Daily London
The collapsed turf was seen at AJ Burkitt Oval in Heidelberg on Monday afternoon, drawing a crowd of onlookers.
Victorian Infrastructure Delivery Authority (VIDA) chief executive Duncan Elliott said yesterday two tunnel boring machines digging underground as part of the North East Link were located metres from the site.
Engineer and former president of the International Tunnelling and Underground Space Association Arnold Dix told Today he would bet that the project and the sinkhole were linked.
“A sinkhole on the surface also means that there’s possibility of difficulties underground, so we’ve got to think of our people underground and their safety and of course, the safety of people up on the surface,” he said.
“So something’s gone wrong.
“And some serious questions have to be answered about how it’s gone wrong, why it’s gone wrong, to make sure it doesn’t happen again.”
He said that such a sinkhole posed a “serious risk”, noting that the oval appeared to have been recently mowed.
“If I was mowing that oval and it had collapsed and I went in, that’s really serious risk,” he said.
“You could be you could be seriously injured or killed if you fell into it.”
But he said the oval would be safe to use again once the issue had been identified and corrected.
“It could be a change in the movement or the ground level of water underneath,” he said.
“It could be that they’ve had more material go into their tunnel boring machine than they were expecting. There’s a whole range of reasons for it.”
However, he said, the fact that the sinkhole had not yet expanded – though he noted that was a possibility – and the fact that nobody had yet been injured, meant it was the sinkhole he’d like to see in his backyard, if he had to have one.
“This is the cute and cuddly sort, this one,” he said.
“Let’s keep it that way.”
A North East Link spokesperson yesterday told 9news.com.au they were aware of the sinkhole “in the vicinity” of the tunnelling operation.
“The area has been secured and crews are closely monitoring the site and surrounding areas – and we strongly advise people to avoid the area while investigations into the cause are underway,” they said.
“No injuries have been reported and there is no immediate threat to the community or residential properties.”
