To update an existing hydraulic model for exchange with WaterCAD, WaterGEMS, or HAMMER:

1. Select the Export to WaterCAD/GEMS/HAMMER tool from the Utilities menu or Utilities toolbar. The Export Wizard appears.
2. In the Model to create/update screen, make sure select Update an existing model option is selected.
3. Click on the button next to the File text field, to open the Select Model to Update dialog and the export file to update.
4. Click the Next button to move to the Source Options screen.
5. In the Source Options screen, specify what source option to use: Use Fence, Use Selection Set, or Use View (the default option - None - will export all features from the Master DGN).
6. Click the Next button to move to the Target Scenario screen.
7. In the Target Scenario screen, make sure the Update selected scenario option is selected as well as the scenario that should be updated (default: Base).
8. Click the Next button to move to the Update settings screen.
9. In the Update settings screen, ensure that the appropriate check boxes are enabled for Add, Remove, and Update of elements in the hydraulic model.
10. Click the Next button to move to the Finish operations screen.
11. In the Finish operation screen, make sure the Would you like to build a model now-option is set to Yes.
12. Click the Finish button to start updating the hydraulic model.

    The MicroStation Message Center will provide feedback on the export process.

13. Once completed, the updated hydraulic model can be opened in WaterCAD, WaterGEMS, or HAMMER.