Spatial variation of the water rising and water table salinity in the Basin of Ouargla (Algerian Sahara)

Abstract

The increase of waters requirements for both the needs of drinking water supply that the needs of industries and agriculture has pushed the services concerned of the hydraulics to develop a number of drilling capturing the aquifers of terminal complex (CT) and the continental intercalary (CI). This exploitation of groundwater has proved to be excessive which has created an imbalance of the water table and subsequently this situation has led and contributes in a direct way to the water table rising in Ouargla basin.The study shows that the problem of water rising has had serious effects on the physical degradation of soils by the congestion that it causes and the formation of gypseous crusts, compact, as well as the chemical degradation by the salinization of soils. The results of the study also show that the risk of salinity is proportional with the piezometric level of water table depth. The obtained values are too high and exceeds the authorized standards of water salinity, for instance the degree of water table salinity vary from: 2.4 g.l-1 and reaches 150 g.l-1 in some regions of Ouargla Basin.