Numerical modelling of the Mulino Delle Vene Aquifer (Northern Italy) as a tool for predicting the hydrogeological system behavior under different recharge conditions

Abstract

Water scarcity periods will increase in frequency and magnitude in the near future, especially in Mediterranean regions, and proper groundwater management has been recognized as a key issue to mitigate possible impacts. In this context, numerical models acquire a special relevance to quantify the availability of water resources and predict their behavior under changing climate conditions. This work shows the procedure followed to model a mountainous fractured aquifer located in the northern Apennines (Italy) using an open source code. This aquifer feeds springs with an average discharge of about 96.8 L/s. Even though they are not exploited at the moment, these springs might represent a relevant resource of freshwater for public water supply and are essential for ecosystem sustainment. The main limitation faced to model the aquifer in a realistic way is the lack of data, which hinders the calibration of the model. A nonconventional procedure was followed to obtain information on the hydraulic parameters. The hydraulic conductivity is computed from a steady-state calibration for which a limited number of groundwater head observations are available, whilst information concerning the storage coefficient is obtained analytically from the spring discharge recession curve. Finally, the model is used for predicting the system behavior under different groundwater recharge scenarios. Numerical simulations and analytical approximations reveal that the studied aquifer can provide fresh water under different groundwater recharge conditions and has the capacity to smooth the effects of short drought periods, representing an option for water management strategies in the region.