is abundant on the trails in Cascades where I run but unsafe to drink untreated. When I hike or backpack I can take my water purifier. While trail running I try and travel light. It looks like some of the treatment tablets take up to four hours and are not effective against all the nasties in the water. What do recommend for water treatment?—TomSeattle, WA

What's the best water filter for sub-zero temperatures? Chet Freeman Quincy, Massachusetts

I've had my MSR Sweetwater Microfilter for about four or five years now. I used it two or three times without incident right after I got it, but it has been in storage ever since. Now I would like to start using it again. Do I need to worry about mildew or bacteria in the filter and tubes? Is there an easy way to clean the entire apparatus? Eric Pittsburgh, PA

I'm planning a trip to South America this summer and want to invest in a water filter and/or purifier system. What do you recommend? Paul Salt Lake City, UT

Our group of four to six people takes a yearly fly-in fishing trip on a remote lake in northern Ontario. I'm in charge of water filtration. I have two MSR pump filters and still come up way short on water supply. Do you have any recommendations for a large group that can’t stand the taste of iodine? Ed Hburg, New York

1. BROOKS INFINITI JACKET The billboard-size logo on the back will make you feel like a pro during warm-ups, while reflective touches make it great for chilly dusk workouts. $100; brooksrunning.com The Goods: Road-Race Day 2. TRIGGER POINT PLANTAR FASCIITIS KIT The antidote to…

Have you tried the Aquira Frontier water filter yet? Also, what's the best way, that isn't too expensive or heavy, to treat water while backpacking? Claudia Asheville, North Carolina

I'm going on a trek through the Indian Himalayas near Darjeeling in early March, and don't know what, or how much, to bring. We’ll spend several days hiking between villages in moderately cool weather. What should I bring, and are iodine tablets sufficient to make the water safe? Chris Cincinnati, Ohio

I try to keep my backpack light, so for water purification (in Washington’s Cascade Mountains), I carry just a vial of household bleach and use two drops per quart of drinking water. I have never had any problems, but I have a cast iron stomach anyway. What do you think? Doug Tacoma, Washington

I planning to trek through Nepal and India and wondering what is the best purification and/or filter system to use. I have heard a lot about the SteriPEN. How does it compare to the rest? Miri Halifax, Canada

My sister is joining the Peace Corps and will likely be stationed in Central or South erica. I want to get her a water filter/purifier. What do you recommend? Julie California

I need a new water filter for summer trips into the Ouachita Mountains, and I'm torn between the MSR MiniWorks EX and the Katadyn Guide Pro. I know you're a fan of the MiniWorks, but I can't screw it onto my existing stock of Platypus water bottles. Is the MiniWorks superior to the Guide Pro? Greg Dallas, Texas

Planning to book that trip to Laos’s Houaphan province you saw in our Best Trips of 2007 feature? Don’t let a swig of tainted water ruin the journey. Steripen, which pioneered the use of ultraviolet light in portable water purifiers, has created the ultimate drinking companion for travelers. The…

This July, I’ll be doing a five-day, 50-mile hike on Oregon’s Pacific Crest Trail. I need to purchase a good water filter for the trip—one that’s very reliable in removing giardia and crypto, and durable enough to be used everyday by multiple people. Also, if I need water-purifying pills, it would be nice to have a filter that removes the iodine or chlorine taste. Is there such a beast? Henry ity, Oregon

I planning a year-long trip to Central and South America and seek your opinion on water purification. What is the best purifier or filter combo? We need super-durable, convenient, and compact. Landon Rifle, Colorado

Accessories

Do I need a pump or chemical purifier for a trip to the Boundary Waters next summer? On past trips I have used Polar Pure, but I know that you sing the praises of pump filters. Will I waste time pumping versus doing some fishing while waiting for chemicals to work? Help me decide, Oh Knowledgeable One! Brad Chapel Hill, North Carolina

Water Bottles/Hydration Systems/Accessories

Gear Wizard, what's the best backpacking water filter on the market these days? If reliability, ease of use, speed, and size trump price, what's the best? Josh Denver, Colorado

This theoretical question was inspired by the incredible courage of Aron Ralston. In his account of his ordeal, he mentions thinking that maybe he should save his urine for possible consumption when all his water had run out. My question, then: In the event of a life-threatening situation, could one use a water filter to filter the impurities out of one's urine, thereby rendering it fit to drink? I realize this is kind of a gross question, but the theoretical alternative (dying of thirst in the wilderness) is even grosser... Bill Charlottesville, Virginia

Is there such a thing as a battery-powered water-filtration system on the market? If you have ever spent long ounts of time and huge ounts of energy pumping water out of a lake or stre, you can see how carrying some small batteries to run such a system would be advantageous. Right now I use an MSR hand pump, which I just find is too labor-intensive. Carl Ellerslie, Georgia

I've been hearing a lot of talk about the best method of water purification: chemical (silver, iodine, chlorine dioxide) or filtration pumps. But isn't the least expensive and most effective way of purifying water simply to boil it for ten to fifteen minutes? Brice Rough and Ready, California

I've been backpacking several times borrowing other people's equipment, but now I'm getting ready for a trip in the Adirondacks and need to get some more gear of my own. Is it true that viruses are primarily a problem in the water in other countries? What viruses are potentially problematic in the U.S., and what illness do they cause? Adina Syracuse, New York

I have looked all over the Web for the SafeWater Anywhere filter, with no luck. Are they out of business or did they change their ne? If so does anybody make inline filters with a bladder reservoir (rather than bottles) compatible with a CelBak, for exple? I'm not interested in pump filters. F.G. Azz Minneapolis, Minnesota

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