Delineation of groundwater potential zones in Wadi Saida Watershed of NW-Algeria using remote sensing, geographic information system-based AHP techniques and geostatistical analysis

Sustainable management of groundwater resources has now become an obligation, especially in arid and semi-arid regions given the socio-economic importance of this resource. The optimization in zoning for groundwater exploitation helps in planning and managing groundwater supply works such as boreholes and wells in the catchment. The objective of this study is to use remote sensing and GIS-based Analytical Hierarchy Process (AHP) techniques to evaluate the groundwater potential of Wadi Saida Watershed. Spatial analysis such as geostatistics was also used to validate results and ensure more accuracy. Through the GIS tools and remote sensing technique, earth observation data were converted into thematic layers such as lineament density, geology, drainage density, slope, land use and rainfall, which were combined to delineate groundwater potential zones. Based on their respective impact on groundwater potential, the AHP approach was adopted to assign weights on multi-influencing factors. These results will enable decision-makers to optimize hydrogeological exploration in large-scale catchment areas and map areas. According to the results, the southern part of the Wadi Saida Watershed is characterized as a higher groundwater potential area, where 32% of the total surface area falls in the excellent and good class of groundwater potential. The validation process revealed a 71% agreement between the estimated and actual yield of the existing boreholes in the study area.