Creating features for coastal "line source" watersheds?

Discussion created by scalos on Aug 17, 2010
I'm using ArcGIS 9.3.1 and ArcHydro Tools 9 to delineate watersheds in the Gulf of Alaska. 

I've delineated all watersheds that have a contributing drainage of over 1,000 sq. km, but I also need to delineate coastal "line source" watersheds that drain directly to the coast rather than into major streams/rivers.  It's easy to see these watersheds; they're right between coastal drainage points (where flow length = 0) as shown in this image.

Does anyone know how I can generate a feature class from these coastal line source watersheds?  Obviously, I could trace them by hand, but this would be super tedious.  I'm hoping to automate this process. 

I've attached a jpeg that shows the "line source" watersheds I want to delineate. 

Thanks for the help!