Numerical models for the quantification and management of groundwater fluxes in aquifers have been more and more frequently applied since the advent of computers and their continually increased computational capabilities. Nowadays, groundwater numerical models are pivotal tools to manage groundwater resources, and to forecast the possible impacts of management practices. The broad availability of graphical user interfaces allowed hydrogeologists and environmental engineers to implement complex numerical codes like MODFLOW 6, FEFLOW and HYDRUS. In fact, in the last decade groundwater flow models have been used to disentangle complex flow patterns with variable boundary conditions and subsequently to assess the fate and transport of contaminants in the subsurface. Nevertheless, flow and transport numerical models often require a large amount of data that also vary with the extent of the modelled domain (e.g., lab, plot, field or aquifer scale). Accordingly, this presentation shows different examples of groundwater flow and solutes transport models implemented at increasing spatial scales, where a mixture of field data collected on this purpose and data retrieved from open data repositories have been used to increase the robustness of both model input and output.
Key words: saturated unsaturated modelling, spatial scales, groundwater flow, remote sensing, solute transport.