Street-network Sprawl in Changshun, 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.

Changshun: city in Nei Mongol, 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 Changshun, China on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Changshun as of 2014, the overall level of street-network sprawl is 2.75, 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 1.94, 2.85, 3.33 and 2.15. Street construction in Changshun increased in disconnectivity initially but has since improved. The streets constructed in 1991-2000 were the most disconnected.

Quantity of street network construction: The street network in Changshun spans a total of 74 kilometers. The period with the greatest volume of street construction was 2001-2014. These roads have an SNDi of 2.15, 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, 2.76, 2.93 and 2.75. The aggregate street network in Changshun increased in disconnectivity initially,but the trend has turned around after 2000.

Changshun and Nei Mongol do not follow the same trend in the disconnectivity of their street network constructions. The SNDi in Changshun peaked in 1991-2000, while the SNDi of street constructions in Nei Mongol followed a zig-zag trend with an overall decrease.

How do development practices in Changshun fare in comparison to others in Nei Mongol? Most recently in 2001-2014, street construction in Changshun was the 28th-most disconnected out of the 45 cities in Nei Mongol. Its position in the ranks since 1975 has fallen; relative to other cities in Nei Mongol, street construction in Changshun has become more connected. Changshun ranked 17th in 1975, 18th in 1976-1990, 15th in 1991-2000 and 28th in 2001-2014.

Changshun and China do not follow the same trend in the disconnectivity of their street network constructions. The SNDi in Changshun peaked in 1991-2000, while the SNDi of street constructions in China followed a zig-zag trend with an overall decrease.

How do development practices in Changshun fare in comparison to others in China? Most recently in 2001-2014, street construction in Changshun was the 628th-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 Changshun has become more connected. Changshun ranked 518th in 1975, 351st in 1976-1990, 191st in 1991-2000 and 628th in 2001-2014.

Changshun and Nei Mongol do not follow the same trend in the disconnectivity of their aggregate street networks. The SNDi in Changshun peaked in 1991-2000, while the SNDi of street constructions in Nei Mongol fell steadily.

To date, Changshun is the 17th-most disconnected out of the 45 cities in Nei Mongol. Its position in the ranks since 1975 has not changed. Changshun ranked 17th in 1975, 18th in 1976-1990, 16th in 1991-2000 and 17th in 2001-2014.

Changshun and China do not follow the same trend in the disconnectivity of their aggregate street networks. The SNDi in Changshun peaked in 1991-2000, while the SNDi of street constructions in China peaked in 1976-1990.

To date, Changshun is the 390th-most disconnected out of the 1651 cities in China. Its position in the ranks since 1975 has risen; relative to other cities in China, the street network in Changshun has become more disconnected. Changshun ranked 518th in 1975, 361st in 1976-1990, 293rd in 1991-2000 and 390th in 2001-2014.

As of 2015, Changshun had a built-up area of 4.41 square kilometers, and a population of 62126 people.

These are some other cities with approximately the same population: