Sawyer Water Filter

Sawyer Water Filter $60

www.sawyerfamilyprotection.com

3½ Stars

There’s plenty of water in the backcountry—ponds and streams and melting snowfields—but I’d sooner fetch a Krispy Kreme from a latrine than quench my thirst with wild, untreated water. That stuff is teeming with tiny critters looking to carve out a new life and raise a family in your lower GI tract.

I’ve tried water-filter pumps and purification tablets, but I don’t like the weight and bulk of the former and the funky taste of the latter.

Sawyer’s new Water Filter, a D-battery-sized unit that fits inside a quart Nalgene bottle, solved my problems. To use, simply fill the bottle from a water source, screw on the lid and suck through the filter’s attached straw. There are no parts to maintain, no taste, and no wait. A submicron hollow-fiber membrane borrowed from medical dialysis technology filters out 99.99999 percent of bacteria, including E. coli and salmonella, and 99.999 percent of protozoa, including giardia and cryptosporidium. The device delivers the highest level of filtration available in a portable water filter.

I used the filter extensively in the backcountry where marmots, pack horses and other beasts abound, and so far so good. I also liked the unit’s large, 32-ounce capacity, which holds nearly a third more than its competitors, so you can fill up less frequently or make it farther between watering holes. All of this is predicated on not pulling out and losing the bottle’s rubber drinking straw, a necessary component. I dropped mine several times and had to scour the talus on hands and knees to find it.

The filter treats 500 gallons and weighs 9.9 ounces with the bottle. For $60 Sawyer has a filter that you can splice into the flexible line to any bladder-style hydration system. A virus filter, recommended for third- world travel, is $120.

— Duane Raleigh