The sediment plotter in HEC-RAS 6.0 and later reads the HDF results which can read large files (though very large files will degrade performance – so output increment management can still be helpful). But these recent versions of HEC-RAS still include legacy sediment results viewers for users who have built a work-flow comfort level with them. One of these legacy viewers read a binary output file which can get large, and like the O file (see previous section) will not plot if it grows larger than 2GB. There is no reason to write this file if you are not using the original sediment result viewers. (Then new sediment plotter has all of the functionality of the previous viewers and many new features, so HEC recommends transitioning to this tool.) Unless you are using these legacy viewers, this file is only taking up disk space and run time. This interface option allows users to choose whether to write it. New projects, created in version 6.0 or later do not write these files by default. So users have to check this box to use the legacy sediment output. But models created in earlier versions will write these files by default. By deselecting this feature, HEC-RAS will stop writing these files that are generally unnecessary.
