Dynamics of coastal aquifers. Conceptualization and steady-state calibration of multilayer aquifer system-Southern coast of Emilia Romagna

Worldwide, coastal aquifers have been heavily exploited by socio economic activities for several decades, and climate change and sea level rise have also been threatening coastal aquifers. The authorities and policymakers have been advised to find the solutions in order to achieve sustainable water resources management. The southern part of Po delta, Italy is a low-lying coastal area also experiencing tectonic activity. Along with low-lying topography, unstable shore line and sea level, the groundwater is heavily exploited by this deltaic multilayered system of aquifers. Hence, a multilayer three-dimensional model of this aquifer system has allowed for the investigation of the response of aquifer to natural and anthropogenic exploitation. The present work regards the conceptualization of the multilayer aquifer system using lithological cross-sections, surface water features, and appropriate boundary conditions and the steady-state flow modelling. The spatially distributed elevations of the groundwater table and piezometric head from the different aquifers have been calibrated. The values of model error statistics at a satisfactory range, such as R-squared, mean error, root-mean-squared error and model efficiency, confirm that the developed model is reliable, and calibration is obtained with good match between observed and simulated data. The developed model can be used as a decision-making tool for the authorities and policymakers in order to plan for sustainable water management.