Here's the thing, growth does not equal sprawl. I don't think it's fair to compare New York to Calgary even if their land mass is similar. The characteristics of the cities and what's around them is completely different. Manhattan is an island for example, you can't build on water (yet) so it's more confined, whereas Calgary is on prarie ... I *think* you can build on land
Now, I'm not framiliar with Calgary, I've been there twice. Once was in the winter when it was cold, and once was for less than 24 hours on this date 2 years ago (the planning of the city, while I paid minor attention wasn't my focus... hmmm wonder why?).
Sprawl is outward growth without the planning and foresight to keep the downtown core in tact. It's like dropping a rock in a pool of water, and not having a ripple effect of the wave moving outward, but all the water period so the rock ends up dry with a moat of water surrounding it.
It's hard to gague sprawl in booming cities, as well they're booming, that can skew the perception. From what I understand (based on the two threads on skyscrapers in Calgary) that the downtown core is booming. As long as the high density boom can equate for the low density suburb boom then that's ok. A city will naturally be high density in the middle and shrink outward.
Halifax is booming right now, they have development like Bayers Lake, and the new Dartmouth Crossing, that I'm not a fan of, however the downtown is still vibrant, and new buildings are constantly going up. I don't see sprawl being a problem in Halifax... well... ever, unless the universities (5 on the Halifax peninsula) die or something.
If the business skyscrapers are compensating for the living quarters that people are living in, if there is interaction, hussel and bussel downtown, and if the city is vibrant after office hours, then I wouldn't worry about Calgary's growth.
However, I've never really been through the city, and am not framiliar with its growth patterns, tax rates, low value, high crime areas.
In short for those framiliar with the term social captial, sprawl causes negative social capital. There's good growth and bad growth, but I can't tell what Caglary had (again being an east coast boy not overly framiliar with the city, on a related topic... what the hell is a kanasis?

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