Suitable aquifers for MAR projects in the Emilia-Romagna Region according to current Directive and hydrogeological setting
Managed Aquifer Recharge (MAR) could be a crucial strategy for addressing the impacts of climate change. Specifically, infiltration ponds may help to replenish depleted aquifers, thereby mitigating the effects of drought or groundwater overexploitation. Additionally, it may contribute to reducing the risk of flooding by utilizing river waters. This research aims to identify water bodies (WBs, deriving from DQA “Direttiva Quadro acque”) suitable for MAR following Italian directives. The Emilia-Romagna Region's database includes 453 Surface Water Bodies (SWBs), such as rivers and other watercourses, along with 135 Groundwater Bodies (GWBs). An evaluation system to identify the optimal combinations between SWB and GWB to design infiltration ponds has been developed, focusing on alluvial fan systems along the Apennine foothills. First, GWBs were selected due to their poor quality and critical quantity issues, whereas SWBs were chosen based on their quality and ecological requirements (DM 100/2016). Forty-two combinations were identified between SWGs and GWBs. A quantitative and empirical evaluation was conducted involving a systematic combination assessment of key factors; each assigned a rating and weighting. The sum of these factors results in a global index for each combination of SWG and GWB. This allows for the establishment of a ranking for the WBs combinations, from the most to the least favorable. Key factors include river discharge rate, flood hazards, and the presence of non-active quarries near SWB. GWBs are evaluated considering lithology, permeability, and water table level. Our results enable to select all WBs suitable for MAR as permitted by Italian legislation and to rank SWB-GWB combinations specifically focused on infiltration pond MAR. Future research will focus on the best combinations identified in this study to characterize the optimal sites for implementing infiltration ponds MAR.