Part 3 - Compute Deterministic Simulation
Now that a simulation has been defined, the linking of model alternatives has been completed for a simulation, and model alternatives have been imported into HEC-WAT, the user is now ready to compute the Russian River study.
1. From the HEC-WAT main window, from the Study Tree, extend Alternatives, extend WO, extend the Simulations folder and right-click WO-RR_Jan1997. From the shortcut menu point to Compute, hold down the Ctrl key, click Simulation.
2. The Compute Progress dialog box will open and the compute starts. The compute will Fail when it attempts to compute the HEC-FIA Real-time model.
Fix the Error in the HEC-RAS Model and Compute the HEC-FIA Model
First check to see if the Depth (Max).vrt file has been created at the specified directory. If it has, what differences do you see in the path identified in the error message and the path in your ‘runs’ directory?
1. In order to identify and fix the issue, close the Compute Progress dialog. From the Study Tree, right-click on the simulation and select Browse Run Folder from the shortcut menu.
2. Navigate to the WO_RR_Jan1997_RAS-Russian River Real-Time directory in the runs folder to see if the Depth (Max).vrt file was successfully created. You should see that the file was indeed created. So, why can’t HEC-FIA find the file? Take a close look at the directory name, you should see the issue is not that the file wasn’t created, but the path is too long, and the “e” is missing from the end of the directory name. This can be fixed by renaming the HEC-RAS plan.
3. Return to the HEC-WAT main window, from the Programs toolbar, click 
. The HEC-RAS main window will display.
4. Click Run | Unsteady Flow Analysis, or click 
from the toolbar. The Unsteady Flow Analysis dialog box will open. Check that the correct HEC-RAS plan Russian River Real-Time is being used. Click File | Rename Plan Title.
The HEC-RAS Edit Plan Title dialog opens.
5. From the HEC-RAS Edit Plan Title dialog enter “RR_Real-Time” in the Plan Title box and click OK.
6. In the HEC-RAS short plan Identifier keep the Short ID as “RT Unsteady” and click OK.
7. From the Unsteady Flow Analysis dialog box, click File | Save Plan.
8. Close the Unsteady Flow Analysis dialog (File menu | Exit), save the HEC-RAS project (File menu | Save Project) and close HEC-RAS (File menu | Exit).
Fix the HEC-WAT Simulation and Linking
Now that the HEC-RAS plan has been renamed the deterministic simulation must be updated and the model linking between HEC-FIA and HEC-RAS must be fixed.
1. From the HEC-WAT main window, click File | Save Study.
2. From the Study Tree, from the Simulations folder, right-click WO-RR_Jan1997. From the shortcut menu click Edit Simulation. The Simulation Editor opens.
3. From the Simulation Editor, from the Models table, select the new HEC-RAS model alternative name RR_Real-Time and click OK.
4. From the HEC-WAT taskbar click
to open the Model Linking Editor. The Model Linking Editor opens. From the Model to Link list select FIA-Real-Time.
5. Select all rows and click Default Model To Link. The Select Default Model To Link dialog box, select RAS-RR_Real-Time, and click OK. The Confirm Input From Model changing to window opens; click Yes.
6. Make sure the Grid From File locations are linked to the correct Location/Parameter (Parameter and Location/Parameter are the same). From the File menu, click Save. Close the Model Linking Editor.
Compute Modified Simulation from the HEC-RAS Model
Because the HEC-HMS and HEC-ResSim model alternatives were not modified, users can res-start the deterministic compute from the HEC-RAS model alternative. From the HEC-WAT main window, from the Study Tree, from the Simulations folder, right-click WO-RR_Jan1997. From the shortcut menu point to Compute, hold down the Ctrl key, click Simulation.
This time the compute should run through HEC-FIA without failing. Confirm the compute finished and close the Compute Progress dialog box.