Spatial Assessment of Groundwater Potentiality Using GIS-Based Weighted Overlay Analysis: A Case Study of Leylan, Kirkuk, Iraq

• Aksm24028@uokirkuk.edu.iq dr_dalshad@uokirkuk.edu.iq

  Author

Groundwater resources in the Leylan sub-district of Kirkuk, Iraq, face severe stress due to overexploitation, random drilling, and mismanagement, necessitating urgent scientific strategies for sustainable water exploration. This study aims to delineate Groundwater Potential Zones (GWPZs) across the region (743.33 km²) by integrating Geographic Information Systems (GIS) and Remote Sensing (RS) utilizing the Weighted Overlay analysis. Ten diverse geo-environmental and hydrological conditioning factors were evaluated: annual precipitation, lithology, stream frequency, slope, geology, elevation, lineament density, drainage density, soil types, and Land Use/Land Cover (LULC). The thematic layers were standardized and assigned relative weights based on their hydrogeological significance. Spatial integration was executed utilizing the GIS Weighted Overlay tool, governed by the mathematical model of the Groundwater Potential Index (GWPI = ∑(Wi × Ri)

The resulting spatial model successfully categorized the study area into three distinct zones. Strategically, the High Potential Zone, which represents the prime target for well localization and Managed Aquifer Recharge (MAR), covers 180.69 km² (24.31% of the total area) and is characterized by highly permeable formations and optimal topographic depressions. The Moderate Potential Zone, acting as a vast regional aquifer reserve, encompasses the majority of the territory at 562.01 km² (75.61%). Conversely, the Low Potential Zone is highly restricted, occupying only 0.63 km² (0.09%) in isolated pockets. These findings provide a robust, data-driven framework to assist regional decision-makers in optimizing sustainable groundwater management and mitigating further hydrological depletion

• The Moderate Potential Zone: This zone covers a nearly whole size of the study area and carries a high proportion: 75.61% of study area of 562.01 km². It’s largely the terrain of the territory in most of the region and includes most of the plains, middle and transition areas in the region.

 • The High Potential Zone: It is a maximal area 180.69 km² and constitutes a large part of the drainage basin (24.31% of all the area in the total drainage basin). It is a long, topographic depressions and is distributed as the focal belts over the area and is composed of points like the ones at the belt, where the centre and southern parts intersect and the terrain features, where the topographic depressions meet

. • The Low Potential Zone: Only a small area of 0.63 km² (0.09%) is for which the region is found most effectively, as it is mostly confined in the very small pockets. Keywords: Groundwater Potential Zones (GWPZs)’Geographic Information Systems (GIS)’Remote Sensing (RS)’Multi-Criteria Decision Analysis (MCDA)’Managed Aquifer Recharge (MAR)’Spatial Modeling

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