Uncertainty estimation and evaluation of shallow aquifers' exploitability: The case study of the Adige valley aquifer (Italy)

Abstract

Evaluating the sustainability of water uses in shallow aquifers is fundamental for both environmental and socio-economic reasons. Groundwater models are the main tools to sustain informed management plans, yet simulation results are affected by both epistemic and parametric uncertainties. In this study, we aim at investigating the effect of model uncertainties on three assessment criteria: depth to water (DTW), recharge/discharge analysis and a newly defined sustainability index S. We consider, as a case study, the shallow aquifer of the Adige Valley, which is highly influenced by surface water dynamics, water withdrawals from pumping wells and a dense network of ditches. Both direct measurements and soft data are used to reduce uncertainty associated to the limited knowledge about the spatial distribution of the hydraulic parameters. Simulation results showed that the aquifer is chiefly influenced by the interaction with the Adige River and that the influence of anthropogenic activities on vulnerability of groundwater resources varies within the study area. This calls for differentiated approaches to water resources management. Uncertainty related to the three assessment criteria is chiefly controlled by uncertainty of the hydrogeological model, although it depends also on the strategy adopted for the management of water resources.