Wars For Water?

For years, experts and pundits have predicted that conflicts will increase over an ever scarcer and more valuable commodity: water. The fear has been that as populations grow and development spreads, vicious battles will erupt between water-rich and water-poor nations, particularly in major river basins where upstream nations control the flow of water to those downstream. To the doomsayers, global warming will only make those battles worse by decreasing rainfall and increasing evaporation in critical areas.

The argument has a certain logic. Consider the Colorado River, a major water source for seven U.S. states and part of northwestern Mexico. Even now the Colorado can barely meet the needs of the many millions who rely on it. If water levels drop, according to Peter Gleick of the Pacific Institute in Oakland, California, it "could derail the system altogether," igniting bruising fights over ever-diminishing supplies. Things could get even uglier over the Nile (shared by Egypt, Ethiopia, Sudan, Kenya and Uganda), the Jordan (shared by Syria, Lebanon, Israel and Jordan), the Tigris-Euphrates system (shared by Turkey, Syria and Iraq) and the Indus and Ganges-Brahmaputra systems (shared by India, Pakistan, Nepal, and Bangladesh).

Some of these rivers have almost sparked wars before: Egypt has repeatedly threatened military action if Kenya, Uganda or Ethiopia diverted the Nile, and Iraq, the last state in the Euphrates's journey, mobilized its troops against Syria in 1975 when Damascus cut off the tap.

It turns out, however, that such conflicts are not necessary or even likely. For one thing, many areas of the world are in for more, not less, precipitation in the years ahead. The Zambezi River in Mozambique has already flooded its banks twice in the past decade. More-northerly regions such as Canada, Scandinavia and Siberia should also expect a lot more rain. Already these areas are responding; Mozambique, for example, plans to build a hydropower dam on the Zambezi with Chinese financing, which could produce 2,000 megawatts of electricity for use at home and sale abroad. Coupled with the longer growing season expected up north as the weather warms, new irrigation projects should also lead to an increase in food production.

More to the point, increased rainfall could diminish tensions between certain states, making the risk of water wars lower than it's been in the past. For example, some long-term models show heavier precipitation in the highlands of Ethiopia and Central Africa, foretelling rising water levels in the Nile. And higher expected levels of rain in northern Europe could be used to mitigate the parching of the south.

Even in places that get less rain, conflict is not a given, since a number of drying regions are adapting to the change by building new dams and reservoirs or embarking on collaborative projects to make sure all those affected get the water they need. Take the Mekong. China controls the river's headwaters, and has worried the downstream states of Cambodia, Laos, Thailand, Burma and Vietnam by planning eight giant dams on the upper river, of which two are completed and two are under construction. Once finished, these dams will provide hydropower and irrigation for Yunnan, one of China's poorest regions. But they will also alter the Mekong's flow into the lower-basin states, interrupting the feeding and breeding patterns of valuable fish (including the endangered giant catfish) and depriving vital irrigation water to as many as 60 million people.