I am trying to delineate watersheds in a region in order to do spatial interpolation by top-kriging at some ungaged sites. I have followed all the intermediary steps for the delineation (Filling, Flow Direction, Flow Accumulation, Pour Point Snapping) successfully. However, when I get to the Watershed tool, regardless of where I place the pour points, the output I get is the basin (generated with the Basin tool) in which the pour point is located. For example in the image attached, the output from the basin tool is shown on the left. When I run the watershed tool with the snapped pour point in red, the delineated watershed (in green, on the right) is just the basin in which the pour point is located instead of the upstream contributing catchment for that particular pour point.
Does anyone know what I might be doing wrong?
(I am using the Hydrology Tools in the Spatial Analyst Toolbox, ArcGIS 10.3)