In the 2010 product version, the .stm file was changed from earlier versions. However, previous versions of the .stm file (2009 and earlier) can be imported into Autodesk Civil 3D with the import command.
When importing .stm files from previous versions, they can contain Hydraulic Grade Line (HGL) values but will not contain some of the other hydraulic properties.
The following pipe values are calculated in Storm Sewers but are not found in older versions of the .stm file (before 2010):
The following structure values are calculated in Storm Sewers but are not found in older versions of the .stm file (before 2010):
To obtain these missing values, open the older version of the .stm file with the 2010 version of Storm Sewers. Then run the calculation again and save.
The .stm file will then contain the values listed previously and will display them in Autodesk Civil 3D after using the import .stm file command.