Street-network Sprawl in Kwail, North Korea

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.

Kwail: city in Hwanghae-namdo, North Korea

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 Kwail, North Korea on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Kwail as of 2014, the overall level of street-network sprawl is 6.52, which is highly disconnected.

Trends in street network construction: The SNDis of street construction for the respective time periods are 6.57, 6.73, nan and nan. Data was not available in 1991-2000 and 2001-2014.

Quantity of street network construction: The street network in Kwail spans a total of 43 kilometers. It is dominated by roads constructed prior to 1975. These roads have an SNDi of 6.57, 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 6.57, 6.68, 6.76 and 6.52. The aggregate street network in Kwail increased in disconnectivity initially,but the trend has turned around after 2000.

Kwail and Hwanghae-namdo 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 Hwanghae-namdo followed a zig-zag trend with an overall increase.

How do development practices in Kwail fare in comparison to others in Hwanghae-namdo? out of the 11 cities in Hwanghae-namdo. Its position in the ranks since 1975 has fallen; relative to other cities in Hwanghae-namdo, street construction in Kwail has become more connected. Kwail ranked 1st in 1975 and 3rd in 1976-1990. There was no ranking in 1991-2000 and 2001-2014 due to unavailable data.

Kwail and North Korea 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 North Korea followed a zig-zag trend with an overall increase.

How do development practices in Kwail fare in comparison to others in North Korea? out of the 79 cities in North Korea. Its position in the ranks since 1975 has fallen; relative to other cities in North Korea, street construction in Kwail has become more connected. Kwail ranked 7th in 1975 and 17th in 1976-1990. There was no ranking in 1991-2000 and 2001-2014 due to unavailable data.

Kwail and Hwanghae-namdo do not follow the same trend in the disconnectivity of their aggregate street networks. The SNDi in Kwail peaked in 1991-2000, while the SNDi of street constructions in Hwanghae-namdo rose steadily.

To date, Kwail is the 1st-most disconnected out of the 11 cities in Hwanghae-namdo. Its position in the ranks since 1975 has not changed. Kwail ranked 1st in 1975, 1st in 1976-1990, 1st in 1991-2000 and 1st in 2001-2014.

Kwail and North Korea do not follow the same trend in the disconnectivity of their aggregate street networks. The SNDi in Kwail peaked in 1991-2000, while the SNDi of street constructions in North Korea rose steadily.

To date, Kwail is the 6th-most disconnected out of the 79 cities in North Korea. Its position in the ranks since 1975 has risen; relative to other cities in North Korea, the street network in Kwail has become more disconnected. Kwail ranked 7th in 1975, 5th in 1976-1990, 5th in 1991-2000 and 6th in 2001-2014.

As of 2015, Kwail had a built-up area of 0.85 square kilometers, and a population of 52077 people.

These are some other cities with approximately the same population: