Assessment of groundwater potential zones in an arid watershed using GIS and multi-criteria analysis: case of Khanguet Sidi Nadji, North-Eastern Algeria
Arid regions of Algeria face persistent water crises due to recurrent droughts and growing water demand, especially for drinking water and agriculture. This pressure have led to overexploitation of local aquifers. Accurately identifying potential groundwater recharge zones is therefore critical for sustaining aquifer replenishment and water security. In this study, we assess groundwater recharge potential zones in the Khanguet Sidi Nadji watershed in North-Eastern Algeria, employing a spatial multi-criteria decision-making (MCDM) methodology which is based on the AHP, that integrates remote sensing and Geographic Information Systems (GIS). The work methodology uses essential data from ten (10) factors, including lithology, rainfall, curve number, land use, lineament density, slope, drainage density, peak runoff, and soil hydrogeological group. Thematic maps /layers of each factor are produced using ArcGIS 10.8 and integrated using AHP to generate a composite groundwater recharge potential map. Results indicate that areas with high recharge potential comprise approximately one-third of the watershed, covering 27% of the area, moderate potential covers 41% and low potential covers 32%. We validated the final recharge potential map by comparing it with data from 55 high-yield wells distributed across the watershed. A strong correlation (r = 0.74) was found between high-potential zones and well locations. Overall, the findings of this study provide a powerful decision-making tool that contributes to the improved exploitation and protection of groundwater resources, thereby enhancing sustainable water resources management and assisting in addressing the growing challenges of water scarcity in the arid regions of Algeria.