Ontario gets ball rolling on Highway 401 tunnel feasibility study

Traffic uses 401 Highway in Toronto on Wednesday, January 3, 2024. THE CANADIAN PRESS/Chris Young

TORONTO — Ontario is taking a concrete step toward an idea Premier Doug Ford has championed to build a tunnel under Highway 401.

Ford has spoken often of the need to address gridlock and railed against lost productivity as a result of it. He first raised the idea last fall of building a tunnel under Highway 401.

In response to concerns about a project of that size potentially costing tens of billions of dollars he has said the province would do a feasibility study, however, he has pledged to get the tunnel built regardless.

“The reason we’re having a feasibility study is it’s going to determine the length. If they’re telling me, 30 kilometres is X, 40 kilometres is Y, and 70 kilometres or 60 kilometres is another cost, let’s take a look at it,” he said when he announced his plan in September.

“But we’re going to get the job done, mark my words.”

The province has now issued a request for proposals for a study to determine the feasibility of a tunnel and several other options including an elevated highway, adding more lanes and truck-only lanes.

It does contemplate the possibility of a tunnel or elevated highway not being possible.

“If no capacity expansion option is determined to be feasible, then congestion mitigation options are to be identified as alternative to expansion,” the request tells prospective proponents.

It also says the study should look to see how other jurisdictions have mitigated congestion, including an evaluation of high-occupancy vehicle lanes, bus-only lanes and truck-only lanes.

The request says the study should assess the larger options — including the tunnel — on a long-term horizon, specifying the year 2051.

The study itself is expected to be completed in February 2027.

Opposition leaders have suggested the tunnel will never actually get built and is a “silly” idea.

“His big priority is to get the feasibility study done on this silly tunnel under the 401, this imaginary tunnel,” NDP Leader Marit Stiles said Tuesday.

“I think that speaks to the fact that this premier still doesn’t really, I think, have Ontarians’ priorities clear in his mind.”

As part of the feasibility study, the province is also seeking a review of best practices from similar projects, including a proposed four-lane traffic tunnel in downtown Ottawa that never moved forward.

That feasibility study cost $750,000 and found that a 3.4-kilometre tunnel across downtown Ottawa would cost upwards of $2 billion in 2016 dollars. That tunnel has not been built.

The premier has said he wants to consider a tunnel from Brampton and Mississauga in the west to Scarborough and Markham in the east. The request for proposals says the study should also consider shorter tunnel lengths, such stop/start locations considering Highway 410 and 427, and Highway 404.

“Tunnel/elevated highway options should, as a minimum, consider connections (depending on tunnel/elevated highway length) to Highways 410, 427, 409, 400 and 404,” the request for proposals says.

The province is also looking to learn from the experiences of building the Channel Tunnel, a 50-kilometre undersea rail tunnel connecting England and France, as well as two tunnels built in Australia and one in Japan, plus elevated highways in Texas and India.

This report by The Canadian Press was first published April 29, 2025.

Allison Jones and Liam Casey, The Canadian Press