Water - Who's counting ?




© UNESCO / J.H.A. Kleijn (Kuwait, 1965) ; © UNESCO / Jean-Dominique Lajoux (Sahara, 1961) 

Click on the image to listen to the recording.


The International Hydrological Decade began on 1 January 1965. It was the first attempt to take stock of global resources of fresh water and to co-ordinate research across nations. 

In 1973, UNESCO radio devoted a report to hydrologic research. Two specialists of the Organization were interviewed. First of all, they defined hydrology as the science of international water resources and the science of hydrological cycles. The first question posed by this science was, how much fresh water exists in the world? The answer depends on hydrological phenomena related to planetary circulations of the atmosphere and oceans, and the distribution of land masses and seas. It also depends on human factors. Indeed, quantity is important for distribution, but chemical and bacteriological quality of water is fundamental. The expert concluded that policies must address the problem of water pollution, and the solution was to be found at a global level.

For this reason, the global distribution of water and its mobility predispose water sciences to international co-operation.

The questions and problems posed by this report are still relevant. The International Hydrological Decade was succeeded by the International Hydrological Programme (IHP), which has just published a report on global water availability, infrastructure and ecosystems: Here


Sarah Rigaudeau





Generous support for this project has been provided by the People of Japan


We have partnerships built upon a common vision and common goals