Thursday, August 16, 2012

Population Density Map for Toronto by Neighbourhood, 2011

Although the City of Toronto publishes all sorts of weird maps of Toronto, they haven't published a population density map using the most recent 2011 census data yet. They have published all sorts of related maps like population growth rate maps, senior maps, and children maps, but no matter how deeply I dig through their demographics website, I can't find a population density map using the 2011 data. But the City did publish the population of each of the 140 neighbourhoods in Toronto, so I thought I'd just generate my own population density map. I also grabbed Toronto's Open Data map information about the shape of each neighbourhood. So, all I needed to do was to parse the neighbourhood data and output it as svg. The shape data used a universal transverse mercator coordinate system, which means I could just calculate the areas of the shape polygons directly without really worrying about the curvature of the Earth and still get reasonable numbers. And from there, it was easy enough to calculate the population density.

Number of people per square kilometre (Contains public sector Datasets made available under the City of Toronto's Open Data Licence v2.0. Users are forbidden to copy this material and/or redisseminate the data, in an original or modified form, for commercial purposes, without the express permission of Statistics Canada. Information on the availability of the wide range of data from Statistics Canada can be obtained from Statistics Canada's Regional Offices, its World Wide Web site at: and its toll-free access number 1-800-263-1136.)
I sketched in the approximate locations of the subway (plus future extensions) so as to give the map some identifiable landmarks. The colour range is linear except for St. James Town, which had such a high population density of over 40k/km^2 that it skewed the colour range too much, so I had to treat it specially.

From looking at the City of Toronto's other maps, it looks like they have population data at a much more fine-grained level available, but I was restricted to individual neighbourhoods, which can be quite big at times and which sometimes encompasses mixes of large apartment blocks as well as low-density housing. Also, the data only shows residential density. The City has employment survey data which shows all the employment centres in the Toronto, but they don't have it in a form that I could process and overlay on top of this map.

The map is sort of limited, so it's not too interesting. I'm not sure if any interesting conclusions can be drawn from it. I guess I was previously curious as to why so much attention was being dedicated to improving transit in Scarborough in the east but not to Etobicoke in the west. But from the map, I can now see that the east end is much bigger with a higher population density, so it probably makes sense to focus efforts there. From the map, the case for a downtown relief line that extends north of Bloor in the east doesn't seem to strong since the density doesn't seem that great as compared to the west side, but the Don Valley could be screwing up the density numbers, and the density numbers don't include information about workplaces.


  1. Hi Ming. Would you be able to share the specific pop density values for Thorncliffe Park (55), Flemingdon Park (44), Crescent Town (61), Oakridge (121) and North St. James Town (74)? Thank you!

    1. The city of Toronto includes that information on their website in the ward profiles.