Street-network Sprawl in Quxian, China

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.

Quxian: city in Sichuan, China

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 Quxian, China on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Quxian as of 2014, the overall level of street-network sprawl is 2.68, which is in the 40th to 60th percentile of disconnectedness.

Trends in street network construction: The SNDis of street construction for the respective time periods are 3.49, 2.2, 4.52 and 2.26. Disconnectivity in street construction in Quxian follows a zig-zag trend. In 1976-1990, street construction was most disconnected, while construction was most connected in 1991-2000.

Quantity of street network construction: The street network in Quxian spans a total of 119 kilometers. The period with the greatest volume of street construction was 1976-1990. These roads have an SNDi of 2.2, 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 3.49, 2.73, 2.8 and 2.68. Disconnectivity in Quxian's street network follows a zig-zag trend. In 2001-2014, the city was most disconnected; while it was most connected in 1975.

Quxian and Sichuan do not follow the same trend in the disconnectivity of their street network constructions. The SNDi in Quxian followed a zig-zag trend with an overall decrease, while the SNDi of street constructions in Sichuan was at its lowest in 1991-2000.

How do development practices in Quxian fare in comparison to others in Sichuan? Most recently in 2001-2014, street construction in Quxian was the 45th-most disconnected out of the 102 cities in Sichuan. Its position in the ranks since 1975 has fallen; relative to other cities in Sichuan, street construction in Quxian has become more connected. Quxian ranked 17th in 1975, 42nd in 1976-1990, 4th in 1991-2000 and 45th in 2001-2014.

Quxian and China do not follow the same trend in the disconnectivity of their street network constructions. The SNDi in Quxian followed a zig-zag trend with an overall decrease, while the SNDi of street constructions in China followed a zig-zag trend with an overall decrease.

How do development practices in Quxian fare in comparison to others in China? Most recently in 2001-2014, street construction in Quxian was the 580th-most disconnected out of the 1651 cities in China. Its position in the ranks since 1975 has fallen; relative to other cities in China, street construction in Quxian has become more connected. Quxian ranked 159th in 1975, 575th in 1976-1990, 84th in 1991-2000 and 580th in 2001-2014.

Quxian and Sichuan do not follow the same trend in the disconnectivity of their aggregate street networks. The SNDi in Quxian followed a zig-zag trend with an overall decrease, while the SNDi of street constructions in Sichuan was at its lowest in 1991-2000.

To date, Quxian is the 37th-most disconnected out of the 102 cities in Sichuan. Its position in the ranks since 1975 has fallen; relative to other cities in Sichuan, the street network in Quxian has become more connected. Quxian ranked 17th in 1975, 32nd in 1976-1990, 29th in 1991-2000 and 37th in 2001-2014.

Quxian and China do not follow the same trend in the disconnectivity of their aggregate street networks. The SNDi in Quxian followed a zig-zag trend with an overall decrease, while the SNDi of street constructions in China peaked in 1976-1990.

To date, Quxian is the 411th-most disconnected out of the 1651 cities in China. Its position in the ranks since 1975 has fallen; relative to other cities in China, the street network in Quxian has become more connected. Quxian ranked 159th in 1975, 367th in 1976-1990, 332nd in 1991-2000 and 411th in 2001-2014.

As of 2015, Quxian had a built-up area of 4.07 square kilometers, and a population of 171914 people.

These are some other cities with approximately the same population: