Assessement of the Physico-Chemical Quality of Groundwater in the Sidi Yahya Region, Gharb, Morocco

Abstract

Groundwater is the most important natural resource which cannot be optimally used and sustained unless its quality is properly assessed. The aim of this work is to study the physico-chemical quality of groundwater in the water table of the Sidi Yahya region (Gharb, Morocco). We have carried out a qualitative study of the water in different sites of the irrigated perimeter of Sidi Yahya. In fact several measurements (pH and groundwater depth) and laboratory analysis (ionic balance) were conducted to determine the physico-chemical characteristics of water. We prospected 33 wells distributed into 6 zones: A, B, C, D, E, and F. Data were statistically analyzed using the analysis of variance (ANOVA). The results showed that the depth of water table varied between 6 and 96 m and that 51.5% of the wells were highly to extremely saline, thus inadequate for irrigation. The studied zones do not have the same salinity level. In fact, the B and F zones represent a significantly higher salinity compared to other zones. Similarly, the difference was statistically significant between zones for pH, electrical conductivity, calcium, and nitrates. In conclusion, the use of waters of low quality for the irrigation leads to soil degradation by an accumulation of salts. This accumulation is more or less important depending on the quality of water, the nature of the soil, the climate and the technique of irrigation.