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0 votes
by (180 points)

Hi - I would like to enter georeferenced cross section profile data from a topographic survey (data not in HEC-RAS format). I have created an 'xsSurface' layer extracted from a DTM using the 'Elevation' tool - I now want to update 'xsSurface' with my elevation values - however, the 'Update Elevations' tool allows you to enter elevation values only, but not the chainage/station value (my survey data is not at regular intervals across the CS, like those generated by the 'Elevation' tool).

How can I enter both the elevation and chainage values for each CS?

Look forward to your advice.


1 Answer

0 votes
by (3.8k points)
Hi Mike,

The Update Elevation tool finds both, station and elevation. Surveyed points are projected on their respective cross-sections lines. Stations are calculated as a distance of the projected point from its cross-sections starting point.
by (180 points)
Thanks for your reply. I uploaded a .csv file with x,y,z columns for each station - which I inputted into the Update Elevation tool to create a new 'bathymetry' layer which contained a column of elevation values which appeared as points on the correct XScutlines (the XsecID and Stations columns null values only). When I imported the subsequent .sdf file, the XSs had no elevation/station data attached (presumably because the .sdf file contained no xsSurface layer).

Alternatively, I imported a .csv with x,y,z data directly to HEC-RAS, which projected the XSs with correct station/elevation values. The downside of this is that it does not assign extra useful data that RiverGIS does (e.g. reach length, topology etc).

I'm sure the process is much simplier than it appears, but I am beginning to think it may be faster to manually copy and paste the z values(!)

I have the same problem than you, Have you achieved to use the Update Elevation Tool?
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