Susquehanna National Heritage Area Act This bill establishes the Susquehanna National Heritage Area in Pennsylvania, which shall include Lancaster and York counties. The Susquehanna Heritage Corporation is designated as the local coordinating entity for the area. The bill prohibits the corporation from using federal funds for the acquisition of real property or any interest in real property. The corporation shall prepare and submit a management plan for the area that includes a description of actions and commitments that will be taken to protect, enhance, and interpret the natural, historic, scenic, and cultural resources of the heritage area. The bill terminates the authority of the Department of the Interior to provide assistance with respect to the area after 15 years.