Charting Canada’s major city conurbations

IT WAS ALMOST A CENTURY AGO that Patrick Geddes, a forward-thinking Scottish biologist, geographer and town planner, coined the term “conurbation.” Whether or not you’ve heard the word, you’ve undoubtedly seen, and quite possibly live in, one — an area where a number of once-freestanding cities or towns have grown together into a continuous agglomeration.

In this third and final entry in Canadian Geographic’s Canadian cities mapping series, cartographer Chris Brackley has mapped the conurbations associated with Vancouver, Calgary, Winnipeg, Toronto, Montreal and Halifax.

By definition, conurbations don’t line up with official political boundaries (although in the case of Halifax, its entire conurbation sits within its unusually far-flung regional municipal limits). Yet in many ways, they most accurately represent the area local residents think of as their “city.” That’s because conurbations are physical and functional entities. Their essential bonds are local transportation net- works and integrated labour markets. And we draw their limits where developments commonly associated with cities — roads, housing, retail, offices and industrial parks — end.

To create these maps, Brackley had to determine those boundaries himself — there are no official delineations. He used the presence of local roads as his primary guide, then added a 350-metre buffer to filter out small gaps between developments. “This seemed to be a contiguous urban experience,” Brackley says.

Because this is a subjective evaluation, readers who live in any of these six conurbations may view things differently. Does a single major highway bring a remote development into a conurbation? Can conurbations leapfrog gaps that are wider than 350 metres? What about rivers and small lakes? Brackley opted to ignore water bodies in particular, so urban spaces on two sides of a river or harbour are considered contiguous.

The shapes of the different conurbations are revealing as well, emphasizing patterns of development in relation to city cores and the underlying geography. They also reflect the flow of people and traffic and, in the process, offer clues as to the directions these conurbations might expand in the years ahead. Explore these maps and see what you discover.

Maps and text below by Chris Brackley.

This piece was originally published in Canadian Geographic’s May/June 2017 issue.