Stephen Regenold updates the options in 2011:
In the woods, I use multiple water-purification products, from tablets to pumps. Product weight, speed of purification, and filtration type are criteria I assess to choose the right weapon against the bacteria, viruses and protozoa that may exist in a particular place.
Drop-and-dissolve tablets, including Potable Aqua iodine ($7, www.potableaqua.com) and Katadyn’s chlorine-dioxide Micropur product ($12.95, http://www.katadyn.com), are my most common defense. They are relatively inexpensive, light weight, and easy to use — just add a tablet into your water and let it fade away and do its stuff.
But tablets have a few limitations. You often have to wait 30 minutes or so for the chemicals to take effect. There is an aftertaste, too, especially with iodine. And for cryptosporidium, a nasty contaminant found in some areas, tablets will take four hours or more to neutralize, making them nearly unusable except for overnight application. …
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I’ve used Aqua Mira (the two bottle system) exclusively since 2003, and never had a problem. I’ll check out this Potable Aqua for a backup.
Water purification is a tricky one. There isn’t a perfect solution and with each method you have to compromise something – weight, speed, cost, effectiveness.
I tend to use iodine and a neutraliser when I have to purify as I find the pumps a bit bulky. Don’t think it takes out some of the particularly nasty bugs in some areas though.
Here in the Pyrenees I’m lucky enough not to have to treat the water – most streams are fine to drink straight out of in the higher mountains.
Phil
Water purification is a good topic.
* LIke Ray above, I use to use Aqua Mira exclusively; light is right.
* Last few backpack trips I used a Steri-Pen.
* For me, long runs are AM; backpack trips are the S-P.
* New products are out; there is more to learn about this.
* I actually drink straight out of streams 90% of the time (in NA; never in Asia).
* Can’t imagine why someone would use a pump – except they are by far the best for living/traveling – I used a Katadyn pump when I lived in Asia for 6 months. Buying bottled water in 3rd world countries is an ecological disaster; get yourself set up in advance and don’t do it!