Assessment of groundwater potential zones of Akure metropolis (Borehole data and VES data)

This research addresses recurring water scarcity during dry seasons in Akure metropolis, Nigeria—a crisis exacerbated by demographic growth, expanding domestic and industrial water demands, and groundwater overexploitation. Through comprehensive geophysical investigations, we developed a methodological framework to identify and spatially delineate groundwater resource prospect zones. Our approach integrated multiple hydrogeological parameters derived from electrical resistivity surveys (transverse resistance, hydraulic conductivity, and aquifer transmissivity) with lineament density analysis from satellite imagery to create thematic spatial representations. These parameters were systematically weighted using the analytical hierarchy process (AHP) within a multi-criteria decision analysis framework to construct a groundwater prediction mapping index (GWPMI).
The resulting groundwater potential prediction model (GWPPM) classified the investigated site into four specific categories: low, low-medium, medium, and medium-high potential zones. Validation against existing borehole yield data shows that nearly 92% within the metropolitan zones exhibits poor groundwater prospect, with only 8% demonstrating suitable characteristics for sustainable extraction. The reliability of our predictive model was confirmed through relative operating characteristic analysis, which demonstrated the predominance of low to medium groundwater yield capacity (100% correlation) across the study region. This research provides critical spatial intelligence for identifying viable groundwater development zones and offers a decision-support framework for sustainable groundwater resource management by local water authorities. The methodological approach presented here can be adapted for similar hydrogeological assessments in comparable geological settings.