Path Dependence

Richard Harris has taught urban geography at UBC, the University of Toronto, and McMaster University. He has written about the history of housing, urban development, and the social geography of cities in North America, India, and Kenya since the late nineteenth century. His most recent work is How Cities Matter (Cambridge University Press, 2021). He is currently writing a history of Canadian neighbourhoods, city and suburban, since the 1880s.

Toronto’s Inner Suburbs: An illustration of path dependence

Path dependence is a formal way of saying that the past shapes the present. What the definition alone does not reveal is that this influence is often forgotten, or simply overlooked. There are countless examples, but one that illustrates this influence clearly is the built environment (Harris, 2021). The inner suburbs of Toronto, Ontario are a case in point.

In the 1980s, these suburbs found international fame. The Toronto Transit Commission (TTC) had some of the highest per capita ridership levels in the world. American and Australian experts came to the city, hoping to learn what the Commission was doing right. They were especially intrigued by the fact that ridership rates were high in the suburbs that lay just beyond city limits. These suburbs included North York, East York, Scarborough, and Etobicoke, municipalities that were merged into an expanded City of Toronto in 2000 and which today are often referred to as Toronto’s inner suburbs.

The foreign experts did not realize that the TTC benefitted from decisions made before it even came into existence. Many parts of those inner suburbs were developed in the first three decades of the twentieth century (Harris and Lewis, 1998). At that time, the streetcar system was privately owned by the Toronto Railway Company (TRC). The TRC had a franchise which gave it a monopoly on streetcar service until 1921. Its most profitable lines were those that served the central business district and inner city neighborhoods, where ridership levels were highest. Its directors knew that extending lines into fringe areas that were largely undeveloped would be unprofitable. Despite pressure, they therefore refused to expand the system.

At that time, almost everyone walked or took transit to work. Even middle-class families could rarely afford a car. Suburban land developers knew that they would have to create high-density subdivisions so that as many people as possible would be able to walk to the end of the nearest streetcar line. They created innumerable gridded streets of 25-foot lots, or narrower. These were situated beyond city limits in semi-rural municipalities that could not afford to install piped water and sewers. Because small lots on such streets, coupled with long walks on muddy streets, were unappealing to middle-class male commuters (and their wives), these early suburbs were settled at high densities by working-class families. For many, the only way they could acquire a home was to build their own.

In 1921, when the TRC’s franchise ended, the publicly-owned TTC took over. Responding to demand, it soon extended lines into areas that had by then become half-developed, but the die had been cast. More homes were built in the 1920s, and indeed some in the early post-WWII years, on narrow lots in the subdivisions laid out before 1921. The result was high-density settlement. Servicing those suburbs has never been ‘profitable’, but it was at least feasible: it required much less public subsidy than if those areas had been developed at the lower densities that became typical across Canada after 1945. That is why, in the 1970s, it was feasible to provide those areas with good transit service, as indeed it is today.

The visiting experts from Australia and the U.S. overlooked this back story. They worked hard to figure out what lesson they could take from the TTC, without recognizing that the main influence was historical and now well beyond control. They had missed the bus—actually, the streetcar—by more than half a century. The TTC’s later success depended in large part on the shrewd caution of its privately-run predecessor, the TRC.

There is nothing extraordinary about this story. The built environment is durable, shaping peoples’ lives for decades, or centuries. That is why cities endure long after their original reason for existence has gone (Briggs, 1968; Polèse, 2009). That is also why many planners and environmentalists worry about the lower-density post-WWII suburbs that are built around the car. Reducing their carbon footprint is not easy. Just as important are the institutions in Canada that frame our built environment, including private property ownership, zoning, and democratic municipal elections (Sorensen, 2015). Although redevelopment happens, it is tricky and expensive, especially when it requires the assembly of multiple lots or the insertion of multi-unit buildings into single-family areas, which can provoke NIMBY (Not-In-My-Back-Yard) opposition. Gentrification, which involves the influx of middle-class households into lower-income and immigrant neighbourhoods, has become common in older areas of Toronto and some other cities, but the legacy of the built environment still has an impact. Gentrifiers favour houses, streets, and neighbourhoods with ‘character’, or else old warehouse districts ripe for ‘loft living’. Indeed, there is no part of any city, least of all the street network (whether gridded or not) which is path independent.

Path dependency is not unique to the built environment. Have you ever wondered why we all type on a keyboard layout (known as QWERTY) that was designed to be inefficient? The answer is that, when people were using typewriters, the spokes that carried the metal letters to the paper would get tangled if people typed too quickly (Diamond, 1997). And why do CN and CP—like most train companies around the world—use a rail gauge (the width of the rails) that is suboptimal? Because, two hundred years ago, it was the standard for horse-drawn coal carts in the north of England (Puffert, n.d.). Again, the answer is happenchance, combined with historical inertia. The examples are endless. In all spheres of life—economic, political, social, and cultural —the past matters.