Street-network Sprawl in Xuyi, 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.

Xuyi: city in Jiangsu, 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 Xuyi, China on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Xuyi as of 2014, the overall level of street-network sprawl is 1.15, which is relatively well-connected.

Trends in street network construction: The SNDis of street construction for the respective time periods are 1.88, 2.69, 0.96 and 0.83. Street construction in Xuyi 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 Xuyi spans a total of 199 kilometers. It is dominated by roads constructed in 2001-2014. These roads have an SNDi of 0.83, 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 1.88, 2.61, 1.67 and 1.15. The aggregate street network in Xuyi increased in disconnectivity initially,but the trend has turned around after 1990.

Xuyi and Jiangsu do not follow the same trend in the disconnectivity of their street network constructions. The SNDi in Xuyi peaked in 1976-1990, while the SNDi of street constructions in Jiangsu followed a zig-zag trend with an overall increase.

How do development practices in Xuyi fare in comparison to others in Jiangsu? Most recently in 2001-2014, street construction in Xuyi was the 77th-most disconnected out of the 87 cities in Jiangsu. Its position in the ranks since 1975 has fallen; relative to other cities in Jiangsu, street construction in Xuyi has become more connected. Xuyi ranked 30th in 1975, 22nd in 1976-1990, 59th in 1991-2000 and 77th in 2001-2014.

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

How do development practices in Xuyi fare in comparison to others in China? Most recently in 2001-2014, street construction in Xuyi was the 1066th-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 Xuyi has become more connected. Xuyi ranked 532nd in 1975, 399th in 1976-1990, 810th in 1991-2000 and 1066th in 2001-2014.

Xuyi and Jiangsu follow the same trend in the disconnectivity of their aggregate street networks. The SNDi for both of these peaked in 1976-1990.

To date, Xuyi is the 65th-most disconnected out of the 87 cities in Jiangsu. Its position in the ranks since 1975 has fallen; relative to other cities in Jiangsu, the street network in Xuyi has become more connected. Xuyi ranked 30th in 1975, 19th in 1976-1990, 41st in 1991-2000 and 65th in 2001-2014.

Xuyi and China follow the same trend in the disconnectivity of their aggregate street networks. The SNDi for both of these peaked in 1976-1990.

To date, Xuyi is the 1143rd-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 Xuyi has become more connected. Xuyi ranked 532nd in 1975, 393rd in 1976-1990, 811th in 1991-2000 and 1143rd in 2001-2014.

As of 2015, Xuyi had a built-up area of 22.65 square kilometers, and a population of 112430 people.

These are some other cities with approximately the same population: