To go to the next step, add some purifying solution such as Katadyn Micropur Tablets ($14 for 30). They’re basically chlorine tablets that kill viruses, bacteria, and parasites.

Katadyn's MicroPur tablets are ultralight, ultracompact, inexpensive and provide total disinfection. These should be a staple in your backcountry/travel kit.

Katadyn’s Micropur tablets are a great (and economical) option for purifying a wide variety of water sources. The kit includes 30 tablets, which are as easy to use as plopping into your water to ...