here is the message of a recent piece of research: we are extracting too much water from rivers, streams and lakes. The implication is significant: unless there is enough water in the world's rivers to maintain freshwater ecosystems, many economies would collapse, affecting over 1.4 billion people who live in river basins.

The study was conducted by the International Water Management Institute (iwmi), South Africa; the World Resources Institute, usa ; Center for Environmental Systems Research of Kassel University, Germany; and the World Conservation Union (iucn) , Switzerland. It demonstrates that a balanced water allocation policy is needed, one that provides sufficient water to the environment, as well as to humans. It is for the first time that researchers have assessed the impacts of water use on freshwater species. According to the 2003 iucn Red List of threatened species, 3,011 freshwater species are listed as threatened, endangered or extinct due to human activities.

Across the globe there are examples of over-exploitation. In both the Murray-Darling basin of Australia and the Huang Ho basin of China, more water is extracted than is available for human use