Street-network Sprawl in 宁阳县, 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.

宁阳县: 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 宁阳县, China on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in 宁阳县 as of 2014, the overall level of street-network sprawl is 0.97, which is relatively well-connected.

Trends in street network construction: The SNDis of street construction for the respective time periods are -0.52, 2.24, 0.68 and 0.7. Disconnectivity in street construction in 宁阳县 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 宁阳县 spans a total of 165 kilometers. It is dominated by roads constructed in 2001-2014. These roads have an SNDi of 0.7, 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 -0.52, 1.43, 1.15 and 0.97. The aggregate street network in 宁阳县 increased in disconnectivity initially,but the trend has turned around after 1990.

宁阳县 and Shandong 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 宁阳县 fare in comparison to others in Shandong? Most recently in 2001-2014, street construction in 宁阳县 was the 64th-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 宁阳县 has become more disconnected. 宁阳县 ranked 75th in 1975, 12th in 1976-1990, 64th in 1991-2000 and 64th in 2001-2014.

宁阳县 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 宁阳县 fare in comparison to others in China? Most recently in 2001-2014, street construction in 宁阳县 was the 1109th-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 宁阳县 has become more disconnected. 宁阳县 ranked 1211th in 1975, 553rd in 1976-1990, 902nd in 1991-2000 and 1109th in 2001-2014.

宁阳县 and Shandong follow the same trend in the disconnectivity of their aggregate street networks. The SNDi for both of these peaked in 1976-1990.

To date, 宁阳县 is the 52nd-most disconnected out of the 113 cities in Shandong. Its position in the ranks since 1975 has risen; relative to other cities in Shandong, the street network in 宁阳县 has become more disconnected. 宁阳县 ranked 75th in 1975, 37th in 1976-1990, 44th in 1991-2000 and 52nd in 2001-2014.

宁阳县 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, 宁阳县 is the 1232nd-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 宁阳县 has become more connected. 宁阳县 ranked 1211th in 1975, 914th in 1976-1990, 1083rd in 1991-2000 and 1232nd in 2001-2014.

As of 2015, 宁阳县 had a built-up area of 12.53 square kilometers, and a population of 123471 people.

These are some other cities with approximately the same population: