Impacts of climate change and pumping on groundwater resources in the Kou River basin, Burkina Faso

• Published in: Comptes rendus. Geoscience Vol. 355; no. S1; pp. 439 - 464
• Main Authors: Tirogo, Justine, Jost, Anne, Biaou, Angelbert, Koussoubé, Youssouf, Ribstein, Pierre, Dakouré, Denis
• Format: Journal Article
• Language: English
• Published: Paris Académie des Sciences. Institut de France 01.01.2023; Académie des sciences (Paris); Académie des sciences
• Subjects: Agricultural production; Aquifers; Climate change; Drinking water; Drought; Environmental impact; Environmental Sciences; Geology; Groundwater; Groundwater levels; Groundwater modelling; Groundwater pumping; Hydrogeology; Hydrology; Land use; Rain; River basins; Runoff; Sciences of the Universe; Sedimentary aquifer; Sudanian region; Water resources; Water springs; West Africa
• ISSN: 1778-7025; 1631-0713; 1778-7025
• DOI: 10.5802/crgeos.207

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 basin in Burkina Faso, which holds a large groundwater resource resulting in exceptional springs. This resource shows signs of depletion that raise a critical question: What is the share of climate and that of withdrawals in the depletion of the resource? To answer this question, we used a hydrogeological model calibrated in steady state and in transient regime (monthly time step 1995–2014; annual time step 1961–2014). The results showed that pumping has a significant impact on the resource, especially in the vicinity of the pumping areas, and caused approximately 30% of the observed decrease in spring discharge. Drought periods and consecutive years without recharge also led to a decrease in groundwater levels. Thus, precipitation deficits and variability, combined with increasing pumping, have endangered the resource.