I am attempting to create watersheds on random points along a river network.These watersheds should capture every pre-existing water catchment which is upstream of that point.
The Point Delineation Tool within the ArcHydro suite of tools is effective in generating watersheds encapsulating all of the area that drains to this point upstream.
However, when I try to use my departments pre-existing water catchment dataset as the 'catchment' feature in the Point Delineation Tool I run into trouble as there are no GridIDs assigned to this dataset.
I have tried to manually assign these values to the dataset but it is proving difficult to ensure that it all matches up with the other input datasets such as the Drainage Line dataset.
I was wondering if anybody might be able to advise a workaround for this problem?