How much to talk about this issue. I think a lot will happen before the water runs out but... I guess in underdeveloped countries it will run out first.
Only once I was on the verge of dehydration, I didn't realise what it was until I felt it, dizzy and about to pass out.
Water is very good here, even though they say you have to buy it. But in Argentina the water is scarce, there are no maintenance works, the water is cloudy with dirt and many other things. Especially because the governments use the good water for industry... the population doesn't matter at all.
It's really easy to take what we have for granted and to fail to see how difficult others have it. I feel grateful to have been born in an affluent country but just as easily have been born elsewhere in a country where the comforts I enjoy are not available; ample clean drinking water included.
I am very grateful at the moment. For example in Argentina we had to drill a borehole in order to have water, because otherwise there was not a drop, especially in the summer. And I know that nowadays the people there are having a very hard time. Problems with water and electricity.