Street-network Sprawl in Mizhi, 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.

Mizhi: 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 Mizhi, China on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Mizhi as of 2014, the overall level of street-network sprawl is 2.96, 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 nan, 3.78, 1.84 and 2.35. Data was not available in 1975.

Quantity of street network construction: The street network in Mizhi spans a total of 94 kilometers. It is dominated by roads constructed prior to 1975. These roads have an SNDi of nan, which is highly disconnected.

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 nan, 3.78, 3.32 and 2.96. Data was not available in 1975.

Mizhi and Shaanxi do not follow the same trend in the disconnectivity of their street network constructions. There was not enough data from the city, while the SNDi of street constructions in Shaanxi was at its lowest in 1976-1990.

How do development practices in Mizhi fare in comparison to others in Shaanxi? Most recently in 2001-2014, street construction in Mizhi was the 21st-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 Mizhi has become more connected. Mizhi ranked 7th in 1976-1990, 18th in 1991-2000 and 21st in 2001-2014. There was no ranking in 1975 due to unavailable data.

Mizhi and China do not follow the same trend in the disconnectivity of their street network constructions. There was not enough data from the city, while the SNDi of street constructions in China followed a zig-zag trend with an overall decrease.

How do development practices in Mizhi fare in comparison to others in China? Most recently in 2001-2014, street construction in Mizhi was the 557th-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 Mizhi has become more connected. Mizhi ranked 167th in 1976-1990, 535th in 1991-2000 and 557th in 2001-2014. There was no ranking in 1975 due to unavailable data.

Mizhi and Shaanxi do not follow the same trend in the disconnectivity of their aggregate street networks. There was not enough data from the city, while the SNDi of street constructions in Shaanxi was at its lowest in 1991-2000.

To date, Mizhi is the 6th-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 Mizhi has become more connected. Mizhi ranked 4th in 1976-1990, 5th in 1991-2000 and 6th in 2001-2014. There was no ranking in 1975 due to unavailable data.

Mizhi and China do not follow the same trend in the disconnectivity of their aggregate street networks. There was not enough data from the city, while the SNDi of street constructions in China peaked in 1976-1990.

To date, Mizhi is the 300th-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 Mizhi has become more connected. Mizhi ranked 124th in 1976-1990, 186th in 1991-2000 and 300th in 2001-2014. There was no ranking in 1975 due to unavailable data.

As of 2015, Mizhi had a built-up area of 3.95 square kilometers, and a population of 60415 people.

These are some other cities with approximately the same population: