Bentley provides thousands of engineers with HEC software, documentation, and support for a variety of modeling tasks, from floodplain hydrology to river analysis to GIS integration. These important programs are all included in the HEC-Pack:
Graphical HEC-1 for flood hydrology calculations
HEC-HMS for hydrologic modeling
HEC-RAS for river analysis
HEC-GIS (aka HEC-GeoRAS) for data sharing between HEC-RAS and ArcInfo
Watch: HEC-Pack overview video clip