Draw HEC-RAS Watermark

This routine reads an SDF output file from HEC-RAS. After flow analysis in HEC-RAS, run command File->Export GIS Data to save the water surface data. Below is the GIS Export dialog. Make sure to select the option "Water Surface Extents", otherwise the watermark data is not saved.

After loading the .SDF file, the program pops up a dialog for selecting the reaches and profiles that you would like to draw the watermark.

Shown next is an example HEC-RAS watermark plot based on a run of HEC-RAS using the file Hydrolesson.dwg, and using an input flow rate of 20,000 cfs, a Manning's n of 0.013 for the left and right bank conditions, and with the boundary condition set to critical depth:

You will note that the vertices of the drawn polylines for the left and right bank high watermark are exactly at the sections used to create the HEC-RAS input file, using the command Prepare HEC-RAS Input File. The more sections, the smoother the watermark polyline. You need to purchase a copy of HEC-RAS from the Corps of Engineers or other sources in order to use the input file and create the ".sdf" output to process in this routine.

Pulldown Menu Location: Watershed->HEC-RAS Water Surface Model
Keyboard Command: drawras
Prerequisite: Prepare HEC-RAS Input File, and the program, HEC-RAS or programs that duplicate the output of HEC-RAS