About the site
A temporary retrieval site is required for the removal of the tunnel boring machine (TBM) cutter heads and shields at Blues Point Reserve. Once tunnelling is completed the site is being backfilled and the parkland reinstated in consultation with North Sydney Council.
Main site features
Construction activities include:
- Setting up site fencing, hoarding, site sheds and amenities
- Removing the TBM: lifting out the cutter heads and shields as they arrive
- Diverting utilities like water, sewer, gas and electricity if required
- Excavating the shaft with excavators, rock hammers or blasting
- Removing spoil
- Backfilling the area and reinstating the park once tunnelling is complete, in consultation with North Sydney Council.
Excavation takes around 12 months, and afterwards, the site is only to be active when a TBM arrives and when the park is reinstated. There are four retrieval events, taking about four weeks each. Two TBMs arrive from Chatswood and their cutter heads and shields are removed at Blues Point, and the rest of the TBMs pulled back through the tunnels and removed from the Chatswood dive site.
Next, the specialised TBM arrives from Barangaroo and its cutter head and shield are removed at Blues Point and the rest of the TBM is pulled back through the tunnel to Barangaroo where it is rebuilt and begins work on the second tunnel.
The cutter head and shield are removed again at Blues Point and the rest of the TBM pulled back through the tunnel to Barangaroo. Trucks remove the cutter heads and shields from the site over a number of days. This usually occurs at night to minimise the potential impacts to traffic on Blues Point Road.
Once a TBM arrives, the cutter head and shield is removed using a crane and placed on an oversized truck to transport the TBM cutter heads and shields away from the site. During retrieval of the TBM cutter head and shield, the temporary site expands to include the parking areas on Blues Point Road adjacent to the reserve. Additional car parking spaces are sometimes required temporarily for short periods of time along Blues Point Road. Bollards may need to be removed from the roadway to accommodate the oversized trucks.
To minimise potential impacts to the local road network, investigations are being undertaken into the possibility of removing the TBMs and spoil via barge, using the wharf at the end of Blues Point Road. To use the existing wharf for TBM removal, an upgrade to the wharf facilities may be required.
The temporary site is located at Blue’s Point Reserve, North Sydney, with access via Blues Point Road (left-in) and Henry Lawson Avenue (left-out).