High-speed rail line could see long tunnels beneath Montreal, Toronto

A planned high-speed rail line between Toronto and Quebec City will include tunnels in Montreal and possibly Toronto, says the Crown corporation overseeing the undertaking, whose budget some experts warn may be stretched as a result.

In an update on its website, Alto says it plans to burrow from just north of the river that rims Montreal’s north side to downtown in a north-south corridor that would exceed 10 kilometres.

“To reach Montreal, the current hypothesis involves building a tunnel under the Rivière des  Prairies and Mount Royal to access downtown directly, reducing integration challenges in a dense urban setting,” states Alto’s preamble to an online survey about the proposed railroad.

It is also considering tunnels or elevated tracks to reach downtown Toronto “from the north or the east,” terminating at either Union Station or a nearby location.

Rail tunnel construction has proven a pricey undertaking in recent years, ballooning the budgets of Toronto’s Eglinton Crosstown light-rail line and Ontario Line subway plans as well as Ottawa’s Trillium Line.

The Eglinton line’s budget soared beyond $13 billion from an initial $5-billion estimate, due to a slew of complex challenges that included moving gas and water pipes. More than 10 kilometres of the 19-kilometre Eglinton line are underground. The bill for that project works out to nearly $700 million per kilometre.

For Montreal’s Blue line metro extension, it tops $1 billion per kilometre.

So would the cost of a high-speed rail tunnel through Montreal, said Ahmed El-Geneidy, a professor at McGill University’s School of Urban Planning.

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As it stands, the proposed tunnel would account for between 12 and 18 per cent of the project’s budget, estimated at $60 billion to $90 billion.

“It’s very hard from a civil engineering standpoint and from a safety standpoint,” El-Geneidy said.

“We’re not talking about the standards of the 1900s when we built the Mount Royal Tunnel.”

In its update, Alto also said it’s weighing two possible corridors between Peterborough, Ont., and Ottawa. One is a more direct line between the two cities and the other curves south, closer to Lake Ontario.

Construction of the first phase of the 1,000-kilometre corridor is set to kick off in 2029 or 2030, linking Montreal and Ottawa in an effective test case for a massive infrastructure project intended to transform rail travel in Canada’s most densely populated region.

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