Groundwater potential zone mapping using analytical hierarchy process (AHP) and GIS for Narshingdi District, Bangladesh

Abstract

Global groundwater resources face increasing pressure from overexploitation and climate change, while rising demand for drinking water, irrigation, and industrial use underscores the need for a systematic assessment of aquifer potential. Despite this urgency, agriculturally significant areas such as Narshingdi District, Bangladesh, remain underexplored, with limited data-driven evaluations to guide sustainable groundwater management. This study aims to delineate groundwater potential zones (GWPZ) in Narshingdi District, Bangladesh by employing a Multi-Criteria Decision Analysis (MCDA) framework integrating Geographic Information Systems (GIS) and the Analytical Hierarchy Process (AHP) to provide a systematic and data-driven assessment. Nine thematic layers, geology, land use and land cover (LULC), lineament density, drainage density, rainfall, soil properties, slope, roughness, and curvature, were considered and analyzed in this study. Weights for each layer were assigned using the AHP method, and a weighted overlay analysis within the GIS environment was applied to delineate the GWPZ maps. The resulting maps were validated against observed groundwater inventory points using the ROC curve, yielding an accuracy of 88.5%. The analysis classified the study area into five groundwater potential categories: very low (20.9%; 219.5 km²), low (1.2%; 12.5 km²), moderate (68.1%; 714.5 km²), high (9.4%; 98.4 km²), and very high (0.4%; 4.1 km²). The majority of the region falls under moderate potential, indicating a generally fair availability of groundwater, while areas of high and very high potential are limited, highlighting priority zones for sustainable management and development. Overall, the study provides a practical and systematic approach for delineating groundwater potential zones, offering valuable guidance for sustainable groundwater planning and management in the region.