Water would be the most normal to drink while in the mountain area. Normaly you can drink the water directly from any swedish "fjäll" stream. Just dip you drinking cup in the water around you! If youare above settelments and the water is "moving" there should be no problem. If there is any second thoughts about if you can drink the wateror not you should boil it. If you cook the water it will reach 10 degrees and thus killing any bacteria in the water. Any polution in the water will of course not go away by boiling it, but then again polution is normaly not present in the fjälls. Right or wrong but I will consider the fish in the issue, trout, char and other mountain fishes has high demands on the quality of the water. So if these fishes can live and breed in these water it should be good enough for us to drink!