Ultegra were contracted by Ausgrid to design and install an 11kV submarine cable between Catherine Park on Scotland Island and a location adjacent to Halls Wharf at West Pittwater. This project required the cable to be installed in underground ducts at each shoreline and embedded in the sediment of the Pittwater body of water with the three main components of this project including:
HDD
- HDD from Catherine Park at Scotland Island approximately 200 metres
- Installation of 180mm PE conduit
- All associated Welding and de beading
Marine Operations
- Barges used to transport large plant, equipment and materials
- Light boats used to monitor boring head
- Dive teams used for underwater operations
Civil and Electrical
- Trenching and excavation for underground cables
- Cable handling & hauling
Key Achievements
- Successful fracking management to ensure there was no major environmental impact
- Working with a marine engineer to get a report and a design for the barge layout to ensure it was able to hold the 30T cable drums well as transport heavy machinery to and from the island
- Specialised cable drum stand and cable hauling equipment
- Specialised submarine cable pulling eye
- Coordinating the works with the diving team. There were two divers in the water at all times – one checking the cable was laid properly on the sea floor and the other one monitoring the angle of the cable entering the water as to not damage the cable
- The divers used specialised jet blasters to bury the cable 1.5m into the sea bed and protectorshell was used where they could not reach a depth of 1.5m