Combined Use of Multi-Criteria Analysis and GIS to Map Favorable Areas for High-Yield Boreholes Installation in the Tonpki Region (Côte d’Ivoire)

Located in the west of the Ivory Coast, the Tonkpi region with its estimated population of around 884,700 inhabitants faces many drinking water problems, especially in the dry season. The objective of this study is to identify sites favorable to the establishment of high-yield boreholes in this region by using GIS methods and multicriteria analysis. The combination of the different decision criteria after their weighting allowed the development of thematic maps (availability, accessibility and usability). These thematic maps were then combined to generate the summary map expressing the groundwater potential of the region. This map showed that the Tonkpi region has high groundwater potential (55%). These groundwater resources are unfortunately not all accessible, let alone exploitable as a whole. Consequently, high-yield boreholes can be installed in more than half (55%) of the area studied, in particular in the western part.