When you install Bentley SewerGEMS after you install AutoCAD, integration between the two is automatically configured.

If you install AutoCAD after you install Bentley SewerGEMS , you must manually integrate the two by selecting Start > All Programs > Bentley > Bentley SewerGEMS > Integrate Bentley SewerGEMS with AutoCAD-ArcGIS-Microstation. The integration utility runs automatically. You can then run Bentley SewerGEMS in AutoCAD mode.