There is an old joke, made famous by the writer David Foster Wallace, in which one fish says to another, “How’s the water?” The second fish replies: “What the hell is water?”
That’s more or less the question Nature faced when putting together this collection of articles on the ubiquitous substance on which all life on Earth (not just that of fish) depends. Any attempt to cover the full spectrum of scientific and social issues associated with water is surely doomed to neglect something of importance. But Nature likes a challenge. This supplement is a compendium of intersecting stories that showcase how water affects the sustainability of healthy human civilization.
For millennia, the most primal concern about water has been having enough of it. Some argue that too much attention is paid to water supply, and that the real priority should be making do with what is available. Indeed, progress on conservation and efficiency has been impressive — the US economy now needs much less water per dollar of output than in previous decades.
But conservation can go only so far. Rivers, wells and artificial reservoirs provide ample supplies for much of the world, but arid regions still struggle. Some researchers in these water-starved regions are turning their attention to the wet sponge that is the planet’s atmosphere. New technologies could extract clean fresh water from thin air, and sharply reduce water scarcity.
No matter how abundant the supply, of course, water intended for drinking also needs to be clean and free of contaminants. Among the most pernicious are the ‘forever’ chemicals known as PFAS: chains of carbon and fluorine atoms held together by some of the strongest chemical bonds in nature, and impervious to most attempts to break them down. But engineers are devising various methods to crack them apart and purify PFAS-contaminated water.
Although water sustains life, it can also be a threat. Flooding can ravage communities. In a live webcast earlier this month, specialists shared their latest thinking about flood resilience. They painted an alarming picture of the way floods disproportionately affect the world’s poorest populations, even in rich countries, such as the United States. Indeed, 1.8 billion people (22% of world’s population) live in areas at risk of severe flooding — and almost 90% of them are in low- and middle-income countries. Some researchers say that much of the infrastructure put in place to tame waterways is proving inadequate, or even counterproductive. They advocate rethinking how water is handled in the built environment, including re-establishing the abandoned practices of ancient cultures.
The danger posed by water is of course increased by climate change. Minimizing its effects will require a large-scale push towards renewable power sources, but these tend to be intermittent, and therefore dependent on technologies to store and transport energy. One leading candidate for renewable power is hydrogen, which can be formed by electrolysing water. However, there is an inherent tension: an economy dependent on hydrogen energy will inevitably consume vast quantities of water. Reducing hydrogen’s water footprint is an important focus as renewable sources become a bigger part of the energy picture.
Finally, because of water’s central role in life, it is also a major component of many human conflicts. Wars have been fought over water access. Armies have wielded water as a weapon. But most commonly water is a casualty of war, as has been seen with the destruction of water infrastructure in the Russia–Ukraine war. Those who follow these events closely think that there is an urgent need to identify likely areas of water conflict, and promote greater collaboration between nations on water resources. We all need water to live — not just fish.
We are pleased to acknowledge the financial support of the FII Institute in producing this Outlook and the associated webcast. As always, Nature retains sole responsibility for all editorial content.
Source: Resources - nature.com