La Houille Blanche
Number 2, Avril 2000
|Page(s)||12 - 28|
|Published online||01 July 2009|
Combien d'eau utilise-t-on et use-t-on ? Pour quoi faire ?
How much water do we use? For what uses?
Water uses are diversified but the use of this special "raw material" is not really taken into account in the economical statistics. The water quantities (3000 to 4000 billions cubic meters globally) vary between the countries and the uses: it depends upon the climate (if it is or not necessary to irrigate) and the level of development. In the world, the first use is irrigation (70%), followed by industry and thermal power plants cooling (22%) and drinking water for people (8%). But these percentages vary from one country to another. After a global increasing of the used quantities along the XX th century (multiplied by 6), we see important contrasts between the developed countries (low growth) and the others (high growth with enlarged irrigation). The ratio between the used quantities and the natural renewing resources, globally of 8%, varies from 1 to over 100% in some countries that exploit their water reserve). Moreover, the water used quantities generate waste water production (those of cities and industries have grown 20 times along the XX th century).
© Société Hydrotechnique de France, 2000