Working with Carlson Survey Files
Preparing the Alignment
This section is done by the Bureau of Right-of-Way.
Create a MicroStation drawing from the Carlson Survey data. Carlson has an option to save the file in AutoCAD dwg format. Save it as a version 2004 AutoCAD file since MicroStation v8 cannot open AutoCAD 2007 files.
Open the dwg file in MicroStation. Since Carlson doesn't use actual coordinates, you must position the alignment at the proper location. Attach other files as reference files to properly place the alignment. Once properly located, the alignment is copied into the ERL drawing.
Breaking up the Alignment
Make a copy of the ERL drawing. The name is not important because this drawing will be deleted once the process is complete.
Delete all features except the legacy alignments. Since MX cannot handle station equations or angle points, the alignment needs
to be broken at these points. Refer to a report of the alignment for equation
and angle point locations.
The easiest way to determine locations for the breaks is with the Station-Offset program. Start by attaching tag data to each alignment. Select the Attach Tag tool, then the alignment tag set and next, the alignment.
Enter the data for alignment label and start station. For this particular task, the alignment label is not significant. Select a cell that will be placed along the alignment to locate station equations and angle points. Use the Station-Offset program and select the Place Active Cell option. Key in the station values of the points where the alignment needs to be broken.
Use
the IntelliTrim tool 
to break the alignment. Select the Quick mode and Cut operation as
shown in the graphic. Select the first point at the origin of the cell placed in
the previous step and the second point somewhere nearby. This will cause a break
in the alignment. When transferred to MX, the lines will become separate
alignments.
Transfer Alignment to MX
Follow the steps outlined in Transferring MicroStation Alignments to MX to create the alignment in MX.
Use the RenameM add-in to rename the new alignment to conform to the MC_L naming convention
Transfer to MicroStation
Draw the alignments in MX using the NHAlign add-in and transfer to MicroStation. See Creating a MicroStation Alignment Drawing (v8) if you need information about this process.