Street-network Sprawl in Caijiapo, 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.

Caijiapo: city in Shaanxi, 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 Caijiapo, China on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Caijiapo as of 2014, the overall level of street-network sprawl is 3.04, 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 3.79, 2.49, 4.17 and 3.14. Disconnectivity in street construction in Caijiapo 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 Caijiapo spans a total of 117 kilometers. It is dominated by roads constructed in 1976-1990. These roads have an SNDi of 2.49, which is in the 40th to 60th percentile of disconnectedness.

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 3.79, 2.96, 3.01 and 3.04. The SNDi of the aggregate street network in fell at first, but Caijiapo has worsened in disconnectivity since 1990.

Caijiapo and Shaanxi do not follow the same trend in the disconnectivity of their street network constructions. The SNDi in Caijiapo followed a zig-zag trend with an overall decrease, while the SNDi of street constructions in Shaanxi was at its lowest in 1976-1990.

How do development practices in Caijiapo fare in comparison to others in Shaanxi? Most recently in 2001-2014, street construction in Caijiapo was the 12th-most disconnected out of the 60 cities in Shaanxi. Its position in the ranks since 1975 has fallen; relative to other cities in Shaanxi, street construction in Caijiapo has become more connected. Caijiapo ranked 4th in 1975, 15th in 1976-1990, 5th in 1991-2000 and 12th in 2001-2014.

Caijiapo and China do not follow the same trend in the disconnectivity of their street network constructions. The SNDi in Caijiapo 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 Caijiapo fare in comparison to others in China? Most recently in 2001-2014, street construction in Caijiapo was the 351st-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 Caijiapo has become more connected. Caijiapo ranked 125th in 1975, 460th in 1976-1990, 107th in 1991-2000 and 351st in 2001-2014.

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

To date, Caijiapo is the 5th-most disconnected out of the 60 cities in Shaanxi. Its position in the ranks since 1975 has fallen; relative to other cities in Shaanxi, the street network in Caijiapo has become more connected. Caijiapo ranked 4th in 1975, 9th in 1976-1990, 7th in 1991-2000 and 5th in 2001-2014.

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

To date, Caijiapo is the 276th-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 Caijiapo has become more connected. Caijiapo ranked 125th in 1975, 295th in 1976-1990, 267th in 1991-2000 and 276th in 2001-2014.

As of 2015, Caijiapo had a built-up area of 8.3 square kilometers, and a population of 78193 people.

These are some other cities with approximately the same population: