Although warnings that water crises, even water wars, are pending have a long history -- and a long history of being overblown -- there are increasing signs that the management of water resources worldwide is now reaching a tipping point. Many lakes and rivers are vanishing, and the quality of those that remain is deteriorating. Ground-water supplies are under pressure from overuse and pollution. Some fish populations are accumulating anthropogenic toxins; others threaten to disappear altogether (remember Atlantic cod?). Climate change may already be rearranging rainfall and glacial melting patterns, making life in arid areas increasingly untenable and intensifying floods in the already wet, and more populous, regions.
Water experts have long quipped that when the problem is not too much water, it is too little water, or water that is too dirty. Increasingly, however, the problem also seems to be that water is in the wrong hands. According to the Organization for Economic Cooperation and Development, nearly 70 percent of the water used worldwide goes to irrigation, rarely the most productive use for it. As economies and people shift toward cities and the demand for industrial and household water grows, the pressure on supplies is building. Some water must also be set aside for the environment, for instance, to maintain the ecosystems of river deltas. Meanwhile, nearly one billion people still lack access to minimally safe drinking water, and over 2.6 billion live without proper sanitation, a critical factor for children's survival.
Cracks are also showing in the world's water infrastructure. The massive inventory of dams, subsidized irrigation networks, and urban water and sewage systems built over the last half century is aging, poorly maintained, and underfunded. Cash-strapped governments and taxpayers are disinclined to pay the high costs of repairing or replacing these overstressed facilities, even while they expect them to continue to operate.