  In the past years, water has become a global concern. This essential and
irreplaceable resource is unevenly distributed between Continents. North Africa
and Middle East Arabic countries appear to be the most menaced area. From a
starting point : 4.3% of the world population has access to only 0.67% of the
resources for sustainable soft water. After decades of voluntarism, self-help,
and of technical and development keen interest, times of worries have started.
Since the 50's, all the efforts, in the Arabic World, have tended towards the
mobilization of increasing volumes. The expected advantages of irrigated
agriculture and production of electricity have been lauded, as well as the
extension of distribution networks in cities and country side districts.
Today's big construction works contribute to legitimize present acting teams:
projects such as the Assouan high dam in Egypt, in its time the largest in the
world and the Syrian dam of Tabqa, the Moroccan slogan for a million irrigated
hectares. Under the triple shock of drought, pollution, and the tremendous
growth of needs engendered by population increase and urban growth, the natural
resource which we thought would be available for ever has become a scarce
economical good. The terms change fundamentally: scarcity, shortage, pollution,
confrontation are the key words of a new problematic time. Past certainties
fade away. We all have to ask ourselves the right questions and draw
conclusions. It might be better in this field not to adopt too sharp attitudes
and not to criticize systematically what used to be a short time ago the way to
progress.

Geophysics