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Watershed Dynamics
Streamflow STELLA Model: Troubleshooting Guide

The following describe solutions to problems that students may encounter as they use the streamflow STELLA model.

  1. Students cannot open the STELLA model:
    The demo STELLA program may only allow one model to be open at once. This may include any blank “New” model. To make sure that no models are already open, choose “Close” under the “File” menu, and close anything the program tells you is open. Then choose “Open” under the same menu, and select the Streamflow model file.
  2. Students’ screen doesn’t resemble the description in the activity:
    Students may have inadvertently opened the “Model Construction” layer or the “Equations” layer of the model. To return to the “Mapping” layer, find the small white box near the top of the left-hand grey margin. This box contains a triangle or two. Click on the upward-pointing triangle. The screen should change. If it still does not look correct, click on the upward-pointing triangle again. If there is no upward-pointing triangle, check to make sure that they have opened the Streamflow model.
  3. Students cannot move sliders to desired values:
    In the middle of the bottom of the slider box is a small box with a number inside it. Students can click on this number box and enter a value directly.
  4. The slider number box says “eqn. on”:
    Students may have accidentally clicked on the small button in the lower left-hand corner of the slider box (the button with the squiggle on it). Click on this button again and a number should reappear.
  5. Students have trouble entering streamflow predictions:
    Double click on the “Predicted Flow” icon, which looks like a tiny graph with a big colored border around it. Double clicking should bring up a bigger graph. To “draw” on this graph, click the mouse in the graph field in the location where you would like a line. Use the mouse to drag the line around. When you first open the Predicted Flow graph, this line is hidden behind the x-axis. Students may find it easier to click directly on the x-axis, then drag upward to make the line appear in the graph’s field. Drawing a graph takes some experimentation.
  6. Students cannot move between Page 1 and Page 2 of the “Results” graph:
    Students need to click on the yellow triangle in the bottom left corner of Page 1 of the graph.
  7. Students cannot clear the “Results” graph with the Dynamite tool:
    Students may have accidentally “locked” the graph, which prevents its being erased. Make sure that the icon in the lower left-hand corner of the graph is an opened lock, not a closed lock. If it is a closed lock, click once on the icon and it should revert to an open lock.
  8. Students cannot adjust the amount of rainfall:
    Double click on the “Rainfall” icon, which looks like a tiny graph with a big colored border around it. Double clicking should bring up a big graph. Students can adjust rainfall by clicking and dragging lines around in the graph field, but they may have an easier time using the table on the right-hand side of the screen. The “Input” column represents the day; the “Output” column represents the amount of rain on that day. Output (amount of rain) may be modified by clicking on the value you want to change and typing in a new value.