Linda Marsa chronicles the work of one Bob Derlet in the LA Times outdoor section this morning. Derlet has acted on the fleeting question of every backpacker who’s ever filtered or purified water from a pristine-looking mountain stream: “Is this really necessary?”

In short, Derlet’s research (which sounds like a lot of fun) finds that it’s not as necessary as people think. Although some disagree with Derlet, and the only way to be 100% sure that you won’t get some microscopic friends with your water is to filter or purify it, a surprising number of streams contain drinkably low levels of giardia and cryptosporidium. Knowing where the little buggers are most likely to be found can greatly reduce the chances of contracting the diseases associated with them.

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The article is very well written and a good read. I’m a little wary, however, of the suggestion that “good sanitary habits” means burying feces at least 10 feet away from water. I only hope that’s a typo and there should be another zero (or two) thrown in there.

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