Delineation of groundwater potential zones in the Central Region of Ghana using GIS and fuzzy analytic hierarchy process

Groundwater is the preferred choice of drinking water for the most dispersed and rural communities in Ghana’s Central Region. Groundwater potential zone delineation has been identified as a vital step to help accelerate the achievement of Sustainable Development Goal Six (SDG 6) and contribute to the realization of sustainable water and land management. The central region is generally characterised by low success rate of drilling and water quality challenges particular along the coast. To characterize the groundwater potential zones of the region for drinking purposes, hydrogeological and hydrochemical data, coupled with Remote Sensing (RS) and Geographic Information Systems (GIS), were used. The weight of each theme (soil type/geology, rainfall, slope, land use/land cover, lineament density, etc.) was determined through the Fuzzy Analytic Hierarchy Process (FAHP) and overlaid in the ArcGIS 10.3 programme to generate the groundwater potential map of the region. The output map was classified into the following five groundwater potential zones: viz. very poor 0.03% (2.6 km2), poor 10.58% (1039.3 km2), moderate 11.78% (1157.4 km2), high 77.48% (7613.5 km2) and very high 0.13% (13.2 km2). The map provides a spatial distribution of the groundwater potential of the region to guide stakeholders involved in groundwater development and sustainable management of the resource in the provision of potable water for the coastal communities.