Street-network Sprawl in Toronto, Canada


What is Street-network sprawl?

Street-network Sprawl is a way to measure urban sprawl, worldwide, through the connectedness of the streets. Less sprawl means more connected, more walkable streets. Well-connected streets – like New York City’s grid – are more walkable and can be served by public transit.

The street network is permanent, and its connectivity affects the livability and environmental footprint of cities for decades and centuries to come. In places with more connected streets, residents drive less and walk more. A well-connected street network is associated with better outcomes for health, the environment, sustainable consumption, social integration, and equity.

We can quantify how connected street networks are with the Street Network Disconnectedness Index (SNDi).

SNDi -- our measure of street-network sprawl (disconnectedness)

The SNDi is a comprehensive measurement of “sprawl”. It captures:

A higher SNDi means less-connected streets – i.e., more sprawl. For the 10137 cities in our dataset, the average SNDi is 2.25, with half of the cities' SNDis falling between 1.08 and 3.25.

More information on the sprawl index can be found in these research papers:

To see the state of street-network sprawl across the globe, visit the sprawlmap.

Toronto: city in Ontario, Canada

What exactly constitutes the spatial extent of the city? For these aggregations, we used the Global Human Settlement Layer Urban Center Database (GHS-UCDB) to define the boundaries of the city. These cities -- or urban centers -- cover areas that are densely populated and built-up, and so may extend beyond the spatial borders of these cities that we may be familiar with. The GHS area is shaded in blue.

View Toronto, Canada on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Toronto as of 2014, the overall level of street-network sprawl is 2.21, which is relatively well-connected.

Trends in street network construction: The SNDis of street construction for the respective time periods are 1.94, 2.74, 2.55 and 2.23. Street construction in Toronto increased in disconnectivity initially but has since improved. The streets constructed in 1976-1990 were the most disconnected.

Quantity of street network construction: The street network in Toronto spans a total of 18345 kilometers. It is dominated by roads constructed prior to 1975. These roads have an SNDi of 1.94, which is relatively well-connected.

Effect on the aggregate network: New construction in each period adds to the total stock of streets, but does not change streets that have already been built. Therefore, it has a limited effect on the street network as a whole. The SNDis of the aggregate street network in the respective time periods are 1.94, 2.17, 2.21 and 2.21. The aggregate street network in Toronto increased in disconnectivity initially,but the trend has turned around after 2000.

Toronto and Ontario do not follow the same trend in the disconnectivity of their street network constructions. The SNDi in Toronto peaked in 1976-1990, while the SNDi of street constructions in Ontario peaked in 1991-2000.

How do development practices in Toronto fare in comparison to others in Ontario? Most recently in 2001-2014, street construction in Toronto was the 13th-most disconnected out of the 20 cities in Ontario. Its position in the ranks since 1975 has fallen; relative to other cities in Ontario, street construction in Toronto has become more connected. Toronto ranked 8th in 1975, 12th in 1976-1990, 15th in 1991-2000 and 13th in 2001-2014.

Toronto and Canada do not follow the same trend in the disconnectivity of their street network constructions. The SNDi in Toronto peaked in 1976-1990, while the SNDi of street constructions in Canada rose steadily.

How do development practices in Toronto fare in comparison to others in Canada? Most recently in 2001-2014, street construction in Toronto was the 39th-most disconnected out of the 48 cities in Canada. Its position in the ranks since 1975 has fallen; relative to other cities in Canada, street construction in Toronto has become more connected. Toronto ranked 20th in 1975, 32nd in 1976-1990, 41st in 1991-2000 and 39th in 2001-2014.

Toronto and Ontario do not follow the same trend in the disconnectivity of their aggregate street networks. The SNDi in Toronto peaked in 1991-2000, while the SNDi of street constructions in Ontario rose steadily.

To date, Toronto is the 7th-most disconnected out of the 20 cities in Ontario. Its position in the ranks since 1975 has risen; relative to other cities in Ontario, the street network in Toronto has become more disconnected. Toronto ranked 8th in 1975, 8th in 1976-1990, 7th in 1991-2000 and 7th in 2001-2014.

Toronto and Canada do not follow the same trend in the disconnectivity of their aggregate street networks. The SNDi in Toronto peaked in 1991-2000, while the SNDi of street constructions in Canada rose steadily.

To date, Toronto is the 23rd-most disconnected out of the 48 cities in Canada. Its position in the ranks since 1975 has fallen; relative to other cities in Canada, the street network in Toronto has become more connected. Toronto ranked 20th in 1975, 22nd in 1976-1990, 22nd in 1991-2000 and 23rd in 2001-2014.

As of 2015, Toronto had a built-up area of 1471.82 square kilometers, and a population of 6036145 people.

These are some other cities with approximately the same population: