Bankfull Cross Sections
The Cross Sections Tool generates sets of cross sections perpendicular to the Centerline and Bankfull Centerline. These cross sections are used to calculate a number of metrics.
Steps
Inspect and manually edit errors in the Centerlines. The centerline should be generally smooth, run parallel with the sides of the channel, and stop just inside the extents of the survey.
Open CHaMP Toolbar/Topo Processing/Create Cross Sections
.
- Generate Cross Sections:
- Make sure the correct Survey Geodatabase is open.
- For Type, specify if you are processing the
wetted
orbankfull
centerline (you will need to repeat this process for both sets). - Click
Generate Cross Sections
. - The new set of cross sections will be added to the map.
- Classify Valid Cross Sections:
- Using the Select Features Tool, select any cross sections that:
- Do not span the channel (nearly) perpendicular to the centerline
- Cross several other cross sections
- Are exceptionally long (i.e. run parallel to the centerline due to a sharp bend in the channel)
- Run into a neighboring channel segment.
- Click
Classify Current Section as Invalid
- You may also re-classify a cross section as valid by selecting it with the Select Features Tool and click
Classify Current Selection as Valid
- You may also manually edit cross sections using the Editor Tool. Make sure all cross sections:
- start and stop on a wetted (or bankfull) extent.
- May Cross any Non-Qualifying island or bar.
- Do Not Cross any Qualifying Island.
- Represent a perpendicular sample of the stream channel.
- Using the Select Features Tool, select any cross sections that:
- Run this tool for both the
Wetted
andBankfull
Channels.
When you are satisfied that the Cross Sections are accurate, you may proceed to run your Final Validation checks on the data.
Troubleshooting
- This tool may take several minutes to run, especially for larger sites. Be patient and let the tool run to completion. Do not click ‘OK’ more than once while the tool runs.
- Selectable features are limited when this tool is active (panel is open). Click Exit Tool to return the selectable status to all available layers.