Ontario Urban Cores 1956-2011 Population Trends

It's often said that Canadian cities didn't experience as intense urban decline as American cities. So, after looking at how American urban core populations changed by neighbourhoods, in the Rust Belt and other cities that experienced population loss (+Montreal), here's a similar analysis of Ontario's largest cities.

Although I could find 1951 data for Toronto, Ottawa, Windsor and London, I could only find 1956 census tract data for Hamilton and Kitchener-Waterloo, so I decided to do the comparison from 1956 to 2011 for all of these cities.

Since the American analysis started with Detroit, lets start with it's Canadian sister city, Windsor. Like Detroit, Windsor in the 1950s was a major centre of auto-manufacturing.

These are the census tracts that make up the 1951 Windsor city limits. A big reason why Windsor didn't experience much population loss was annexation, within these city limits, population loss was relatively significant throughout. Only one census tract at the outskirts gained population, and not much. Downtown fared a bit better than adjacent neighbourhoods, which have some vacant lots although not too many as in Detroit.

1956 Population: 122,980
2011 Population: 82,324
1956-2011: -33.1%

Driving on highway 401, the next major city is London, Ontario.

London fared about the same as Windsor. For the 1951 city limits, only one census tract on the fringe gained population, and the downtown actually lost more than Windsor's. London had a variety of manufacturing South of Downtown and in the Eastside. I'm not sure what happened in the CT that lost 79.5% of its 1956 population. This census tract recorded a huge population gain from 1951 to 1956, then a sharp loss from 1956 to 1961 and gradual losses following 1961. Maybe something related to the military base there?
1956 Population: 101,693
2011 Population: 69,533
1956-2011: -31.6%

The next city along the 401 is actually two twinned cities, Kitchener and Waterloo.

Though it has caught up now, Kitchener-Waterloo was at the time smaller than London and Windsor, and the 1961 city limits were more expansive, taking in a significant amount of rural land. Also, unlike London and Windsor, the census tract that lost the most is actually Downtown. The surrounding neighbourhoods experienced more moderate population losses than in London and Windsor.
Kitchener 1956: 60,916
Waterloo 1956: 17,095
Kitchener 2011: 110,918
Waterloo 2011: 41,020
Kitchener 1956-2011:  +82.1%
Waterloo 1956-2011: +140.0%

The 12 central census tracts (those that grew least) would probably be more comparable to the 1951 city limits of Windsor and London.
Central K-W 1956: 51,627
Central K-W 2011: 41,364
1956-2011: -19.9%

Not far South from K-W is the city of Hamilton at the Western end of Lake Ontario.

For Hamilton, Toronto and Ottawa, census tracts were combined into larger neighbourhoods since they're bigger cities and it would be too difficult to show all the CTs. Though Hamilton suffered from loss of industrial jobs, such as those that were in the steel mills that feature prominently in its harbour, Hamilton is the first city so far that gained population in its downtown. Downtown Hamilton is home to a significant number of post-war apartment buildings, including dozens of highrises. The harbour lost a significant amount of population, as did the Barton corridor, both of which are gritty working class/industrial in character. Other core neighbourhoods experienced more moderate population loss, with major population gains in fringe areas since Hamilton's 1961 city limits were fairly expansive.

Hamilton 1956: 250,914
Hamilton 2011: 341,245
1956 - 2011: +36.0%

The 9 more central neighbourhoods that experienced relatively little (or no) greenfield development:
1956: 224,179
2011: 168,889
1956-2011: -24.7%

Next is Toronto. This map shows the city with the 1961 city limits, as well as inner suburbs that were more or less built out by 1956: Weston, York, Forest Hill, Swansea, Leaside, East York.

Population gains in Downtown Toronto were much greater than in any other Ontario city. Even Midtown gained a fair bit of population through intensification. This is despite the fact that household size changes seemed to have a significant effect in at least some neighbourhoods. Little Italy lost 43.2% of its 1956 population for instance. Gentrification may have played a role too in Little Italy, since the adjacent neighbourhoods saw lower losses despite relatively little new intensification. Certain outer neighbourhoods gained population, which may have been partly greenfield development, but I suspect highrise construction in the 60s and 70s was more significant, as all of these neighbourhoods have several highrises. Old East York and Parkdale saw several new highrises built, but it appears to have been insufficient to counter declining household sizes.

Total Inner Core
1956: 905,353
2011: 987,117
1956-2011: +9.0%

While you could make a case that the inner suburbs saw a bit of greenfield development, the Old City certainly did not, it was already close to built out in the 1910s, and essentially completely built out by 1930.
Old Toronto (doesn't include Swansea and Forest Hill)
1956: 664,002
2011: 693,295
1956-2011: +4.4%

Finally, there's Ottawa within the 1961 city limits, as well as Hull (1961 city limits), and the inner suburbs of Vanier and Rockcliffe Park.

Although Ottawa was not as much of a manufacturing city as Kitchener-Waterloo, Hamilton, London and Windsor, the population trends more closely resemble those of these cities than Toronto's. Downtown (surprisingly) lost population though not as much as adjacent neighbourhoods, and only the outer neighbourhoods gained population.

Ottawa proper + inner suburbs
1956: 294,418
2011: 399,258
1956-2011: +35.6%

Ottawa proper
1956: 243,509
2011: 354,331
1956-2011: +45.5%

Hull lost a lot of population in the inner neighbourhoods, but the area inside the 1961 city limits fared better thanks to greenfield development.
1956: 50,909
2011: 44,909
1956-2011: -11.8%

Vanier-Rockcliffe Park
1956: 21,380
2011: 18,279
1956-2011: -14.5%

Looking at the more central neighbourhoods of Ottawa (those that lost population) this is how they add up. Surprisingly similar to Hamilton despite feeling less gritty.
1956: 161,853
2011: 123,563
1956-2011: -23.7%