Assessment of groundwater potential recharge areas using advanced decision models and spatial data: Applied to Sbeitla aquifer system, central Tunisia

Sbeitla is located in a semi-arid region, central western Tunisia, where groundwater is considered an essential resource for economic development and social well-being. The main objective of this study is the assessment of potential groundwater recharge and delineation of aquifer recharge. Structural and hydrostructural database coupled with remote sensing techniques (RST), was employed. The lateral variation of recharging zones was determined through ArcGIS software, utilizing TOPSIS approaches. Results reveal that the study area is classified in five classes, very low recharge (45%), low recharge (15%), moderate recharge (20%) and 15% of the plain have good to very good potential recharge. Predominantly located in the southern part of the Sbeitla region, these areas distribution is controlled by some natural features such as geology and geomorphology. The findings show that there are five places in the Sbeitla plain where water can soak into the ground. About 40% of the area doesn't have much water soaking in, while 15% has a little bit. Also, around 25% of the plain has medium amounts soaking in, and 20% has a lot. This tells us where water is going into the ground in Sbeitla, which helps us use it better. The potential recharge for the Sbeitla aquifer system, using TOPSIS and RST, is estimated to 13.5 Mm³/year. Although this recharging rate constitutes only 7% of the total rainfall, there is potential for improvement. TOPSIS and RST approach proves valuable for potential recharge areas mapping. This integrated approach underscores the significance of informed resource management in addressing water challenges in front to climate change. Thus, the combination of parametric methods and MCDM approaches such as TOPSIS, has shown its efficiency in decision for classifying aquifer recharge zones and will be an effective tool to assist researchers in this field.