Originally Posted by wind_magic
I use different grades of water.
From "best" (most potable) to worst ...
How do you distill your own water?
As far as water from a stream, there is no way to know if it is contaminated. It doesn't take a farm upstream to do it. Ever hear of beaver fever? You can get it from the cleanest looking water. A simple backpacking water filter pump can eliminate this. In fact, you could filter water downstream from that cow farm too and very safely drink it. You test these things by putting food die in some water and it comes out clear on the other end.