MODFLOW Case Study - Solver Problems with a Thin Aquifer

This exercise involves a variation of the Fremont River model. The following changes have been made to the original model:

1) Download and unzip the startfiles.zip file.

2) Save and run the model. Read the solution.

a) What do the red symbols mean?

b) Why did this happen?

3) Try fixing the problem by adjusting the starting heads to a larger value.

4) Try fixing the problem by adjusting the acceleration parameter and/or trying a different solver.

5) Try changing the starting head value to be just above the bottom elevation.

6) Change the starting heads to a constant value such as 400. Switch to MODFLOW-NWT and turn on the Newton solver.