HEC RAS Import Export File for Geospatial Data

HEC RAS has introduced 3D geometry for the description of river networks and cross sections.This capability makes it possible to import channel geometry of from CAD or GIS programs without conversion from real world coordinates to station elevation descriptions for the cross sections.Similarly water surface elevations calculated at cross sections can be exported to CAD and GIS where they can be used to create models surfaces for inundation mapping.
...........
Download this chapter
http://www.docstoc.com/docs/70195208/HEC-RAS-Importexport-files-for-geospatial-data