You can export AutoCAD Civil 3D pipe networks and their associated catchments to edit in Autodesk Storm and Sanitary Analysis.
Important: If a catchment is not associated with a pipe network structure, it cannot be imported into Storm and Sanitary Analysis. You can associate the catchment with a pipe network structure when creating the catchment or by editing the catchment properties.
Restriction: Ensure that pipes or structures you export to Storm and Sanitary Analysis are not named the same even if they are not in the same pipe network. AutoCAD Civil 3D allows a pipe and/or a structure to be named the same as a pipe and/or structure in a different pipe network. However, only one part that has the duplicate name can be imported into Storm and Sanitary Analysis, so parts from different networks may become connected to each other. To resolve this issue, use the Pipe Properties or Structure Properties to change the pipe or structure names before using the Edit in Storm and Sanitary Analysis command.
- Click Analyze tab
Design panel 
Edit in Storm and Sanitary Analysis. - Select the pipe networks that you have associated with the catchment data you want to export to Storm and Sanitary Analysis. Click OK.
- Create a new Storm and Sanitary Analysis project or select an existing project. Click OK.
The data is imported into Storm and Sanitary Analysis as follows:
- The AutoCAD Civil 3D drawing is automatically brought in as an underlay.
- Each catchment is represented by a Storm and Sanitary Analysis subbasin object. Subbasins are represented schematically in Storm and Sanitary Analysis. However, catchment objects appear in the drawing underlay.
- Pipes are represented by conveyance links in Storm and Sanitary Analysis.
- Structures are represented by the corresponding node element in Storm and Sanitary Analysis. For example, they may be junctions, inlets or outlets, or storage nodes.
- Inlets on grade are linked to outfall nodes with gutter bypass links. Inlets on grade require a bypass target for analysis. Those with either no bypass target, or a bypass target of OFFSITE will be imported with an Irregular Cross Section Conveyance Link connected to an Outfall with an element ID containing the prefix "Offsite-". The Outfalls will be drawn at an offset from the connecting inlet.