Mapping Urban Density in Sydney

Published on Saturday, July 20, 2013

Five years ago I started exploring different mapping technologies by detailing instructions on installing Mapnik and mod_tile. Times have changed significantly in the last five years, and thanks a lot to the products offered by MapBox. After playing with TileMill, MBTiles, Leaflet and UTFGrids, it is great how many annoyances have been fixed by MapBox. I find it enjoyable making maps now, as I no longer need to worry about patching code just to get it to run, or mucking about with oddities in web browser.

Each night this week I have created a new map using Mesh Block spatial data from the Australian Bureau of Statistics (Mesh Blocks are the smallest area used when conducting surveys). I am thankful to live in a country that provides a certain amount of open data, and the ABS should be applauded for the amount of data they provide. They provide spatial data about Mesh Blocks, as well as population counts for this spatial data. It is relatively easy to merge the two and then visualise them using TileMill.

First up - population density of Sydney, i.e. persons reported to be living in each mesh block. Darker red indicates a higher population count.

View Full Screen

I find it interesting to see how many people live in certain Mesh Blocks. You will notice that Mesh Blocks with high population levels tend to be nearer public transport - either major roads with frequent bus service, or train stations.

We can look at the urban densities by determining dwellings per hectare, and do this per Mesh Block. The definition I used for urban densities comes from Ann Forsyth in "Measuring Density: Working Definitions for Residential Density and Building Intensity" (pdf). Ann discusses the need to consider net or gross densities, depending on the type of land use. At the Mesh Block level the land use type appears to be singular: Industrial, Parkland, Commercial, Residential, and Transport. Because the land use type was generally singular I have not adjusted to gross/net, but still used Ann's definitions of certain density bands:
  • Very low density: 11 dw/ha
  • Low density: 11-22 dw/ha
  • Medium density: 23-45 dw/ha
  • High density: 45 dw/ha
"dw/ha" is dwellings per hectare. I decided to map the four density levels, which can be relatively easily achieved using TileMill. See below for an example.

View Full Screen

You can zoom in and scroll over any Mesh Block in Sydney to find out more. Additional installation information on how I did this can be found on this special page: Mapping Mesh Block Data.