Unhelpful brusque comment. Of course water is a necessity.
Given a choice between a lot of the tap water across the world's cities and basically any strength of beer, I'd go for the beer if I had any doubts about local water quality. That tap water often requires boiling and/or filtration. Overly clever local water sellers often bottle the unfiltered tap water and sell it. I've had that experience as well.
Also true: Water purification is still a challenge even today. Plenty of cities don't even have drinkable water in people's residences.