Street-network Sprawl in Jiangxia, 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.

Jiangxia: city in Hubei, 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 Jiangxia, China on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Jiangxia as of 2014, the overall level of street-network sprawl is 1.73, which is relatively well-connected.

Trends in street network construction: The SNDis of street construction for the respective time periods are -0.15, 1.92, 2.24 and 0.06. Street construction in Jiangxia 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 Jiangxia spans a total of 136 kilometers. It is dominated by roads constructed in 1991-2000. These roads have an SNDi of 2.24, 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 -0.15, 1.86, 1.94 and 1.73. The aggregate street network in Jiangxia increased in disconnectivity initially,but the trend has turned around after 2000.

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

How do development practices in Jiangxia fare in comparison to others in Hubei? Most recently in 2001-2014, street construction in Jiangxia was the 65th-most disconnected out of the 80 cities in Hubei. Its position in the ranks since 1975 has fallen; relative to other cities in Hubei, street construction in Jiangxia has become more connected. Jiangxia ranked 57th in 1975, 36th in 1976-1990, 29th in 1991-2000 and 65th in 2001-2014.

Jiangxia and China do not follow the same trend in the disconnectivity of their street network constructions. The SNDi in Jiangxia 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 Jiangxia fare in comparison to others in China? Most recently in 2001-2014, street construction in Jiangxia was the 1280th-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 Jiangxia has become more connected. Jiangxia ranked 1149th in 1975, 688th in 1976-1990, 417th in 1991-2000 and 1280th in 2001-2014.

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

To date, Jiangxia is the 44th-most disconnected out of the 80 cities in Hubei. Its position in the ranks since 1975 has risen; relative to other cities in Hubei, the street network in Jiangxia has become more disconnected. Jiangxia ranked 57th in 1975, 36th in 1976-1990, 40th in 1991-2000 and 44th in 2001-2014.

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

To date, Jiangxia is the 840th-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 Jiangxia has become more disconnected. Jiangxia ranked 1149th in 1975, 721st in 1976-1990, 688th in 1991-2000 and 840th in 2001-2014.

As of 2015, Jiangxia had a built-up area of 9.67 square kilometers, and a population of 275484 people.

These are some other cities with approximately the same population: