Tunnelling at Forrestfield, the site that hosts the infrastructure vital to tunnel boring machine (TBM) operations, began in August (TBM Grace) and October (TBM Sandy) 2017. The site is operating 24 hours a day to support tunnelling activities, including processing excavated soil and treating water for re-use in the tunnelling process.
In a bid to unite the divided construction site at Forrestfield (dive structure, stowage area construction and station works to the west – TBM operations to the east), a section of Dundas Road has been realigned and is now open. The road changes will allow backfilling of the station retaining wall to continue. View a map of the changes to Dundas Road.
The 300m long retaining wall for Forrestfield Station is almost completed, with 89 of the 93 panels in place. The remaining four panels will be installed once the multi-service vehicles no longer require access to the tunnels. More than 100 counterforts are being used to keep the 8.2m high wall securely in place. The counterforts support the 18 tonne wall panels, as well as the backfilling which is required to raise the ground level at the station by up to 6m.
Work is also continuing south of the site where stowage foundations and rail embankments are being prepared and utilities installed. Pouring of the platform sections has commenced with eight out of 32 completed. The stowage yard will be the end of the Forrestfield Line, where trains will be cleaned and maintenance will be undertaken.
Starting late-September waterproofing injections will commence on the sealing ring beams installed around the tunnel entry and exit at the Forrestfield dive structure.