A sinkhole has formed above a cross tunnel passage, between the two Forrestfield Airport Link tunnels in Perth, Australia.
Currently under the construction, a leak was discovered in a cross tunnel passage between the twin-bored tunnels.
In a statement, Forrestfield-Airport Link said: “Immediate efforts were made to stop the leak, and this continued throughout the night.
“Despite these efforts, groundwater and silt is still flowing into the cross passage and one of the tunnels. A sinkhole developed immediately above the site, on Dundas Road about 200m north of the Forrestfield Station site. Dundas Road has been closed to traffic while work takes place to fix the leak and repair the road.”
Both tunnel-boring machines, which are more than 2km further on from this cross-passage, have been stopped while the repair work takes place. No one was hurt in the incident.
The AUS$1.86bn (£1.03bn) Forrestfield-Airport Link is jointly funded by the Australian and Western Australian governments and will deliver a new rail service to the eastern suburbs of Perth – with three new stations at Redcliffe, Airport Central and Forrestfield.
The line will spur off the existing Midland Line near Bayswater Station and run to Forrestfield through twin-bored tunnels. In April 2016 the Public Transport Authority awarded the design, construct and maintenance contract to Salini Impregilo and NRW Joint Venture. The project is due to be completed in 2020.