Street-network Sprawl in Wonsan, 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.

Wonsan: city in Kangwŏn-do, 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 Wonsan, North Korea on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Wonsan as of 2014, the overall level of street-network sprawl is 6.41, which is highly disconnected.

Trends in street network construction: The SNDis of street construction for the respective time periods are 6.08, 10.49, nan and 10.14. Data was not available in 1991-2000.

Quantity of street network construction: The street network in Wonsan spans a total of 149 kilometers. It is dominated by roads constructed prior to 1975. These roads have an SNDi of 6.08, 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 6.08, 6.32, 6.32 and 6.41. Overall, the SNDi of the aggregate street network has risen: the street network in Wonsan has become more disconnected. This increase has slowed: between 1975 and 1976-1990, SNDi rose by 0.24 points, but between 1991-2000 and 2001-2014, it rose by just 0.09.

Wonsan and Kangwŏn-do 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 Kangwŏn-do peaked in 1976-1990.

How do development practices in Wonsan fare in comparison to others in Kangwŏn-do? Most recently in 2001-2014, street construction in Wonsan was the 1st-most disconnected out of the 5 cities in Kangwŏn-do. Its position in the ranks since 1975 has fallen; relative to other cities in Kangwŏn-do, street construction in Wonsan has become more connected. Wonsan ranked 1st in 1975, 2nd in 1976-1990 and 1st in 2001-2014. There was no ranking in 1991-2000 due to unavailable data.

Wonsan 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 Wonsan fare in comparison to others in North Korea? Most recently in 2001-2014, street construction in Wonsan was the 2nd-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, street construction in Wonsan has become more disconnected. Wonsan ranked 13th in 1975, 4th in 1976-1990 and 2nd in 2001-2014. There was no ranking in 1991-2000 due to unavailable data.

Wonsan and Kangwŏn-do do not follow the same trend in the disconnectivity of their aggregate street networks. The SNDi in Wonsan rose steadily, while the SNDi of street constructions in Kangwŏn-do rose steadily.

To date, Wonsan is the 1st-most disconnected out of the 5 cities in Kangwŏn-do. Its position in the ranks since 1975 has not changed. Wonsan ranked 1st in 1975, 1st in 1976-1990, 1st in 1991-2000 and 1st in 2001-2014.

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

To date, Wonsan is the 9th-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 Wonsan has become more disconnected. Wonsan ranked 13th in 1975, 11th in 1976-1990, 11th in 1991-2000 and 9th in 2001-2014.

As of 2015, Wonsan had a built-up area of 4.24 square kilometers, and a population of 326575 people.

These are some other cities with approximately the same population: