I am using ArcGIS Desktop 10.4.
I have to calculate the upstream river catchments of all my small river catchments. As you can see in the picture below, there are catchments missing in a weird looking shape. Created with Arc Hydro tool "Adjoint Catchment Processing" after I created the catchments following the usual way from a DEM.
Do you have any idea why there are no adjoint catchments included at these white strips?
The white stripes seem to follow some, but not all, of the channel network. I add a picture of the stream network here below.
I don't really know the size of the river. It is a whole catchment, so the widths will vary a lot between the main stem and smaller tributaries. The polygons have a size of a few hundret sqm to maximum 2.5 sqkm. The DEM has a resolution of 25m*25m.
We are looking at the full catchment in the picture, its roughly 132km x 64km.