Determining the slope along a stream

[ChristineWehner]

I am looking to determine the slope along a stream in each cell in the raster. Does anyone know the best way to accomplish this?

[MarkBoucher]

1. You can get the slope of all cells in a raster using Spatial Analyst Tools.tbx\Surface\Slope.


2. If your stream layer exactly follows the stream you would get if defined by the raster (they don't always), you can create a raster from your stream layer (Conversion Tools.tbx\To Raster\Feature to Raster).


3. Then use the the Con() function to make another raster that only has the value from the slope raster where the stream raster exists (is not Null).

[ChristineWehner]

Thank you for your response.

I am trying to determine the slope along the stream in the downstream direction, creating a longitudinal profile. I believe that the slope raster does not necessarily give this value but calculates slope from the maximum change in z-value. Is there another way to ensure that the slope along the stream is being given in the downstream direction?

[TobiasOker]

Hi Christine,

I am trying to do exactly that. Basically after doing my DEM analysis (aka Terrain Reconditioning), I want to extract (and export to MS Excel) the x-y data for all the streams (drainage lines) I have generated for further slope analysis.

Could you please tell me how to extract and export the x-y data of the streams? Thanks.

Tobias

[DanPatterson_Retired]

No, but you can use the 3D analyst and create a profile along the stream and calculate slope from there

[TobiasOker]

Is it possible to extract the raw x-y data for all the streams and export to MS Excel?