How to Fix a Troublesome Highway


When Montreal’s Turcot Interchange opened in 1966, no one had seen anything quite like it. Floating one hundred pillared feet above the ground, its concrete spans swirled and swooped through the air, finally coming together in a knot of jaw-dropping proportions. It comprised over seven kilometres of road and spanned an area of seventeen acres. Underneath its four levels of overpasses and elevated ramps, boats floated on the Lachine Canal and trains chugged with freight. In an especially futuristic touch, two continuous bands of fluorescent lights glowed from the highway’s walls. Driving on it, the city unfolded before you: a skyline studded with smokestacks and steeples and the slow blink of the Farine Five Roses sign. More than a mega-project, the Turcot was a Modernist victory cry.

The Turcot still inspires, but, like any relic of a bygone era, its sheen has worn away. The railyards that once spread out from the interchange—and from which the Turcot took its name—were closed by Canadian National in 2002. Ordinary highway lights replaced the space-age illuminations when the aluminum wiring decayed. Winter road salt has soaked the structure in a corrosive brine, inflating steel reinforcement bars into rusted balloons ten times their original size, causing concrete to fall off in chunks.

In 2007, the Ministère des transports du Québec (MTQ) proposed tearing the whole thing down and building a new ground-level interchange in its place. According to the renderings, vehicular capacity would be increased by 20 percent, but the new interchange—projected to cost $1.5 billion over seven years—would require the demolition of two hundred homes, including an entire street of walkup apartments and a large loft building that housed more than four hundred people. Its embankments would cut off links between St. Henri, Côte St. Paul and the other working-class areas adjacent to the interchange.

Unsurprisingly, the Turcot changes have proven controversial. Wander around St. Henri—the neighbourhood with the most to lose from the new interchange—and you’ll see “Mobilisation Turcot” posters everywhere, referring to the protest movement sparked by the MTQ’s plans. People are justifiably worried that the rebuilt Turcot will pump more cars onto their streets and more pollution into the atmosphere. But the Turcot has become more than just a local issue.

Over the past several years, Montreal has spent billions reinvesting in public transit and creating an impressive cycling infrastructure, including new bike lanes, on-street bike parking and a popular public bike-sharing system. The MTQ’s plan for the Turcot seems at odds with Montreal’s efforts to become more environmentally sensitive and less car-reliant. “The MTQ are focused mainly with getting cars and trucks to move as freely and quickly as possible,” explains Raphaël Fischler, an urban planning professor at McGill University. “They look at it from a very functional perspective. But their plan has to be pushed to be more environmentally sensitive, which means sensitivity to urban design as well as the natural environment.”

As it happens, the Bureau d’audiences publiques sur l’environnement (BAPE) agrees. After an assessment of the MTQ’s plans, the BAPE concluded they would have a negative impact on Montreal’s urban environment and ecology. So the MTQ must go back to the drawing board.

But what form should an alternative Turcot take? Other cities around the world, when faced with a similar dilemma, have come up with remarkable solutions. In 1976, Seoul built an elevated expressway over Cheonggyecheon, a stream that ran through the old imperial heart of the South Korean capital. Once a graceful canal, Cheonggyecheon found itself covered with roads and concrete as factories and warehouses sprung up along its banks after the Korean War. By the time the expressway was built, there wasn’t much of a stream left. Photos from the 1980s and nineties show a Cheonggyecheon Expressway clogged with cars and trucks making their way towards central Seoul’s forest of skyscrapers.

Safety evaluations soon revealed the expressway was deteriorating rapidly, and by 2001, $100 billion in repairs were needed just to keep the structure from collapsing. Rather than embark on what threatened to be an endless cycle of reconstruction, Seoul officials decided, in 2003, to go a different way altogether. In two years they demolished the expressway and roads covering the stream, restored two ancient bridges and created a beautifully landscaped park along the path of the water. Three decades as a virtual sewer had left Cheonggyecheon nearly dry, so 100,000 tons of water were pumped into the stream from a nearby treatment plant, giving it an average depth of about half a metre.

When the Cheonggyecheon reopened in 2005, its restoration had an immediate impact. In the summer, temperatures along the stream are more than three degrees cooler than in other parts of the city. Seoul’s own sense of itself as a fast-paced, ultra-urban city also changed. Cheonggyecheon’s banks are now lined by a promenade of wild grasses and rough-cut stone, giving the area a curiously rural feel, and stepping stones, placed along the stream at regular intervals, create a playful, improvisational quality. It’s now the kind of place where you’re likely to glimpse a canoodling couple roll up their jeans and wade in.

Most surprisingly, Cheonggyecheon has reduced traffic congestion. Not only has the number of cars decreased 2.6 percent since the expressway was removed, but more people now use the bus and metro to enter the city centre. It’s a perfect example of the Braess Paradox, named after mathematician Dietrich Braess, who noted in 1968 that adding capacity to a road network can sometimes result in a less efficient flow of traffic, and that reducing capacity can sometimes increase efficiency. One hypothesis is that, because drivers selfishly choose the route that seems shortest to them, the dispersal of cars between existing routes and newer, supposedly quicker alternatives results in more traffic jams.

