topic Re: DEM BURNING in Water Resources Questions

DEM BURNING

ErnestDankwah — Wed, 19 Feb 2014 18:44:29 GMT

I need help burning my roads data into my 3m resolution DEM to generate watershed. Any help? I have a roads dataset which I have already converted to raster with the same resolution as the DEM.

I need to roads to burn into the DEM with the output being a new DEM so that I can use this to delineate watershed for road culverts. Can anybody please help? Thanks.

Re: DEM BURNING

MarkBoucher — Wed, 19 Feb 2014 21:41:09 GMT

I need help burning my roads data into my 3m resolution DEM to generate watershed. Any help? I have a roads dataset which I have already converted to raster with the same resolution as the DEM.

I need to roads to burn into the DEM with the output being a new DEM so that I can use this to delineate watershed for road culverts. Can anybody please help? Thanks.

Why do you want to burn the roads in? In terms that I'm familiar with, burning lowers the grid cells in the DEM.

Re: DEM BURNING

ErnestDankwah — Wed, 19 Feb 2014 22:22:39 GMT

Mark, I am trying to raise the roads. Since roads are barriers to flow, I am trying to raise it from the surrounding ground. I would want
merged my roads with the DEMs so the road locations would have 3m more of elevation so that I will use this newly created DEM to
generate watershed using road culverts as the pour points. I would want to know the catchment for each road culverts(s).

Thanks.

Re: DEM BURNING

MarkBoucher — Fri, 21 Feb 2014 20:40:28 GMT

You can use the "build walls" tool. Use the road polygons as the "innerwalls" with a buffer of 1 (makes 2 cell thick wall). The height of the wall can be very large (1000'). Then you need the "agreestream" layer to include the culvert crossings for the "breach" layer. If you have pipes in the parallel to roads, you may need to be creative. One option is the make your DEM grid even finer (smaller cells) somehow. This will give you more refinement horizontally, but the elevations in the DEM should be the same vertically. With the finer DEM grid the agreestream and innerwalls layers won't "conflict" as much when they are parallel.