Improved calibration of groundwater models using baseflow estimates for sub-catchments. Case-study: Upper Alzette, Luxembourg

Using MODFLOW the groundwater system of the Upper Alzette catchment was modelled. In general, calibration of groundwater models involves an inverse modelling strategy, using the measured groundwater heads in observation wells. An additional calibration strategy was employed considering the water balances of a number of subcatchments. Baseflow for each of the subcatchments was estimated and used as a criterion for an additional calibration. This analysis clearly showed that considering sub-water balances in the calibration process greatly improves the model results. The uncertainty of the model results was assessed, defining a spatially distributed ‘range’ for the simulated groundwater levels.status: publishe