Water shortage on a global scale is foreseen by forecasters from some of the world's leading corporate users of fresh water, 200 of the largest food, oil, water and chemical companies.

The consequences loom: Cholera may return to London, the mass migration of Africans could cause civil unrest in Europe and China's economy could crash by 2015 as the supply of fresh water becomes critical.

When the representatives of multinational corporations such as Shell, Coca-Cola and Procter & Gamble warn of the problem of scarcity of fresh water, it's time to listen up. These are not the dreaded ivory tower scientists eschewed by conservative Republicans, but representatives of the very corporations which put them in power and now run the country behind the scenes.

Shortage of fresh water is not a story for the mainstream media's headlines, but it is one I think we should be concerned about. It's no longer just a problem for the poorest people in the hinterlands; it will, in a few years, be a problem for us all.