Finding uphill or downhill areas along a road

Question

Hi everyone,
I need to determine uphill or downhill areas along a road section in a raster map. I know MapCal program can only do this for 100x100 pixels. But my study area (1500x1500 pixels) is too big to run this program. I was wondering if there is way to do this in ArcGIS.

Thanks in advance.

-Mike

MikeTotti · Answer

If you have a digital elevation model of your area and the spatial analyst extension for ArcMap then you can use spatial analyst to determine slope. Then you can reclassify the slope raster to highlight areas within a given slope range which is your uphill and downhill areas depending on which way your traveling on the road. You could also create a buffer polygon along your road to clip out only the area under the road that your interested in.

Hope this helps,

Tyler

Hmm Ok I got the point. Thank you, Tyler, for your help.

TylerBoyle · Answer

If you have a digital elevation model of your area and the spatial analyst extension for ArcMap then you can use spatial analyst to determine slope. Then you can reclassify the slope raster to highlight areas within a given slope range which is your uphill and downhill areas depending on which way your traveling on the road. You could also create a buffer polygon along your road to clip out only the area under the road that your interested in.

Hope this helps,

Tyler