Department of Science and Technology of Water and Environmental Engineering, UFR of Earth Sciences and Mineral Resources, University of Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire
The Cotonou and agglomerations drinking water supply project is located in the District of Ouédo (commune of Abomey-Calavi). In this area, the water supply has become insufficient, due to urbanization and the deterioration of hydraulic infrastructure. An establishment of high-flow drilling by electrical surveys and brief particle study was thus undertaken. Five geological layers, whose resistivities and thicknesses varying respectively from 31.95 to 872.12 Ω.m and between 1.99 to 244.5 m are highlighted. Three aquifers lying between 60 and 114 m deep are revealed. These aquifers are formed of coarse elements with a diameter greater than one mm. A catchment field of sixteen boreholes, each providing a high flow rate (100-250 m3/h), was carried out. This one mobilized an overall flow of 2680 m3/h (i.e. 64,320 m3/d). This flow has contributed to the achievement of more than 60 % of the Millennium Development Goals development in terms of drinking water by Benin.