Street-network Sprawl in Jixian, 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.

Jixian: city in Heilongjiang, 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 Jixian, China on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Jixian as of 2014, the overall level of street-network sprawl is 2.76, 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 2.66, 2.3, 1.21 and 4.05. The disconnectivity of new streets constructed in Jixian fell, then rose. In 1991-2000, new street layouts were the most connected.

Quantity of street network construction: The street network in Jixian spans a total of 154 kilometers. It is dominated by roads constructed prior to 1975. These roads have an SNDi of 2.66, 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 2.66, 2.57, 2.52 and 2.76. The SNDi of the aggregate street network in fell at first, but Jixian has worsened in disconnectivity since 2000.

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

How do development practices in Jixian fare in comparison to others in Heilongjiang? Most recently in 2001-2014, street construction in Jixian was the 12th-most disconnected out of the 52 cities in Heilongjiang. Its position in the ranks since 1975 has not changed. Jixian ranked 12th in 1975, 22nd in 1976-1990, 17th in 1991-2000 and 12th in 2001-2014.

Jixian and China do not follow the same trend in the disconnectivity of their street network constructions. The SNDi in Jixian was at its lowest 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 Jixian fare in comparison to others in China? Most recently in 2001-2014, street construction in Jixian was the 192nd-most disconnected out of the 1651 cities in China. Its position in the ranks since 1975 has risen; relative to other cities in China, street construction in Jixian has become more disconnected. Jixian ranked 315th in 1975, 529th in 1976-1990, 715th in 1991-2000 and 192nd in 2001-2014.

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

To date, Jixian is the 14th-most disconnected out of the 52 cities in Heilongjiang. Its position in the ranks since 1975 has fallen; relative to other cities in Heilongjiang, the street network in Jixian has become more connected. Jixian ranked 12th in 1975, 15th in 1976-1990, 16th in 1991-2000 and 14th in 2001-2014.

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

To date, Jixian is the 383rd-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 Jixian has become more connected. Jixian ranked 315th in 1975, 414th in 1976-1990, 433rd in 1991-2000 and 383rd in 2001-2014.

As of 2015, Jixian had a built-up area of 13.29 square kilometers, and a population of 67360 people.

These are some other cities with approximately the same population: