By Hydrosimulatics INC  

If possible, read "Effect of Topography on Regional Flow Systems" (pg. 195) in Groundwater, by Freeze and Cherry.

The graphics below show the flow nets for two vertical cross-sections that are identical in depth and lateral extent. In both cases there is a major valley running perpendicular to the page at the left hand side of the system, and an upland plateau to the right. In the top graphic the upland water table configuration, which is assumed to closely follow the topography, has a uniform gentle incline such as one might find on a lascustine plain. The bottom graphic, on the other hand, has a hilly upland water table configuration such as one might find in glacial terrain.


  • Develop a model that can be used to simulate the flow system in a sloping terrain shown in the top graphic above using the MAGNET modeling platform.
  • Develop a model that can be used to simulate the flow system in a hummocky terrain shown in Figure 6.3b on page 196 using the MAGNET modeling platform.
  • Comment on the effect of topography on the flow systems.
  • Compare your model to that presented under the Education video library: Regional Vertical Circulation
  • Comment on the importance in understanding such complex flow patterns (particularly with respect to the locations of recharge areas and discharge areas) for aquifer protection, siting of waste disposal facilities, and managing/inventorying groundwater dependent ecosystems.

MAGNET/Modeling Hints:

  • Use ‘Synthetic mode’ in MAGNET to create a model domain.
  • To create a 2D vertical profile model in Synthetic mode, use a line feature and the 'Equal to Y (e.g., Water Table)' option to delineate the water table surface toward the top of the model domain. 
  • After your initial simulation, you can "clean up" the display by then making the space above the water table inactive with a zone feature ( 'Flow Properties' tab > 'Zone Type' > 'Inactive' ).
  • Use a relatively large NX (e.g., 100) to resolve the water table shape.