Question:

How do activate Site Modeler in InRoads SS3?

Answer:

The Site Modeler tools were not delivered in the SS3 version of InRoads.  Equivalent functionality can be found within the OpenRoads tools. 

http://communities.bentley.com/products/road___site_design/w/road_and_site_design__wiki/7021.openroads-support-clips-technotes-faqs