West Africa is subject to climatic variability with a long period of drought during the 1970s–1990s whose impact on groundwater remains poorly studied. This work focuses on the Kou basinin Burkina Faso, which holds a large groundwater resource resulting in exceptional springs. Thisresource shows signs of depletion that raise a critical question: What is the share of climate and thatof withdrawals in the depletion of the resource? To answer this question, we used a hydrogeologicalmodel calibrated in steady state and in transient regime (monthly time step 1995–2014; annual timestep 1961–2014). The results showed that pumping has a significant impact on the resource, especiallyin the vicinity of the pumping areas, and caused approximately 30% of the observed decrease inspring discharge. Drought periods and consecutive years without recharge also led to a decrease ingroundwater levels. Thus, precipitation deficits and variability, combined with increasing pumping,have endangered the resource.

Groundwater pumping Groundwater modelling Climate change Sudanian region Sedimentary aquifer