Load HEC-RAS 1D Geometry Layers

Use this tool to create ArcGIS feature classes from supported 1D geometry stored in a HEC-RAS geometry or plan HDF file.

Before you run it

• Select a g*.hdf or p*.hdf that contains 1D geometry.
• Prefer a plan HDF when the output must be clearly associated with a specific plan.
• Confirm the project coordinate system in HEC-RAS/RAS Mapper.
• Choose a writable file geodatabase for durable output.

Parameters

Parameter	Required	Behavior
Geometry or Plan HDF File	Yes	Reads supported geometry from a HEC-RAS g*.hdf or p*.hdf.
Override CRS	No	Used only when the tool cannot determine a projection from the project context. It does not reproject a detected CRS.
Geometry Elements to Load	Yes	Multi-select list. Defaults to Cross Sections and River Centerlines.
Output Cross Sections	Conditional	Enabled when cross sections are selected. Default is memory\CrossSections.
Output River Centerlines	Conditional	Enabled when river centerlines are selected.
Output Bank Lines	Conditional	Enabled when bank lines are selected.
Output Edge Lines	Conditional	Enabled when edge lines are selected.
Output 1D Structures	Conditional	Enabled when 1D structures are selected.
Output Geodatabase	No	Destination file geodatabase. With automatic creation, defaults beside the HDF as Project.pXX.gdb.
Create New Geodatabase	No	Enabled by default. Creates/reuses the named geodatabase and writes outputs to a plan feature dataset.

Procedure

1. Open Load HEC-RAS 1D Geometry Layers.
2. Select the geometry or plan HDF.
3. If the tool reports that the CRS cannot be determined, set Override CRS to the confirmed project coordinate system.
4. Select only the elements needed for the current review.
5. Keep Create New Geodatabase enabled for persistent output, or explicitly set each output.
6. Run the tool and review the geoprocessing messages.
7. Confirm the output location, coordinate system, feature count, and spatial alignment.

Outputs

Selection	Geometry	Feature class in organized output	Key fields
Cross Sections	Polyline	CrossSections	xs_id, River, Reach, RS, bank stations, reach lengths, StationElevation, ManningsN
River Centerlines	Polyline	RiverCenterlines	river_id, RiverName, ReachName, USType, DSType
Bank Lines	Polyline	BankLines	bank_id, BankSide, Length
Edge Lines	Polyline	EdgeLines	edge_id, EdgeType, Length
1D Structures	Polyline	Structures1D	struct_id, Type, River, Reach, RS, Description

StationElevation and ManningsN are text attributes in the GIS output. Use the source HEC-RAS model or the full RAS Commander APIs when complete arrays or editing workflows are required.

Interpretation notes

• The tool skips an element when its required HDF group/dataset is absent and reports a message.
• Structure support depends on geometry stored under the HEC-RAS Geometry/Structures HDF group.
• Output coordinates are assigned the detected/selected CRS; the tool does not transform source coordinates between CRSs.
• Geometry extraction is read-only. No HEC-RAS file is modified.

Common checks

• Compare cross-section stationing and reach association with the Geometry editor.
• Check bank/edge-line orientation and extent against the terrain and centerline.
• Confirm that structure count and river station values match the intended geometry.
• If the output is empty, inspect Troubleshooting.

See Outputs and naming for geodatabase conventions.