The Automate Transect feature in VO SWMM is a tool designed to streamline the process of assigning cross-sections to conduits in your stormwater modeling projects. This manual will provide you with a clear understanding of what this feature is and how to use it effectively.

The Automate Transect feature is located under the “Micro-Drainage” tab in VO SWMM. It simplifies the task of assigning cross-sections to conduits by automatically extracting cross-sectional shapes from a DEM file. This tool transforms the conduit shape into an “irregular” shape, which reflects the topography of the terrain, making your water modeling more precise and efficient.


Before utilizing the Automate Transect feature, ensure you have the following prerequisites in place:

  1. DEM File: You need a DEM file for the area of interest. This file contains elevation data that the tool will use to derive cross-sectional shapes.
  2. Conduits: You must have conduits within your stormwater network to which you intend to assign the extracted cross-sectional shapes.
  3. Cross-Section Lines: A layer in the form of a shapefile is required, containing cross-section lines that intersect the conduits. Each conduit should have precisely one cross-section line.

Using the Automate Transect Feature

Follow these steps to utilize the Automate Transect feature effectively:

1. Open VO SWMM: Launch VO SWMM and load your water modeling project.

2. Navigate to Micro-Drainage Tab: Click on the “Micro-Drainage” tab within VO SWMM’s interface.

3. Access Automate Transect: Locate and click on the “Automate Transect” option within the Micro-Drainage tab.

4. Configure Settings: In the Automate Transect tool dialog, configure the following settings:

  1. DEM File: Specify the DEM file containing elevation data.
  2. Cross-Section Lines: Choose the shapefile layer that includes the cross-section lines.
  3. Execute Automation: Click the “Start” button to initiate the automated cross-section assignment process. The tool will utilize the DEM data and assigned cross-section lines to modify conduit shapes accordingly.

5. Review and Verify: After completion, review the results to ensure that the cross-sectional shapes have been assigned accurately. Make any necessary adjustments if needed.