Perth Airport rail link completion delayed to late 2021; Skybridge being built to connect to Terminal 1
David Eyre 
Artist impression of Airport Central Station, looking northeast. Photo © State Government of Western Australia.
16 June 2019 © David Eyre
Completion of the $1.86 billion Forrestfield Airport rail link will be delayed to late 2021, following a number of incidents affecting its timeframe.
The Forrestfield-Airport Link is the largest tunnel project ever conducted in the Perth metropolitan area.
Incidents
Tunneling began in October 2017, but was paused for two months from late February 2018, due to ground disturbance issues.
A sinkhole developed in September 2018, with flooding and soil slippage as the tunnel boring machine (TBM) worked on a cross tunnel passage along Dundas Road on the east side of Perth Airport. The contractor Salini Impregilo-NRW apologised, indicating the incident was caused by defective work. This incident sparked safety concerns and criticism from the Construction, Forestry, Maritime, Mining and Energy Union (CFMMEU)
In December 2018, the CFMMEU allegedly organised an illegal strike across Forrestfield, Bayswater and Redcliffe Station sites, in a dispute over the payment of redundancies at the end of the project.
On 14 May 2019, tunnelling operations paused after a section of piping servicing tunnel boring machines (TBM) Sandy dislodged in Tunnel Two, causing a slurry spill.
Progress update
Planning for Forrestfield-Airport Link began in 2008. The project was launched in August 2014, following approval from the State Government and in April 2016, Salini Impregilo-NRW Joint Venture (SI-NRW) were awarded the $1.176 billion contract for design, construction and a 10-year maintenance period once the project is complete in 2021.
The TBMs began tunnelling two separate tunnels at Forrestfield in mid-2017 and reached Airport Central, 17 metres underground, on 8 May (TBM Grace) and 19 May 2018 (TBM Sandy).
By late 2018, the two tunnel-boring machines finished digging under the runways at Perth Airport. Tunnelling under an operating airport has only ever been done a few times across the world, so this was a significant milestone.
TBM Grace continued west, arriving at Redcliffe Station site on 9 May 2019, 12 metres underground. It has now tunnelled 62% of the 7.4 kilometre tunnel which is part of the 8.5 kilometre train line to Bayswater.
TBM Sandy is currently about 200 metres behind Grace and is expected to reach the Redcliffe box in June 2019. Both TBMs will remain at Redcliffe for six weeks, for maintenance.
Both machines will then begin the final leg of their journey, tunnelling to a depth of 22 metres under the Swan River and on to Bayswater, where it will eventually connect to the Midland Line.
Skybridge
In November 2018, construction began on the Skybridge, an elevated walkway with travelators and lifts for passengers to move between Airport Central Station and Terminal 1.
Any reason the airport station could not of seen a seamless walk from the station platform level through to the terminal via a tunnel walkway and then up to the terminal main concourse. Better still have the station stop under or closer to the terminal. Now they have to go up two levels walk across the skywalk and come back down again.