A large part of humanity thinks that water comes from a tap. Part of the rest of humanity don't believe in taps, knowing that they are science fiction. They know that water comes from a bucket, hauled from the well, a couple of hundred meters away, if they are lucky, but more likely a couple of kilometers away. The third part of humanity know that water is to die for, literally.
Water wars are with us, though we don't really notice them. Water is a resource. Those who have it will seek to keep it to themselves and those who don't will fight and die for it. They have no choice. Aside from the small matter of drinking, it's also needed for growing food, sanitation, power generation and manufacturing.
Denial of water is one of the most cruel methods of waging war. Israel used it on the Palestinians. It's no coincidence that arid parts of the world are often the most violent. A warlord who controls the waterhole or the well, controls the area and the people who live around the water.
The UN gives a high priority to providing clean water. Unfortunately the global population is increasing rapidly, and there isn't enough water to go around. The technology for making sea water 'potable' (drinkable) is still in relative infancy and extremely expensive.
There's more to it than that. There are nations and people who believe that it is their right to grow lawns in the desert, or to shave or brush their teeth with the tap running and the plug open. These nations make news as their water resources dry up. There is also the problem of sea water swamping fresh water resources along the coast.
The water dystopia
As the population in Africa grows, and water becomes more precious, there is the distinct possibility of a spectacular blowout amongst countries along the Nile if treaties and international law fail. In parts of the USA, there is ongoing concern about availability of water as reservoirs are sucked dry to keep cities on the go. There is the possibility of internal water refugees there, and in other arid parts of the world. Interestingly legal conflict might arise between cities as blame is apportioned and resources are demanded. But what if it extended further into civil unrest if prolonged periods of drought and failing reservoirs led to water scarcity or failure of water supplies? And what if, like a number of countries on earth, your ability to drink depended on piecemeal purchases for household consumption?