MODFLOW-MODAEM Linkage

Users can link MODFLOW and MODAEM models. The main application of this linkage is for defining boundary conditions for a local scale model.  A regional model can be built with MODAEM and then linked to a local scale MODFLOW model. This is accomplished as follows:

1. Build and calibrate the regional scale model using MODAEM.
2. Build a conceptual model for the local scale MODFLOW model. When setting up the coverage properties for the source/sink coverages, be sure to toggle on the MODAEM Head and Observed Flow options in the Source/Sink/BC's list. If you have more than one MODAEM model in your project, you will also need to select which model should be linked to the MODFLOW model using the MODAEM models combo box at the bottom of the Coverage Setup dialog.
3. Mark the boundaries (or at least the upstream and downstream boundaries) of the MODFLOW conceptual model as MODAEM Head boundaries.

At this point, whenever the Map->MODFLOW command is executed, GMS will automatically launch the MODAEM model and calculate a head value for each grid cell coinciding with the MODAEM Head boundary. Furthermore, a flow value is computed for the boundary using MODAEM and assigned to the MODFLOW boundary as an observed head. This makes it possible to monitor the flow budget across the boundary to ensure that the changes made to the local scale model (insertion of remedial wells, etc.) do not violate the flow conditions inherited from the regional scale model.