ABSTRACT
This study covers the northern part of the Lake Chad basin, a 300,000 km2 area that is predominantly inhabited by pastoral livestock farmers. Competition for water is fierce in this arid area. The only surface water resource is Lake Chad and, therefore, most of the population depends on groundwater. Rapid population growth (2%/year) and the rise in sedentary lifestyles are increasing the demand for water. In addition, due to growing insecurity in the Lake Chad area, some communities have migrated further north, where there is no surface water resource. The Quaternary aquifer provides a tremendous opportunity for meeting this growing water demand, as it is shallow, extensive and highly productive. The ease of access to this resource makes it vulnerable to overexploitation in adverse conditions, such as the fall in precipitation predicted by some climate change models. To optimise investment for water supply, we have developed an atlas of this resource, based on the data collected on more than 1,000 recent boreholes. This atlas covers both the technical features of the resource and the production cost of groundwater. It is a decision-making tool that can be used to optimise investment in this very poor country.
