Use of GIS, Remote Sensing and AHP Techniques to Delineate Groundwater Potential Zones in the Nekor Basin, Central Rif of Morocco

Abstract

The scarcity of precipitation in the semi-arid regions due to climate change makes the assessment of groundwater potential zones (GWPZ) a very crucial process in order to mitigate the lack of potable water in the study area. Therefore, this study aims to combine multivariate techniques, Geographic Information System (GIS), Remote Sensing (RS) and Analytical Hierarchical Process (AHP) in order to delineate potential zones for groundwater storage in the Nekor Basin which covers an area of 905 Km2. Thence, the thematic layers, known of high importance in the demarcation of groundwater potential zones such as Elevation, Geology, Rainfall, Land Use/Land Cover, Drainage Density, Slope, Lineament Density, Curvature, Roughness, Topographic Wetness Index (TWI) and Topographic Position Index (TPI) were all used in the current study. Weights were assigned for all thematic layers using pairwise comparison as an AHP approach. The GIS-based analysis has revealed 15.56% and 63.95% of poor and moderate groundwater potential zones, respectively. Areas with good and very good groundwater potential were reported only in 20.48% of the basin. The results of the delineation study were validated with the hydrogeological map of the Nekor basin and the groundwater flow of six boreholes and one spring located all in the Ghiss-Nekor Aquifer. As a result, the comparison has shown a reasonable concordance with the groundwater potential zones classes obtained in the present study.