CE En 547 - Midterm Exam #2 KEY

Fall Semester 2017

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19. (gms) The objective of this exercise is the create a MODFLOW model of the Happy Valley site shown below. We will use a one-layer grid and assume uniform aquifer properties. The values for the sources/sinks will be given below.

Click here to download a zip archive containing a set of files associated with this project. Open the GMS project file named happy valley.gpr. Note that the project file references a background image that has been pre-registered. Use this as a base map to build your model.

Click here to download a copy of the solution.

Create and run a MODFLOW model using the conceptual model approach in GMS. As you build your model, consider the following data/instructions:

General Properties

Assume that recharge and K are constant:

Recharge: 0.0008 m/d

K: 15.0 m/d

For the top and bottom elevations, import the following scatter point data contained in the following two files that are included in the zip archive you downloaded:



Import these files as scatter point sets and use them to interpolate your top and bottom elevations.

Crystal Lake

Assume the following properties for the lake:

Sediment thickness (ave): 3 m

Sediment K (ave): 0.6 m/d

Stage: 287 m

Elk River

Assume the river bottom sediments have the following average characteristics:

width: 3 m

thickness: 2 m

K: 0.5 m/d

Use the following elevations:


Use the following pumping rates

Q (W1): -1000 m^3/d

Q (W2): -1500 m^3/d


Rotate your grid so that the major axis (x-axis) is aligned with the main river channel (roughly southwest to northeast). Use 90 cells in X and 60 cells in Y.


Build your model and make sure you have a reasonable looking solution. Your solution will be graded as follows:

a. Conceptual model and coverage setup/organization (2 pts)

b. Computational grid (dimensions, location, etc.) (2 pts)

c. Recharge and K (2 pts)

d. Grid elevations (top, bottom, starting head) (5 pts)

e. Representation of lake (6 pts)

f. Representation of river (8 pts)

g. Wells (3 pts)



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