topic Re: Modifying a DEM in 3D Questions

Modifying a DEM

gen — Mon, 31 Jan 2022 03:30:09 GMT

Hi everyone! I'm new in using ArcGIS and I just want to know if there's a way for me to modify a DEM, like for example, I want to make a defined river deeper as if I'm dredging it. Is that possible and how? Thank you so much.

Re: Modifying a DEM

DanPatterson — Mon, 31 Jan 2022 04:27:28 GMT

"stream burning" lots of links on this.

ArcHydro has conditioning tools, but for a quick solution,

Take your river (polyline or polygon I presume).

convert it to raster with the exact same cell size, extent, snap raster as your dem.

assign where the river is a value equal to the depth you want to dredge (eg 1 meter, etc)

assign the non-river areas a value of 0.

take your dem and subtract the above ( eg Minus (Spatial Analyst)—ArcGIS Pro | Documentation or other approaches)

you now have a dem with a river whose is deeper.

I have assumed in the above that you dem extends under the river surface with elevation values...!

If not, then the process will be totally different

Re: Modifying a DEM

gen — Mon, 31 Jan 2022 05:13:22 GMT

Thank you so much, sir! Your response clarified a lot of things for me.