HydroCAD® Stormwater Modeling - Since 1986


File Compatibility

HydroCAD project files are always forward compatible.  This means that a newer version of HydroCAD can read any file that was created with any earlier version of the program.  As long as you have the latest version of HydroCAD, you will be able to open any project file created by any other HydroCAD user.  (For really old projects without an .hcp extension, you can still open the project by using Project/Import/HydroCAD-5.)

Example #1:  George creates a file using HydroCAD 6.0 and sends it to Bill.  Bill has HydroCAD 7.1, so he is able to read the 6.0 file without any problems.  Bill is able to read files from any version of HydroCAD up to 7.1.

Project files are sometimes backwards compatible.  This means that an older version of HydroCAD may not be able to read files created with a newer version.  This occurs because of the additional "vocabulary" that must be used in the data file to implement certain new features.  In general, files will be backwards compatible only if the person who creates the file avoids the use of newer features that are not present in the earlier version.

Example #2:  Bill creates a file with HydroCAD 7.1 that makes use of the new "weir rise" parameter.  George cannot open the file with HydroCAD 6.0 since his earlier version doesn't understand the new parameter.  Rather than ignoring the "weir rise" setting (which would produce inconsistent results), HydroCAD 6.0 refuses to open the file.  In order to read the file, George needs to update to the latest version of HydroCAD.

Note: George could manually edit the file to remove the "weir rise" parameter, which would allow his program to open the file.  However, his results are likely to be different than obtained by Bill, whose analysis may have been critically dependent on the "weir rise" parameter.  For this reason, we do not recommend the removal of any file elements.  If you cannot open a particular file, you should update to the latest HydroCAD release.

HydroCAD automatically saves to the earliest possible file format that is compatible with the current project.  This eliminates the need for a separate "Save as" command for backwards compatibility.  Whenever possible, this happens automatically.  If an older version is unable to read the file, it is because the project relies on newer features that the older program does not support.  The only solutions are to remove the unsupported feature in the newer program, or update the older program to the latest version.

Updating to the latest version is always the recommended solution.  This will allow you to read any HydroCAD project file created with any version.


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