Potential sites determination of for boreholes implementation in basement zones (N'zi-Comoé region, Côte d'Ivoire): Contribution of a multi-criteria analysis and a Spatial Reference Hydrogeological Information System (SIHRS)

The high failure rate recorded during village water campaigns has led the authorities to mainly capture surface water for water supply in certain areas, as is the case in the south of the former N'zi-Comoé region (central-eastern Côte d'Ivoire). The objective of this study is to identify areas favorable to the installation of high-flow boreholes that can guarantee the supply of drinking water to the population over a long period. The slope, induced permeability, thickness, depth of the structure, fracturing density and drainage density constituted the database. Their processing and assembly thanks to a multi-criteria analysis made it possible to obtain a Spatial Reference Hydrogeological Information System (SIHRS). Thus, the identification of potential sites was made possible by the adoption of the weighted aggregation method for the cross-referencing of the selected criteria. The implementation of the SIHRS led to the map of potential groundwater sites. This map shows that only 63% of the study area has good groundwater reserves with good accessibility and easily exploitable that can lead to very good flows at the catchment structures. The SHIRS is a tool capable of facilitating decision-making in groundwater prospecting.