I have been drinking a lot of tonic water because my legs are giving me grief again and also a lot of iced lemon tea. I am fortunate enough to have lived on a private, untreated water supply most of my life, so I can drink most water. Where we are now, we drink untreated, unfiltered rain water. I have been for the last 2 years. When I lived in the UK, the water we drank was either straight off the mountainside or was from a deep well. I can only think of 2 occasions where the water has either not been drinkable or has failed for some reason - once when we lived in the Lake District in England when hikers broke the pipe from our tank leading into the farmhouse and another whilst we were on tour in Macedonia... the tap water in the hotel was cloudy and it wasn't a water pressure issue. We needed water so it was the one and only time we actually had to use our water filter and UV Steri-light pen (the combination cleared up the water and killed any viruses left unfiltered (too small for the filter) rendering the water safe and fit to drink).