Delta Life 7

28 DELTARES, MARCH 2017 iMOD unravels complex link between geology and groundwater flow Deltares has developed a new design tool: the SandBox. It gives people the chance to mould a design themselves. It contains a model of a section of the Dutch coast. Interventions in the rest of the world can be designed interactively in this way as well. Changes in the box are measured and transmitted to a hydraulic coastal model, after which the tidal flows and other model results are calculated and dis played immediately. The inno vative feature of the SandBox is the realtime link with a Delft3D Flexible Mesh model. That allows designers and stake holders to team up and produce a design, and communicate things like design requirements and the impact on the locality. You can also use the SandBox in education and science, and to inform people about flood risks. Designing with your hands Deltares SOFTWARE Groundwater levels sometimes reach anomalous levels, as in 2012 and 2013 in the Vispa basin of the Rhone Valley (Valais Canton, Switzerland). In close collaboration with the local authorities the municipality of Visp decided to investigate the underlying causes of this phenomenon. The subsurface geology was reconstructed in high 3D detail first in iMOD. The next step was to run a transient 3D groundwater flow model with local monitoring data. The iMOD model was used successfully to a) evaluate the effects of extraction from industrial and agricultural wells nearby, b) to simulate the interaction between surface waters (the Vispa and Rhone rivers) and the groundwater and c) to assess the effect of new underground infrastructures in and around Visp. Furthermore, the model allows stakeholders to assess optimal groundwater management options. Deltares will maintain collaboration with the Valais Canton in 2017 with a view to exten- ding the iMOD model to the entire higher area of the Rhone valley and transforming this into an interesting case study in an alpine environment. For more information: oss.deltares.nl/web/iMOD