Water Wars: Myths and Realities (Part I)

To what degree are fears of geopolitical chaos over water scarcity justified?

August 15, 2007

To what degree are fears of geopolitical chaos over water scarcity justified?

What a difference a few years make. In the mid-1990s, Ismail Serageldin, then the World Bank's Vice President for Environmentally and Socially Sustainable Development, declared, "If the wars of this [20th] century were fought over oil, the wars of the next century will be fought over water."

In contrast, in the Brundtland Commission's seminal 1987 Report, Our Common Future, water use issues on a global scale were a relatively minor concern, warranting only one paragraph out of the report's nearly 400 pages.

How is it possible that something that should be obvious — looming scarcity of one of the most essential materials for human life — could arise so suddenly?

Partly, this increased anxiety over the prospect of "water wars" reflects our current ecological reality: Over the past century, global water use has risen steadily, driven upwards in roughly equal measures by population growth and economic development. But neither of these trends was unknown to people in the 1970s and 1980s.

Another part of the explanation for the current anxiety lies in our cultural environment. The prospect of "water wars" fits well with contemporary popular narratives. In water wars, we assume that we would see the brutal side of human nature emerging as we come face-to-face with scarcity.

The "Survivor" reality TV franchise provides a popular example of this kind of narrative, even if in that case both the scarcity and the conflict are engineered for viewers' presumed entertainment.

The prospect of "water wars" also fits with the view that global interconnections foster a "coming anarchy," arriving at our doors from other parts of the globe. The view that chaos is being brought home by the forces of globalization resonates with all sorts of contemporary anxieties, from terrorism to the global spread of diseases like SARS and on to the prospect of massive migration forced by environmental changes ("climate refugees").

So is a future of "water wars" all but inevitable, or is this nothing more than environmental scare-mongering? Just to pose the question in this way misses a third possibility — that we are already living in a world where access to water is determined, borrowing geographer Michael Watts' description of famine, by "silent violence."

While difficult to measure precisely, by most accounts, the world's water supply is well over a billion cubic kilometers. On the other hand, total surface freshwater — the water we can actually use — is estimated to be less than 100,000 cubic kilometers — a miniscule fraction of the world's total water supply.

But global water supply is not all that relevant, since water is a renewable resource. Water gets moved around and stored in various forms: Not just lakes and oceans, but also ice caps, clouds, underground aquifers and even in living beings (Star Trek fans may remember the description of humans as "ugly bags of mostly water").

The point is that it never disappears completely. Even the ratio of fresh to salt water is fairly stable. (Climate change has an impact on this, but rising sea levels — more salt water — may to some extent be counterbalanced by higher evaporation rates and thus more frequent precipitation).

The issue is: How quickly does it circulate — or how much of our accessible supply of fresh water is replenished over a given period of time?

In 1992, Sandra Postel, one of the first to warn of global water scarcity, estimated that the global "relatively stable source of supply" — rainfall onto land that does not run off in large floods — is about 14,000 cubic kilometers annually.

Estimates of total human water use, like estimates of water supply, vary quite a lot. Most estimates are somewhere in the vicinity of 5,000 cubic kilometers per year.

In other words, we are currently using about one-third of the water supplies effectively available to us. This might seem like a substantial cushion, but both population growth and economic development are continuing to cut into it.

With our global population projected to peak at 50% higher than its current level, and economic development a largely unquestioned imperative in rich as well as poor countries, water scarcity in the future looks like a greater possibility.

Looking at the global water picture, like looking at total volume rather than renewal rate, may also be a case of trying to measure the wrong thing. We need water at specific places and times.

And in most cases, our water is much more likely to be locally sourced than the vehicles we drive, the music we listen to and the food we eat.

This is true for a number of reasons. First, water is a fluid but dense substance. One cubic meter, or 1,000 liters, of water has a mass of one ton — so a substantial amount of energy is required to get it to do anything other than flow downhill.

Second, we require large amounts on a daily basis: About 50 liters — 50 kilograms — is a frequently cited figure for the daily per capita minimum required for basic drinking, cooking, cleaning and sanitation.

Third, in spite of its vital importance, its economic value in most uses is relatively low. Water values are often measured in mere cents per cubic meter.

Taken together, these make the transportation of large amounts of water across significant distances sensible only under exceptional circumstances. And "water wars," if they occur, are likely to be quite localized.

Editor’s Note: Read Part II of this feature here.