Walkway under construction
Main Cable Anchor Footing
Rockfill wall walkway
The construction of a pedestrian bridge across the upper reaches of Cockle Creek near Bobbin Head NSW, a vital link of the Mangrove Boardwalk through the Ku-ring-gai Chase National Park, posed many environmental & construction difficulties for the National Parks & Wildlife Service of NSW. These issues included the need to preserve the pristine mangrove swamps, aboriginal artefacts and middens along the alignment of the proposed boardwalk & bridge.
Shirley Consulting Engineers proposed that the bridge structure comprised an anchored supporting pole on one side of Cockle Creek, with the pedestrian bridge being supported by cables from the anchored pole secured into the bedrock. SCE also proposed that the bridge structure be prefabricated and then transported into position by barges.
The design & construction of the bridge was then undertaken by the NPWS themselves under SCE review. When the bridge was opened, the minister complemented both the NPWS and SCE for delivering a difficult project on time, and within budget.