Can you please tell me how it will that help me delineating the water for the culverts?? ThanksThis will help you by checking your assumption that the watershed coming out of the processing is too big. Maybe its not.
I am trying to delineate subwatershed from a DEM. The results are quite wonky. I suspect that when it calculates the flow direction it is coming up with erroneous results. The flow direction grid looks weird.
I've tried using a variety of point data, even so much as turning my stream arcs into points and I am getting stripes, and areas that don't look anything like watersheds.
Are you following a process that includes filling in the sinks?
no, I didn't even know there was such a process.
I was wondering if I need to clip my DEM to my watershed area. Can it be too large?
What is the sink fill process? I just used the Spatial Analyst watershed tool. I think when it processes the DEM to get the flow direction there is some kind of problem.
You should burn the DEM with your river network too.
Regards