iMOD User Manual version 4.4 (html)

12.28SFR Surface water Flow Routing Package

The existing Surface Flow Routing package of MODFLOW2005 ((Prudic2004)) has been implemented in iMOD. With this package it is possible to route surface water through a network of segments. These segments are stored in an additional type of ISG file that contains more records than the conventional ISG. These additional records are specific for the SFR package and describe the connection and diversion between individual segments and how the water depth in the segments needs to be computed. The water depth is a function of precipitation, evaporation, external discharges and the computed hydraulic head. The cross-section of each segment can be specified by a rectangle, an eight-point cross-section and/or a relationship between discharge, width and depth. The SFR can discharge surface water in and from a lake as described by the LAK Package. The SFR is therefore a significant improvement in the interaction between surface- and groundwater.

There are a few limitations to the SFR package due to the iMOD implementation: