The HYDRUS-1D and MODFLOW software packages were coupled to produce a groundwater model of the Nete catchment (northern Belgium) that would improve simulations of near-surface hydrological processes, including temporal and spatial variabilities in groundwater recharge rates. The present paper reports the practical implementation of the HYDRUS package for MODFLOW. Several issues are discussed: the choice and design of MODFLOW zones for coupling to one-dimensional HYDRUS profiles; time discretization of the MODFLOW and HYDRUS components, numerical oscillations and related warm-up periods; and the presence of seepage water in zones of shallow groundwater. In this study we delineated MODFLOW zones on the basis of groundwater depths as obtained with a calibrated steady-state version of the model. Transient simulations are then compared with observed groundwater depths derived from a piezometer network. We summarize a number of priorities and issues that need to be addressed in order to improve the model and achieve sound coupling of the two parts at the catchment scale, while keeping computation times reasonable.
|Title of host publication||Proceedings of the 4th International Conference HYDRUS Software Applications to Subsurface Flow and Contaminant Transport Problems|
|Place of Publication||Prague, Czech Republic|
|State||Published - Mar 2013|
|Event||Hydrus Software Applications to Subsurface Flow and Contaminant Transport Problems - Czech University of Life Sciences, Faculty of Agrobiology, Food and Natural Resources, and PC Progress, Ltd, Prague|
Duration: 18 Mar 2013 → 22 Mar 2013
|Conference||Hydrus Software Applications to Subsurface Flow and Contaminant Transport Problems|
|Period||2013-03-18 → 2013-03-22|