Tunnel-boring machine still stuck beneath Toronto street while estimated recovery cost rises to $25 million

The cost to rescue a multi-million dollar boring machine trapped beneath a west end street has nearly tripled in just months, with city staff saying the work to unearth the device is more complicated than first anticipated.

The updated cost estimates and timeline come to Toronto's General Government committee next week. Documents show work to free a micro-tunnelling boring machine trapped under Old Mill Drive since last spring has jumped to $25 million — up from the approximately $9 million price tag in March.

City staff say additional groundwater infiltration at the site and the need for more soil stabilization have contributed to the soaring price and delayed the project. The machine remains trapped and work has taken about six months longer than first anticipated.

The latest delay isn't sitting well with residents who say they've struggled with a steady stream of heavy-equipment, dirt and vibrations from construction for years. The price escalation is the latest unpleasant surprise, said Tanya Boswick who lives on the street.

"I think every taxpayer in this city should be furious about the amount of money being spent on this project," she said. "There are lots of other communities and causes and needs that our city has to contend with."

Boswick said the community has been dealing with dust, noise and a constant flow of construction vehicles now for years. They want the project done, she said.

"It's really just the constant noise, constant vibration," she said. "And not to mention all the dust and dirt that's going around on top of the poor air quality. It has made this summer truly a nightmare for the people in this community."

Iain Downie lives in a condominium building next to the job site. His apartment looks out over the work.

"We can't sit outside on our balconies," he said. "We're cleaning everything constantly because of the dust. We're changing indoor air filters regularly because it's just coming right in."

"And we're just having to hear everyone in the neighbourhood be really miserable, that's really not fun."

The work to dig a new storm sewer on Old Mill Drive began in March 2022. The project was designed to address chronic basement flooding in the area. City staff opted to use a remote controlled micro-tunnelling boring machine, which is 1.5 metres wide and five metres long to create the new sewer tunnel.

The plan was for the machine to be placed 18 metres below ground and have it travel 282 metres to a pre-constructed exit shaft on Bloor Street West. Workers needed to place it deep underground to avoid coming into contact with the nearby Bloor-Danforth subway line.

But with just seven metres left to go on its route, the machine hit 14 underground steel tiebacks which had been part of the construction of a nearby condo building. It became ensnared in them, and is now twisted and turned off course.

Cost to rescue machine jumps by an additional $16 million

The initial work to dig the new sewer tunnel was budgeted at $7.2 million. In March, the city signed off on a sole-source deal to extract the machine for an estimated $9 million.

The new report says costs have jumped by an additional $16 million to $25 million.

The city says the latest figures are based on estimates and represent "the possible costs required to complete the emergency work."

"The final costs and actual payments will be based on substantiated and certified invoices," the city said in a statement.

Contractors had hoped to rescue the machine by early April. The rest of the sewer work is estimated to be completed by the fall.

It's believed that workers will be able to pull the machine from the ground by late August.

The city says that as contractors were hand-digging to rescue the boring machine they encountered more water than anticipated.

"In order to safely proceed with the removal of the machine, the water needed to be removed and the surrounding ground area stabilized," the city said in a statement. "This required an expert in ground improvement and stabilization."

Coun. Gord Perks said the water infiltration has been a problem and wet weather hasn't helped matters.

"When there's a big rainstorm the work that they're doing to try to get the tunnel boring machine out gets compromised," he said.

Perks said he understands residents' frustration with the project. He's arranged more frequent city meetings with the neighbourhood to keep people apprised of the situation.

"It is entirely fair for people to be upset that a project that was supposed to be over in six or eight months drags on and on and on," he said. "That's completely understandable. But there is no magic, cheap solution here. This is going to cost some money."

Coun. James Pasternak is the chair of the city's general government committee. Councillors will be asking pointed questions of city staff on Monday, he said.

"This is a shocking amount of money," he said. "Now, I do realize that the work that has to be done is extremely risky and sophisticated."

Pasternak said the work is urgent and must continue to ensure that the roadway around the site doesn't collapse. But he's hopeful lessons can be learned from this situation.

"We're going to be asking some tough questions about why sole source, why it's so much money, and what the options are for recovering these funds through litigation," he said.