Finally, field water disinfection has become lighter. Never did I notice the bulk and serious weight of water filter more than when I had to pack for a week in rural Haiti. In my Patagonia MLC pack I had just enough room for a Sawyer water filter bottle, a Cocoon travel sheet, and a stash of medical gear. Nothing else.
Here are two new purifiers that would have given me some spare room in my pack.
Traditional filters with 4 micron pores remove protozoa and bacteria, but tiny viruses are small enough to escape capture. Check out Katadyn's MyBottle, with 3-stage ViruStat purification technology including 0.3 micron microfilter, iodinated virus-toxic resin, and a carbon filter to remove bad taste. The best part? You get all this in a bike-cage-compatible water bottle.
In October, Sawyer’s already proven squeeze filter system will get upgrade to a 0.02 micron viral filter. And it will clock in at about 6 ounces—a boon for us weight weenies.
Of course, when all else fails, you can use what is typical for municipal water supplies worldwide: chlorine. Katadyn's MicroPur tablets are ultralight, ultracompact, inexpensive and provide total disinfection. These should be a staple in your backcountry/travel kit. You just need to plan for the extended time required for tablets to nuke microbes and deal with the icky taste. But, that’s better than the alternative.