[Kartographer]

The problem is this method does nothing for chemical contaminates, which are just as likely and can be just as deadly as most biological contaminates.

[djf]

True. But that’s kind of a choice people need to make based on simple intelligence and awareness.

I’m not going to collect water that flows out of a Dow treatment plant to drink. Or collect water near a cattle farm or place that might be contaminated with large amounts of agricultural runoff.

This method has one BIG advantage. It kills the pathogens that cause water borne diseases that can kill you literally in a day or two!

[5th MEB]

Unless you are getting your water downstream from a chemical waste dump or contaminated mine tailing's; the chances of you being able to drink enough naturally, chemically, contaminated water to cause you any harm as close to 0 as makes no difference. Now remember we are talking about fresh water, not salt or sea water here. All natural water is contaminated with chemical and mineral contaminants; it is the nature of the beast, water is the perfect solvent and over time it will dissolve any thing. The biologicals in water are the true danger to some one in the field and proper precautions should always be taken.