Treating Water with Bleach

Will bleach make water safe to drink?

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I’ve read that household bleach—add four drops per liter of water and up to eight for questionable sources), then wait a half hour—can be used to purify water. Your thoughts?

Submitted by – Mario, Calabash, NC


Technically, we’re talking about water disinfection and not water purification, but otherwise, yes, household bleach will kill germs and make water safe to drink, generally speaking, if you follow your formula. Keep in mind that the pathogen cryptosporidium will probably be resistant to any halogen (in the case of bleach, chlorine). Also keep in mind that you’ll want to wait longer if the water is really cold, and you’ll want to strain the water if it has a lot of stuff floating around in it. —Buck