I haven't read the whole of this thread, and this may have already been said earlier on, but I find that digging a gypsy well and allowing the ground to filter the water several times is a very effective means of achieving safe water.
I then filter it, boil it and if I'm really paranoid use silver purification tablets to make it safe.
I also look at local water life. If there is an abundance of fish and signs of local mammal life drinking the water frequently then I can assume that there isn't a high level of chemical pollution in the local water course.
If I do take water from a stream, then I almost always take it from the point at which it is fastest flowing, and again I filter it, boil it and add some sort of purification tablet or iodine drops.
Never had a problem yet.
Why take heavy bottles of water in your pack when we live in a land full of the wet stuff? If you take all the right precautions you should be able to live outdoors Evian free.
ATB
Josh H