According to the OECD, if current trends do not change, 4 billion human beings will experience issues of “water stress” by 2030: North Africa, the Middle East, Central Asia and the U.S. Pacific seaboard are the main candidates.
The water stress index represents a combination of the allocation of natural resources (precipitation per capita) and intensity of use (usage per capita). This does not mean per se that we're going to die of thirst, but rather suggests a growing conflict between its usages. Economists use the term "trade-off": do either one thing or another. The alternatives are mutually exclusive, and something has to be sacrificed.
In the media debate, however, the terms of the issue are often misunderstood. In the dominant narrative, water scarcity is framed as a problem of physical scarcity. Water is becoming increasingly scarce, because we are squandering it by running out of “reserves,” and because humanity is growing, the world population having now exceeded 7 billion. Conflicts are therefore bound to arise over “blue gold,” the oil of the 21st century. The multinationals, long since aware of this, are trying to grab usage rights, to later be sold off at a profitably high price. Citizens have revolted against this attempt, proclaiming a “right to water,” acknowledged by a movement ranging from the UN to Pope Francis and now even codified in national constitutions. The same tendency equally forcefully vaunts citizens’ ownership of water (a trope of the “common good”), resulting in a corollary of requiring government management, alien to the logic of profit.
Such a reformulation has become so ingrained in the back of our minds that it has become a kind of conditioned reflex, an inalienable truth, even a mantra. All we need to understand the fundamental mistake being made is a little data analysis. Of course there is some truth in this, but the causal concatenation, the way concepts and data are juxtaposed, ends up somewhat blurry and ultimately misleading.