The Economist recently published an essay called, A Planet of Suburbs — The world is becoming ever more suburban, and the better for it. The argument is basically that the "great urbanization" that everyone loves to talk about these days is actually a misnomer. From Chicago to Chennai, it's not the urban core that's growing. It's the suburbs. And so what we're seeing should actually be called the great suburbanization.

The basis for this argument is that wealth fuels sprawl. As people become richer, they naturally consume more of everything — including space. It's a natural market outcome.

Take for example, the path of many of Toronto's ethnic groups. In the first half of the 20th century, College Street was the Little Italy. Then it shifted north and St. Clair Avenue West became the more authentic Little Italy. Today, many Italians now live north of the city in Woodbridge. In fact, last weekend I was on St. Clair West and was disappointed to learn that one of my favorite butchers had closed up shop and "moved to Woodbridge."

However, there are also many supporters of the exact opposite outcome. From Edward Glaeser to Alan Ehrenhalt, many have argued that we're in the midst of a "great inversion." The suburbs are no longer a threat to urban centers. It's the urban centers who are threatening the suburbs. The suburbs are dead. Long live the city.

So which is it?

Well, The Economist does cite two examples where true urbanization is actually taking place. It's happening in Tokyo and London. In both cases, it's the city center that is growing the fastest — not the suburbs. The explanation for Tokyo is its aging population. And the explanation for London is its restrictive greenbelt, which effectively stops the possibility of any further sprawl.

Here in Toronto — where there is also a greenbelt in place — we know that the population of the downtown core is growing at an incredible pace. A recent report by the city — called Comprehensive to the Core — revealed that the downtown core is growing at 4 times the rate of the rest of the city.

But what about the suburbs?

If we look at the province of Ontario's growth projections, it is indeed the suburbs which are expected to grow the fastest up until 2036. Here is a diagram showing percentage growth rates:

In absolute numbers, the city of Toronto alone is expected to add about 0.66 million people between 2012 and 2036, and the suburbs are expected to add almost 1.9 million.

There are a number of potential explanations for this differential, but I think it's largely because land is cheaper in the suburbs, it's easier to add new housing supply, population densities are lower, and we're talking about very different land areas.

The city of Toronto is 630 square kilometers. If you tack on the suburbs, the Greater Toronto Area is 7,124 square kilometers. That means Toronto makes up less than 9% of the total land area. And yet it is expected to contribute 25% of the region's population growth. 

Still, the suburbs are where the bulk of the population growth is expected to happen over the coming decades.

However, the "great inversion" that authors like Alan Ehrenhalt have been talking about should not really be interpreted as the death of the suburbs. What he's instead talking about is a socioeconomic or demographic reversal: center cities used to be poor and now they're becoming rich.

Here's how he put it:

What we are seeing is a reversal in which the words "inner city," which a generation ago connoted poverty and slums, [are going to mean] the home of wealthier people and people who have a choice about where they live, and the suburbs are going to be the home of immigrants and poorer people. And Census figures show that that's taking place.

In this context, we are still living through the great urbanization. We're seeing a shift in consumer preference and a shift in where wealth is choosing to locate. That's a profound change.

And while we're obviously still suburbanizing, I don't agree that we're better for it. In fact, left unchecked, this demographic inversion could actually prove to be quite damaging to our suburbs.

Image: Flickr