As part of the enabling works for Barangaroo Station development, Ferrycarrig delivered a range of complex utility relocations at Barangaroo for electrical 11 kV, communications, and stormwater augmentations. Ferrycarrig delivered all works around the station box ahead of schedule, despite facing challenging site conditions including a confined work area and complex design restrictions.
Ferrycarrig carried out the following works:
- Investigative works to locate existing services.
- Inground trenching and installation of 450m of electrical conduit.
- Design and installation of all temporary works for the 10m x 7m Ausgrid pit and stormwater pit.
- Excavation of the 10m x 7m in-situ concrete pit in rock, which included the excavation and removal of 700 tons of rock from the Ausgrid pit involving heavy plant and machinery.
- Removal and relocation of 2 sets of 11kV distributors to allow the tunnel boring machine to be installed.
- Removal and disposal of overhead cables and light poles.
- Creation of a design solution to install conduits and cable to the underside of a temporary 300m bridge.
- Pulling of new feeders to the Barangaroo mainland and laying of 500m of conduits, which allowed for the relocation of the new feeders that in turn powered the Tunnel Boring Machine
- Non destructive digging around live services to prove the location.
One of the key challenges associated with the works was the installation of conduits within a temporary bridge structure through a suspended steel encasement pipe. We innovated the design for a custom spacer, which was approved by the client and Ausgrid, which Ferrycarrig then fabricated in-house. The purpose-built spacer with wheels allowed us to pull the pipe into the deep pit and through the encasement without any damage and assisted in installing the conduits without the need for heavy machinery.
Our temporary works design allowed for excavations to the depth required for the Ausgrid 10m x 7m in-situ pit in hard rock, well before the commencement of the works. Works were carried out for 2 weeks over 24-hour shifts, using a 23t excavator. Rock was recycled into road base for re-use on the project. For unexpected heritage items found during excavation, an Unexpected Finds Protocol was established with the client early in the project.
Rather than constantly having to dewater the pit, a pump separation system and VAC unit were set up onsite, maintaining excavation safety and continuity in works while pouring concrete.
Due to the proximity of the bay to tidal waves, the client changed the concrete specifications to allow for a 100-year lifespan. Ferrycarrig accommodated these changes and met the program.
Ferrycarrig achieved all project targets and KPIs in the delivery of the project achieving the program that was crucial to the Tunnel Boring Machine could not have been launched, which would have been detrimental to the construction program. All works were carried out without injury or incident.