Create drainage analysis surface from USGS data in Infraworks and import to Civil 3D

Last updated: 2026-02-06

If you have not downloaded data yet, please refer to Download elevation data for drainage/visualization surface

Create InfraWorks project and add data

1. InfraWorks > New...
   1. Set the coordinate system on creation. It will look like HARN/WI.CountyWI-F
2. Verify view style is Conceptual View and not Engineering View in upper right corner.
3. Manage tab > Content Panel > Data Sources
   1. Add file data source > Raster Data
      1. Add DEM file(s). All intended files should be selected at the same time. InfraWorks will merge them into a single surface.
      2. Right-click Raster_DEM_Tiles > Configure
         1. Verify Type: Terrain
         2. If dataset is not Lidar-Derived Tiled DEM, assign coordinate system
4. Set home view: Upper right corner > down arrow > Set Current View as Home
5. Optional - Add imagery
   1.  Add file data source > Raster Data
      1. Add imagery file(s). If multiple are selected, IWX will merge them into a single surface
      2. Right-click LaCrosse_WROC_2020 > Configure to assign coordinate system
         1. Geo Location tab - WROC MrSIDs will be Wisconsin Transverse Mercator (WTM)
         2. Raster tab > Classification: Aerial, Clip to Model Extent
6. Export IMX file - Present/Share tab > Share panel > Export IMX
   1. Select only the area needed for hydro analysis. The smaller the file, the easier it will be for Civil 3D to process
7. Create a new file in Civil 3D to hold the surface
8. Create a surface in Civil 3D from IMX - InfraWorks tab > Import panel > Import IMX