The surface of our planet is mainly water, yet usable water is in short supply. In some parts of Africa people have to walk several kilometres a day to get water, and they are the lucky ones. There, and in Asia, the prospect of conflicts over water is increasing. A particular example is the scheme to bring more water into Turkmenistan and its capital city, Ashgabat.

China has more dams than any other country, and many of them are in Sichuan, an earthquake-prone, mountainous region. The majority of them produce hydroelectricity. The region is well-placed to supply power to large industrial cities down the Yangtze valley, and when the dams were built this must have appeared a logical strategy. Now it looks foolhardy. Hundreds of Sichuan's dams have been damaged by the earthquake and could collapse during the coming monsoon season. (Editoria