Groundwater recharge study in arid region: An approach using GIS techniques and numerical modeling

To demonstrate the capabilities of Geographic Information System (GIS) techniques and numerical modeling for groundwater resources development in arid areas, specifically for the demarcation of suitable sites for the artificial recharge of groundwater aquifers, a study was carried out in the Maknassy basin, which is located in Central Tunisia. Thematic maps were prepared using a Hydrogeological Information System. All of the thematic layers were integrated using an ARCVIEW based model, enabling a map showing artificial recharge zones to be generated. Meanwhile, a ground water model, MODFLOW-2001, was used to estimate the effect of such water recharge on the piezometric behavior of the hydrological system. Additionally, these simulations helped manage ground water resources in the study area. The GIS-based demarcation of artificial zones developed in this study was based on logical conditions and reasoning, so that the same techniques, with appropriate modifications, could be adopted elsewhere, especially in similar aquifer systems in arid areas where the occurrence of groundwater is restricted and subject to a greater complexity. The efficiency of artificial recharge may be tested using hydrogeological modeling by simulating the effect of a potential groundwater refill.