A regional decline of groundwater level is observed in the El Khairat plain. The increase in extraction is probably the main cause. The evaluation of groundwater recharge is an important step for the sustainable management of groundwater resources. A conceptual ‘rainfall–runoff’ model is developed to assess the El Khairat aquifer recharge. The model calibration aimed to reproduce the measured surface runoff and the observed water table level. Only 17% of rainfall recharges the aquifer, and the rest is mostly lost to evaporation. Analysis of the groundwater-level hydrographs indicated different hydraulic responses of the aquifer following rainfall events. Upstream, the water table rise is fast with a large amplitude, whereas a dampened response is observed downstream.