tunisia problemas

Surface water resources in Tunisia are characterized by problems of quantity and quality. These resources are limited because of the semi-arid to arid climate found in most of the country, with episodic droughts, and a natural deterioration of water quality because of the salty types of rocks found within the country.

Tunisia receives on average 230 mm/year of rainfall; that is 36 billion cubic meters (bcm) of rainfall. However, this volume varies between 11bcm during a drought year and 90 bcm during a very wet year.

The variability of the climate under the Mediterranean influence in the north and under the Saharan influence in the south make rainfall at the same time scarce and unequally distributed in space and time. The annual precipitation is on average 594 mm in the north, 289 mm in the center and only about 150 mm in the south. The ratio between the highest observed values and the lowest observed values of precipitation vary from 4.4 in the north to 15.8 in the south,