Burn culverts into DEM

Question

Hello everyone,

I have seen several posts on burning across digital dams on a DEM (roads and the like). I have tried several of the proposed solutions to no avail. In the end I want to delineate a stream network using Fill>Flow Direction>Flow Accumulation without erroneous routes along roads. I don't have culvert database or anything so I created a shapefile and drew the lines across the digital dams. I created a field in the shapefile with an elevation attribute and entered the downstream elevation at the end of each line. I know I can convert this to a raster. I just need to figure out how to use these lines, in shapefile or raster form, to burn through the digital dams and have a final DEM that I can use for my stream network. I am using Arc Pro.

Thanks!

DeanDjokic · Answer

There are probably several ways to do that (specially since you are focusing on the change between two locations), but here is how you can take the points with Z and impose them into the DEM.  You will also need the new channel (2d) alignment that points "sit" on.

Use Arc Hydro tool “Construct 3D Lines from Point Values” (in Arc Hydro Tools Pro -> Watershed Processing -> Line Processing toolset) to create a 3D representation of your new channel.  Check tool help (for individual layer entry) to see the data schema requirements for the point and channel feature classes.  Do not provide optional "Input Raster".  Then use Arc Hydro tool “Convert 3D Line to Raster” (in Arc Hydro Tools Pro -> Watershed Processing -> Line Processing toolset) to create a raster from your 3D representation of the new channel from the step above.  Then mosaic that into the original DEM.  And now you have the "modified" DEM and you can do whatever else you want with it.

Again, if you are just trying to compare stream power and slope of the new channel to the original channel, this might be "too much" and you can just focus on the 3D vector representation of of the two sets of lines.

evrae003 · Answer

I have tried that one. I have the elevations that I want the final DEM to be where the lines are. It looks like that workflow gives me the lowest value from the DEM along the line and not the elevation I have in the shapefile for the line. When I originally tried that workflow it wouldn't generate the new raster but now it is. Also, I have gotten the DEM conditioning to work in Arc Hydro. So with these I can do my stream network as mentioned above now that I have burned through the digital dams. However, I have a new wrinkle that I forgot to ask about. I am looking at a restored stream where they cut a new channel that isn't on the DEM and I want to compare the slope and stream power of the new channel to the original channel because they made it much straighter. This requires me to burn the new stream elevations into the DEM which I have as a series of points. I'm not even sure where to start with this problem. Thanks!

danretired · Answer

You tried the solution to the right of your question too?

Solved: Arc Hydro DEM Culvert Burning - Esri Community