The Heron's Creek to Stills Roads project forms part of the Pacific Highway upgrading project. The project will upgrade the northbound carriageway of the Pacific Highway between Herons Creek and Stills Road, located between 53.5 kilometres and 57.0 kilometres north of the Taree interchange. The project involves the realignment of the north bound carriageway alongside the existing southbound carriageway and the associated construction of a new crossing over Cutty Creek and a new grade separated interchange at Bago Road (the Bago Road interchange). The majority of the existing northbound carriageway will become a two way local service road, linking Bago Road, Burrawan Forest Drive, Herons Creek and local properties to the Bago Road interchange. This addendum describes and assesses only those aspects of the project amended since approval of the original REF (RTA 2007a). The proposed design changes and proposed inclusion of construction elements for the proposal. This addendum should be read in conjunction with the original REF (RTA 2007a). The proposed design changes comprise: modification to the design of the Cutty Creek crossing; clarification and refinement of the design of the road connection between Herons Creek Road and the two way service road to the north of Herons Creek. Installation of a 1.5 kilometre high voltage reticulation cable; installation of a combined utility services route underneath Herons Creek and inclusion of construction elements required for the project.