Pumping and Climate Change Impact on the Continental Terminal Aquifer in the Cap Skirring Area (Southwestern of Senegal)

The Cap Skirring area is a touristic and agricultural area located on the Senegalese Atlantic coast having the sandy and clayey sandy Continental Terminal aquifer as the only available freshwater resource. This area has experienced major economic growth in recent years, associated with strong increase in population. As the area is located close to the coast, groundwater pumping is often problematic, accompanied by a significant decrease in recharge, and may induce saltwater intrusion and therefore a considerable increase in chloride concentrations in water. Within this scope, the herein study aiming to understand the impact of groundwater pumping and climate change impacts on the Continental Terminal aquifer in the Cap Skirring area was performed. Groundwater level fluctuations analysis between 1978 and 2019 showed a clear piezometric water level decline in the P2 piezometer. Chemical characterization showed, that the mineralization of the groundwater increases gradually from the center toward the flanks of the area. Predictive simulations carried out by hydrogeological modeling confirmed, that the combined effect of around 20% of pumping increase and recharge drop leads to a piezometric water level decline and that the largest declines are in the vicinity of intensively used boreholes.