This paradox was given another demonstration in San Francisco when the Embarcadero Freeway was demolished in 1989 and the Central Freeway knocked down in 2005. Against expectations, congestion improved.
 “What happened with the Central was that they had to temporarily close it to demolish the upper deck, and while it was closed, people got used to not having it around,” says Steve Boland, an urban planner who lives near the freeway’s former path. “On the day it closed, there were news helicopters hovering overhead, just waiting for the traffic apocalypse. But it never materialized. Drivers adjusted and either distributed themselves over the grid, or didn’t make as many trips.”

In Paris, an expressway has disappeared in a very different way. For most of the year, traffic rips along the Voie Georges-Pompidou, a limited-access arterial on the right bank of the Seine. Every summer, though, its lanes are converted into a 3.5-kilometre beach that combines the Parisian love of river lounging with the town’s summertime exodus for the beach. Sand is pumped over the roadway, palm trees are planted and chaise lounges set up along the riverside. With imagination and relatively little effort, a space reserved exclusively for cars and trucks is transformed into a delightful gathering place.

Paris-Plage’s popularity—its debut, in 2002, drew over two million people—proves that if you can’t raze an expressway, there are other ways to mitigate its impact. Last December, Hong Kong held an international competition to design a noise barrier for the Gascoigne Road Flyover, an elevated roadway that runs through one of the most crowded parts of the city. The winning entry—apparently inspired by the indigenous banyan trees that grow from old stone walls found in the hillier parts of Hong Kong—came from a team of local architecture graduates who proposed encasing the road in a tube of vegetation-covered glass slates. Not only would such a noise barrier make the neighbourhood around the road quieter, it would cut air pollution and create a kind of floating garden.

Why are all these unconventional highway solution relevant to the Turcot? Because they show that complicated infrastructural dilemmas require creative, out-of-the-box thinking, and that sometimes the most radical answer is the best one. Last year, a number of writers and academics published Montreal at the Crossroads: Superhighways, the Turcot and the Environment, a book on the challenges and opportunities presented by the interchange. One contributor, architect Peter Sijpkes, makes a bold pitch: don’t touch a thing. Sijpkes recommends we reinforce Turcot’s existing structure with steel beams, keeping it more or less unchanged, and open up the possibility of using the thousands of acres underneath it—empty space that would be wasted if the Turcot were replaced by a ground-level interchange.

Why not? Other cities have made good use of the space beneath their elevated highways. In London, playing fields, community centres and retail arcades were built below the Westway, which runs through the western suburbs. You’ll also find public markets and plazas under many flyovers in Hong Kong. In fact, if the Turcot is kept intact, other intriguing solutions emerge. It could be covered with plants to create the world’s largest vertical garden. It could be closed entirely to traffic and turned into a vast aerial promenade.

Nothing makes you feel smaller than standing beneath the Turcot Interchange. It was Montreal’s most ballsy foray into the Big Thinking era of the 1960s, when the march of history towards technological utopia was deemed inevitable. Things have changed since then. Montreal never morphed into the global metropolis it was destined to become, and grand, unilateral gestures are totally dépassé. But now that the BAPE has ordered the MTQ to rethink its approach to the Turcot, there’s no reason why that big thinking has to end.

This article first appeared in the Spring 2010 edition of Maisonneuve. For more about the future of the Turcot, see this Spacing Montreal post by Jacob Larsen outlining the latest plans.

This entry was written by Christopher DeWolf , posted on Thursday July 15 2010at 06:07 am , filed under Asia Pacific, Canada, Environment, Europe, Heritage and Preservation, History, Public Space, Transportation, United States and tagged , , , , , , , , , , . Bookmark the permalink . Post a comment below or leave a trackback: Trackback URL.

3 Responses to “How to Fix a Troublesome Highway”

  • Jason Prince says:

    A beautiful, lyrical take on this important Montreal debate. If Montreal had its say, the Turcot would indeed be significantly reduced in size and commuters would be accommodated via much improved mass transit (see ), but the final decision lies with the province of Quebec. Tragically, 2/3rds of the voters in the Montreal region live in suburbs…and they love their cars. Let us hope that health and environment trump “right to drive” when Quebec comes down with a decision.

    If you want to have your say, go here:

  • leave it intact and driving into montreal would be more like flying in kai tak in hong kong was. well, not quite but it would be pretty cool to have development right up to the highway.

  • I’m with you until that second-to-last paragraph, which seems to contradict all the earlier stuff about reducing highway capacity. Besides, I have yet to see any worthwhile development under & around highway ramps – if anything, all attempts have led to noisy alienating places that nobody wants to live near or have a picnic in. You can turn these spaces into creative urban art installations, but not create viable & sustainable places that people will want to see more than once.