Street-network Sprawl in Tuquan, 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.

Tuquan: city in Nei Mongol, 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 Tuquan, China on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Tuquan as of 2014, the overall level of street-network sprawl is 0.37, which is very well-connected.

Trends in street network construction: The SNDis of street construction for the respective time periods are -1.21, 1.24, -1.12 and 0.3. Disconnectivity in street construction in Tuquan follows a zig-zag trend. In 1975, street construction was most disconnected, while construction was most connected in 1976-1990.

Quantity of street network construction: The street network in Tuquan spans a total of 69 kilometers. It is dominated by roads constructed in 1976-1990. These roads have an SNDi of 1.24, 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 -1.21, 0.42, 0.37 and 0.37. The aggregate street network in Tuquan increased in disconnectivity initially,but the trend has turned around after 1990.

Tuquan and Nei Mongol do not follow the same trend in the disconnectivity of their street network constructions. The SNDi in Tuquan followed a zig-zag trend with an overall increase, while the SNDi of street constructions in Nei Mongol followed a zig-zag trend with an overall decrease.

How do development practices in Tuquan fare in comparison to others in Nei Mongol? Most recently in 2001-2014, street construction in Tuquan was the 43rd-most disconnected out of the 45 cities in Nei Mongol. Its position in the ranks since 1975 has fallen; relative to other cities in Nei Mongol, street construction in Tuquan has become more connected. Tuquan ranked 30th in 1975, 33rd in 1976-1990, 37th in 1991-2000 and 43rd in 2001-2014.

Tuquan 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 increase.

How do development practices in Tuquan fare in comparison to others in China? Most recently in 2001-2014, street construction in Tuquan was the 1222nd-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 Tuquan has become more disconnected. Tuquan ranked 1281st in 1975, 986th in 1976-1990, 1257th in 1991-2000 and 1222nd in 2001-2014.

Tuquan and Nei Mongol do not follow the same trend in the disconnectivity of their aggregate street networks. The SNDi in Tuquan peaked in 1976-1990, while the SNDi of street constructions in Nei Mongol fell steadily.

To date, Tuquan is the 44th-most disconnected out of the 45 cities in Nei Mongol. Its position in the ranks since 1975 has fallen; relative to other cities in Nei Mongol, the street network in Tuquan has become more connected. Tuquan ranked 30th in 1975, 38th in 1976-1990, 42nd in 1991-2000 and 44th in 2001-2014.

Tuquan 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, Tuquan is the 1459th-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 Tuquan has become more connected. Tuquan ranked 1281st in 1975, 1370th in 1976-1990, 1411th in 1991-2000 and 1459th in 2001-2014.

As of 2015, Tuquan had a built-up area of 8.68 square kilometers, and a population of 60644 people.

These are some other cities with approximately the same population: