Street-network Sprawl in Wanqingsha, 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.

Wanqingsha: city in Guangdong, 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 Wanqingsha, China on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Wanqingsha as of 2014, the overall level of street-network sprawl is 1.99, which is relatively well-connected.

Trends in street network construction: The SNDis of street construction for the respective time periods are 3.71, 4.5, 0.73 and 1.61. Disconnectivity in street construction in Wanqingsha follows a zig-zag trend. In 1991-2000, street construction was most disconnected, while construction was most connected in 1976-1990.

Quantity of street network construction: The street network in Wanqingsha spans a total of 133 kilometers. It is dominated by roads constructed in 2001-2014. These roads have an SNDi of 1.61, 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 3.71, 4.19, 2.44 and 1.99. The aggregate street network in Wanqingsha increased in disconnectivity initially,but the trend has turned around after 1990.

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

How do development practices in Wanqingsha fare in comparison to others in Guangdong? Most recently in 2001-2014, street construction in Wanqingsha was the 62nd-most disconnected out of the 109 cities in Guangdong. Its position in the ranks since 1975 has fallen; relative to other cities in Guangdong, street construction in Wanqingsha has become more connected. Wanqingsha ranked 18th in 1975, 6th in 1976-1990, 63rd in 1991-2000 and 62nd in 2001-2014.

Wanqingsha and China follow the same trend in the disconnectivity of their street network constructions. The SNDi for both of these followed a zig-zag trend with an overall decrease.

How do development practices in Wanqingsha fare in comparison to others in China? Most recently in 2001-2014, street construction in Wanqingsha was the 814th-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 Wanqingsha has become more connected. Wanqingsha ranked 132nd in 1975, 90th in 1976-1990, 884th in 1991-2000 and 814th in 2001-2014.

Wanqingsha and Guangdong do not follow the same trend in the disconnectivity of their aggregate street networks. The SNDi in Wanqingsha peaked in 1976-1990, while the SNDi of street constructions in Guangdong was at its lowest in 1991-2000.

To date, Wanqingsha is the 55th-most disconnected out of the 109 cities in Guangdong. Its position in the ranks since 1975 has fallen; relative to other cities in Guangdong, the street network in Wanqingsha has become more connected. Wanqingsha ranked 18th in 1975, 12th in 1976-1990, 37th in 1991-2000 and 55th in 2001-2014.

Wanqingsha 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, Wanqingsha is the 706th-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 Wanqingsha has become more connected. Wanqingsha ranked 132nd in 1975, 86th in 1976-1990, 462nd in 1991-2000 and 706th in 2001-2014.

As of 2015, Wanqingsha had a built-up area of 7.4 square kilometers, and a population of 111179 people.

These are some other cities with approximately the same population: