The automatic delineation option for calculating landuse with in a drainage area that is in GEOPAK Drainage does not exist in InRoads S&S. It currently does not exist in SUDA either. I believe there are plans to have this type of functionality in a future release of SUDA.
communities.bentley.com/.../12600.subsurface-utility-engineering-sue-support-clips-technotes-faqs
communities.bentley.com/.../12600.subsurface-utility-engineering-sue-support-clips-technotes-faqs