Mapping groundwater potential within the Owabi catchment with weighted overlay analysis to support climate smart agriculture in the Ashanti region of Ghana

Airborne magnetic and remote sensing datasets have been employed to delineate geological structures, which were integrated with other evidential layers in the Geographic Information Systems (GIS) environment to produce a groundwater prospectivity zones map of the Owabi catchment, in the Ashanti region of Ghana. The purpose is to help locate groundwater resources as an alternative to rainfall to promote Climate Smart Agriculture in the face of the challenges of climate change. Multi-index weighted overlay approach using multi-criteria decision-making process has been used to characterise groundwater prospectivity zones over the Owabi catchment area. Ten (10) evidential layers derived from remote sensing, airborne geophysical, hydrological, land use, topographical and geological datasets were classified, weighted, and integrated within the GIS environment. These were based on their relative contribution to groundwater accumulation to generate the groundwater prospectivity maps. The results showed that about 30% (134.8 km ² ) cover of the study area (449.3 km ² ) is a potential zone for locating groundwater, with a mean percentage favourability of 75%. These showed that the delineated geological structures are the major controlling factors in areas underlain by the granitoid. Therefore, the area has relatively high structural lineament density as well as high lineament intersection density with potential for groundwater for irrigation to promote Climate Smart Agriculture to mitigate the negative effects of climate change. This will further help achieve four (4) of the seventeen (17) United Nation’s Sustainable Development Goals (SDGs) 1 (no poverty), 2 (zero hunger), 6 (clean water and sanitation) and 13 (climate action).