Street-network Sprawl in Shenmu, 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.

Shenmu: 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 Shenmu, China on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Shenmu as of 2014, the overall level of street-network sprawl is 0.88, which is relatively well-connected.

Trends in street network construction: The SNDis of street construction for the respective time periods are -0.62, 0.45, 2.09 and 0.92. Street construction in Shenmu increased in disconnectivity initially but has since improved. The streets constructed in 1991-2000 were the most disconnected.

Quantity of street network construction: The street network in Shenmu spans a total of 147 kilometers. The period with the greatest volume of street construction was 1976-1990. These roads have an SNDi of 0.45, 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 -0.62, 0.43, 0.88 and 0.88. Overall, the SNDi of the aggregate street network has risen: the street network in Shenmu has become more disconnected. This increase has slowed: between 1975 and 1976-1990, SNDi rose by 1.05 points, but between 1991-2000 and 2001-2014, it rose by just 0.0.

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

How do development practices in Shenmu fare in comparison to others in Shaanxi? Most recently in 2001-2014, street construction in Shenmu was the 38th-most disconnected out of the 60 cities in Shaanxi. Its position in the ranks since 1975 has risen; relative to other cities in Shaanxi, street construction in Shenmu has become more disconnected. Shenmu ranked 47th in 1975, 41st in 1976-1990, 15th in 1991-2000 and 38th in 2001-2014.

Shenmu and China do not follow the same trend in the disconnectivity of their street network constructions. The SNDi in Shenmu peaked 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 Shenmu fare in comparison to others in China? Most recently in 2001-2014, street construction in Shenmu was the 1034th-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 Shenmu has become more disconnected. Shenmu ranked 1226th in 1975, 1246th in 1976-1990, 459th in 1991-2000 and 1034th in 2001-2014.

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

To date, Shenmu is the 48th-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 Shenmu has become more connected. Shenmu ranked 47th in 1975, 46th in 1976-1990, 44th in 1991-2000 and 48th in 2001-2014.

Shenmu and China do not follow the same trend in the disconnectivity of their aggregate street networks. The SNDi in Shenmu rose steadily, while the SNDi of street constructions in China peaked in 1976-1990.

To date, Shenmu is the 1279th-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 Shenmu has become more connected. Shenmu ranked 1226th in 1975, 1365th in 1976-1990, 1204th in 1991-2000 and 1279th in 2001-2014.

As of 2015, Shenmu had a built-up area of 10.66 square kilometers, and a population of 190103 people.

These are some other cities with approximately the same population: