Multi-scale modelling for the understanding of flow systems in a layered aquifer, Urabá-Colombia

Numerical modelling is a valuable tool which allows the characterisation of groundwater flow behaviour, its interactions, and the representation of different flow systems that occur in an aquifer. A regional-scale model requires general information to describe the flow trends. In contrast, local and intermediate-scale models require a more detailed knowledge of the flow boundaries, and more field information. In order to understand the groundwater flow in the aquifer system of the Eje Bananero del Urabá Antioqueño-Colombia, a multi-scale numerical model was implemented using MODFLOW®. This was performed following modelling protocols on three spatial scales in which the regional model provided the boundary conditions for the intermediate pattern, and the intermediate pattern for the local model. Finally, we represented some details that relate local and intermediate flows to regional flows, in which surface-groundwater interactions involving both shallow and deep ascending flows became evident. The results obtained in this work show the potential of multi-scale modelling as a tool to recognise and understand the groundwater flows in a layered aquifer system, which provide grounds for decision-making and proper management of hydrogeological systems.