When the word water appears in print these days, crisis is rarely far behind. Water, as is said, is the new oil: a resource long squandered, now growing expensive and soon to be overwhelmed by insatiable demands. Aquifers are falling, glaciers vanishing, reservoirs drying up and rivers no longer flowing to the sea. Climate change threatens to make the problems worse. Everyone must use less water if famine, pestilence and mass migration are not to sweep the gobe. As it is, wars are about to break out between countries squabbling over dams and rivers. The language is often overblown and the remedies are sometimes ill conceived, but the basic message is not wrong. Water is indeed scarce in many places, and will grow scarcer. Bringing supply and demand into equilibrium will be painful, and political disputes may increase in number and intensify in their capacity to cause trouble. To carry on with present practices would indeed be to invite disaster. ……