The $15 billion project is expected to open to passengers “later this year” with a soft launch using limited, off-peak services.
Premier Jacinta Allan has so far refused to give a firm opening date for a full-service timetable, not expected to be implemented until February.
Testing is under way and has included trials of services running as frequently as every three minutes in each direction.
However, the executive project director of the new tunnel, Ben Ryan, confirmed on Sunday when asked by The Age that a lengthy shutdown during testing on September 8 was “related to electromagnetic interference” or EMI.
EMI is when magnetic fields created by electricity disrupts the use of other devices.
The interference is an issue for many projects in urban environments, but has been a particular headache for the construction of the Metro Tunnel because of sensitive equipment, such as MRI machines and scanners.
The equipment is crucial to the work of medical and research facilities clustered around the new Metro Tunnel station at Parkville, with tens of millions of dollars spent trying to shield machines or move equipment to other locations.
Victoria also abandoned its plans for a major hospital precinct at the future Arden station, in North Melbourne, because of the cost of addressing EMI.
Authorities have also sought to reduce the current of the electricity running through the railway, which an Auditor-General’s report flagged could be reduced further.
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However, last month’s incident is the first time that EMI issues had emerged publicly in relation to activities within the tunnel itself.
The Victorian Infrastructure Delivery Authority would not provide details about the incident at the time, with a spokesperson previously saying the shutdown was the result of a “procedural” issue.
On Sunday, Ryan initially described the fault as “just a technical issue”. However, after repeated questioning from The Age, he ultimately confirmed the fault was EMI-related.
“It was related to electromagnetic interference, but we’ve sorted that out,” he said.
“We’ve got agreement with all the hospitals that the electromagnetic interference issue at Parkville that we’ve dealt with over a very long period of time, has been accepted by the three hospitals in Parkville (The Royal Melbourne Hospital, the Royal Women’s Hospital and the Peter MacCallum Cancer Centre), so it’s not going to affect the opening of the tunnel.”
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