Street-network Sprawl in 沂南县, 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.

沂南县: city in Shandong, 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 沂南县, China on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in 沂南县 as of 2014, the overall level of street-network sprawl is 0.93, which is relatively well-connected.

Trends in street network construction: The SNDis of street construction for the respective time periods are 0.63, 0.33, -0.16 and 1.51. The disconnectivity of new streets constructed in 沂南县 fell, then rose. In 1991-2000, new street layouts were the most connected.

Quantity of street network construction: The street network in 沂南县 spans a total of 212 kilometers. It is dominated by roads constructed in 2001-2014. These roads have an SNDi of 1.51, 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 0.63, 0.39, 0.18 and 0.93. The SNDi of the aggregate street network in fell at first, but 沂南县 has worsened in disconnectivity since 2000.

沂南县 and Shandong do not follow the same trend in the disconnectivity of their street network constructions. The SNDi in 沂南县 was at its lowest in 1991-2000, while the SNDi of street constructions in Shandong followed a zig-zag trend with an overall increase.

How do development practices in 沂南县 fare in comparison to others in Shandong? Most recently in 2001-2014, street construction in 沂南县 was the 41st-most disconnected out of the 113 cities in Shandong. Its position in the ranks since 1975 has risen; relative to other cities in Shandong, street construction in 沂南县 has become more disconnected. 沂南县 ranked 45th in 1975, 76th in 1976-1990, 88th in 1991-2000 and 41st in 2001-2014.

沂南县 and China do not follow the same trend in the disconnectivity of their street network constructions. The SNDi in 沂南县 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 沂南县 fare in comparison to others in China? Most recently in 2001-2014, street construction in 沂南县 was the 853rd-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 沂南县 has become more disconnected. 沂南县 ranked 943rd in 1975, 1282nd in 1976-1990, 1119th in 1991-2000 and 853rd in 2001-2014.

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

To date, 沂南县 is the 55th-most disconnected out of the 113 cities in Shandong. Its position in the ranks since 1975 has fallen; relative to other cities in Shandong, the street network in 沂南县 has become more connected. 沂南县 ranked 45th in 1975, 80th in 1976-1990, 87th in 1991-2000 and 55th in 2001-2014.

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

To date, 沂南县 is the 1254th-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 沂南县 has become more connected. 沂南县 ranked 943rd in 1975, 1379th in 1976-1990, 1464th in 1991-2000 and 1254th in 2001-2014.

As of 2015, 沂南县 had a built-up area of 25.38 square kilometers, and a population of 142152 people.

These are some other cities with approximately the same population: