Working with a HEC-RAS Project

75 Articles

2D Conveyance Obstructions

Conveyance obstructions can be assigned to the 2D mesh to account for regions that are permanently blocked from conveying flow....

2D Flow Area Connection Issues

A flow area connection can be used to model a hydraulic structure between two adjacent storage areas, a storage area...

2D Ineffective Flow Areas

Ineffective flow areas can be assigned to the 2D mesh to account for regions where the water is not actively...

Adding a Base Map Layer

A base map layer provides high-quality background aerial and other imagery from different online map providers to add context to...

Adding an AutoCAD Drawing

This video details how to add and georeference an AutoCAD drawing file for a HEC‑RAS model. There are two ways of...

Adjust Elevations command

The Adjust Elevations command is used to set or adjust elevations for a portion of an existing elevation grid. The user...

Assign River Reaches command

The Assign River Reaches command enables the user to quickly assign a polyline as a river reach. Follow these steps...

Attribute Table command

GeoHECRAS allows the user to easily review and edit GIS attribute data using the Attribute Table command. The Attribute Table...

Common HEC‑RAS Workflows

GeoHECRAS can perform the following HEC‑RAS workflows: Floodplain Analysis and Mapping Floodplain Encroachment Studies Roadway Crossing (Bridge & Culvert) Design...

Crop Base Map command

The Crop Base Map command crops the base map (i.e., Google Map, Bing Map, etc.) to the elevation terrain data...

Defining HEC-RAS Storage Areas

Upstream and downstream boundaries of a river reach can be connected to a reservoir, lake, or other types of large...

Digitizing Elements

Digitizing (or drawing) elements on the Map View can be performed using the various HEC‑RAS specific commands (e.g., Draw River...

Draw Cross Sections command

Cross sections are located at intervals along a stream for characterizing flow carrying capability of the stream and the adjacent...

Draw River Reaches command

The Input | River Reaches | Draw River Reaches command enables the user to quickly draw a river reach on the Map View....

Generate Contours command

The Generate Contours command creates equally spaced contour lines from loaded elevation grid data. The user can specify major and...

Generate Terrain command

Digital terrain surfaces can be used for the following tasks: Extracting cross section geometry Computing 2D flow areas Determining bank...

HEC-RAS 2D Bridge Modeling

When working with bridges with complex geometry, modeling the hydraulics in 2D provides a clearer understanding and a more accurate...

HEC-RAS Bridge Modeling

HEC-RAS can be used to model roadway crossings, which can consist of single or multiple bridge openings and culverts. This...

HEC-RAS Flood Result Raster Grids

While GeoHECRAS constructs a flood map representing the area of inundation, it can simultaneously generate an elevation raster grid (or...

HEC-RAS Ineffective Flow Areas

Ineffective flow areas allow the user to define areas of the cross section that will contain water that are not actively being...

HEC-RAS Minor Loss Coefficients

Minor losses represent sources of energy depletion along a river reach that are not related to friction loss. For example,...

HEC‑RAS Conveyance Obstructions

Conveyance obstructions allow the user to define areas at a cross section that are permanently blocked from conveying flow. Conveyance obstructions...

HEC‑RAS Modeling Best Practices

The following best practices should be used when defining, analyzing, and reviewing a HEC‑RAS model: The model results should be...

HEC‑RAS Profile Plot Options

The HEC‑RAS profile plots can be customized for specific requirements, as described below. Cross Section Landmarks The defined cross sections...