Discovery of a deep sink hole in the middle of the $26bn North East Link shuts down construction

Work on Victoria’s most expensive road project, already running $10bn over budget, has ground to a halt after the shock discovery of a 20m deep sinkhole.

Construction on the $26bn North East Link has been shut down after crews discovered a deep sinkhole in the middle of the project.

The shock discovery was made on Thursday night as one of the project’s two tunnel boring machines was moving towards Lower Plenty Rd.

Tunnelling for the mega road project is underway, with two boring machines digging at the same time to create twin 6.5km tunnels from Watsonia to Bulleen in Melbourne’s northeast.

The North East Link, which is Victoria’s most expensive road project, will connect the M80 Ring Rd with the Eastern Fwy.

A sinkhole has stopped work on the North East Link. Picture: Supplied

The sinkhole stopped the work of a tunnel boring machine. Picture: Supplied

The Herald Sun has been told the first boring machine, which was headed in the direction of Lower Plenty, struck a sinkhole.

That sparked an emergency response and caused the project to immediately grind to a halt.

No one was injured.

Crews on Friday were working to ascertain how the boring machine can be moved past the 20m deep hole, until it can be filled.

Sources familiar with the project said an exclusion zone would be created around the sinkhole.

It’s understood the second boring machine was not impacted as it was not operating due to a planned maintenance period.

The North East Link is Victoria’s most expensive road project. Picture: Supplied

The project is running $10bn over budget. Picture: Supplied

Major Road Projects Victoria told the Herald Sun a “surface hole” had been detected at the Lower Plenty worksite.

“There is no risk to the community or property,” the agency said in a statement.

“Works temporarily ceased in the vicinity. TBM (Tunnel Boring Machine) 1 is operating with additional shift engineers to move it beyond the surface hole to a safe zone. TBM 2 operations have paused.

“Surface remediation works will be undertaken later today.

“The cause at this stage is under investigation.”

Transport Infrastructure Minister Gabrielle Williams said she hoped construction would be up and running within days.

But Ms Williams said the stop work call was made out of an “abundance of caution”.

“We’ll have our expert engineers running a very thorough investigation to try and understand exactly what’s happened and why,” she said.

The second TBM, which is located underneath the sinkhole, was “effectively laying out concrete rings to secure the ground” on Friday afternoon, Ms Williams said.

“It will then also cease temporarily,” she said.

Ms Williams said the sinkhole had occurred at an old army barracks and there was no risk to property.

“The site is safe,” she said.

“The team down there are taking an abundance of caution which is appropriate in terms of ceasing operations on the site while they do the investigation.”

WorkSafe and engineers were on site on Thursday night.

The North East Link was first spruiked in 2016 to cost just $10bn but was later revised to $15.8bn when designs were locked in.

In December 2023, the government conceded the cost of building the project had again blown out to now weigh in at $26bn.

The project is expected to open in 2028.

Originally published as Discovery of a deep sink hole in the middle of the $26bn North East Link shuts down construction