THE overthrow of Madagascar’s president in mid-March was partly caused by water problems—in South Korea.

urgent action is needed if we are to avoid a global water crisis.

Brazil and South Africa, which depend on hydroelectric power, have suffered repeated brownouts because there is not enough water to drive the turbines properly.

Does the world really face a global problem?

no one knows how much water people can safely use. It is certainly not 100% (the amount taken in Gulf states) because the rest of creation also has to live off the water. In many places the maximum may well be less than one fifth, the average for Asia as a whole. It depends on how water is returned to the system, how much is taken from underground aquifers, and so on.

An alarming number of the world’s great rivers no longer reach the sea.

Freshwater fish populations are in precipitous decline.