A geospatial decision-support framework for groundwater potential zonation and artificial recharge planning in the Bikkeru watershed, India

Abstract Groundwater, as a key natural resource held in aquifers, is important for the development of the economy, human health and ecological systems. With the increasing demand for water, it has become essential to extract groundwater. The development of geo-information technology has simplified the monitoring and management of these resources. This study presents a comprehensive methodology for identifying suitable artificial recharge locations in the Bikkeru Watershed, India, using geospatial tools and multi-criteria decision-making (MCDM) techniques, including the Analytic Hierarchy Process (AHP), Fuzzy-AHP, and Multi-Influencing Factor (MIF) methods. The novelty of this study lies in the comparative evaluation of AHP, Fuzzy-AHP, and MIF methods, followed by the selection of the best-performing model for identifying suitable artificial recharge sites. The framework took into account ten thematic layers: elevation, drainage density, land use and land cover, geology, rainfall, topographic wetness index, geomorphology, soil, distance from the river, and slope. Each layer had some weight assigned depending on how much it affects groundwater recharge potential. The research delineated groundwater potential zones (GWPZs), categorizing the region into high, moderate, and low recharge zones by the integration of these layers within a geospatial framework. Using ground truth data and the area under the curve (AUC) metric, the AHP model produced an accuracy of 73.4%, while the Fuzzy-AHP model achieved a higher accuracy of 87.5% and the MIF model achieved an accuracy of 70.2%. Lineaments and drainage networks were superimposed to identify artificial recharge site points. These points were then overlaid on the best-performing Fuzzy-AHP map to identify suitable artificial recharge sites according to the different groundwater potential zones. Furthermore, 186 possible sites for artificial recharge were found; suggestions to create check dams and percolation ponds would help to enhance groundwater replenishment. This study identifies and safeguards key groundwater recharge zones using integrated geospatial and decision-support methods, directly supporting sustainable development goal 6.