Street-network Sprawl in Kumbo, Cameroon

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.

Kumbo: city in Nord-Ouest, Cameroon

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 Kumbo, Cameroon on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Kumbo as of 2014, the overall level of street-network sprawl is 2.57, which is in the 40th to 60th percentile of disconnectedness.

Trends in street network construction: The SNDis of street construction for the respective time periods are 2.16, 2.7, 2.41 and 3.33. Disconnectivity in street construction in Kumbo follows a zig-zag trend. In 1975, street construction was most disconnected, while construction was most connected in 2001-2014.

Quantity of street network construction: The street network in Kumbo spans a total of 171 kilometers. It is dominated by roads constructed in 1976-1990. These roads have an SNDi of 2.7, which is in the 40th to 60th percentile of disconnectedness.

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 2.16, 2.54, 2.53 and 2.57. Disconnectivity in Kumbo's street network follows a zig-zag trend. In 1975, the city was most disconnected; while it was most connected in 2001-2014.

Kumbo and Nord-Ouest do not follow the same trend in the disconnectivity of their street network constructions. The SNDi in Kumbo followed a zig-zag trend with an overall increase, while the SNDi of street constructions in Nord-Ouest rose steadily.

How do development practices in Kumbo fare in comparison to others in Nord-Ouest? Most recently in 2001-2014, street construction in Kumbo was the 3rd-most disconnected out of the 5 cities in Nord-Ouest. Its position in the ranks since 1975 has not changed. Kumbo ranked 3rd in 1975, 5th in 1976-1990, 4th in 1991-2000 and 3rd in 2001-2014.

Kumbo and Cameroon do not follow the same trend in the disconnectivity of their street network constructions. The SNDi in Kumbo followed a zig-zag trend with an overall increase, while the SNDi of street constructions in Cameroon rose steadily.

How do development practices in Kumbo fare in comparison to others in Cameroon? Most recently in 2001-2014, street construction in Kumbo was the 21st-most disconnected out of the 51 cities in Cameroon. Its position in the ranks since 1975 has fallen; relative to other cities in Cameroon, street construction in Kumbo has become more connected. Kumbo ranked 16th in 1975, 20th in 1976-1990, 27th in 1991-2000 and 21st in 2001-2014.

Kumbo and Nord-Ouest do not follow the same trend in the disconnectivity of their aggregate street networks. The SNDi in Kumbo followed a zig-zag trend with an overall increase, while the SNDi of street constructions in Nord-Ouest rose steadily.

To date, Kumbo is the 5th-most disconnected out of the 5 cities in Nord-Ouest. Its position in the ranks since 1975 has fallen; relative to other cities in Nord-Ouest, the street network in Kumbo has become more connected. Kumbo ranked 3rd in 1975, 5th in 1976-1990, 5th in 1991-2000 and 5th in 2001-2014.

Kumbo and Cameroon do not follow the same trend in the disconnectivity of their aggregate street networks. The SNDi in Kumbo followed a zig-zag trend with an overall increase, while the SNDi of street constructions in Cameroon rose steadily.

To date, Kumbo is the 25th-most disconnected out of the 51 cities in Cameroon. Its position in the ranks since 1975 has fallen; relative to other cities in Cameroon, the street network in Kumbo has become more connected. Kumbo ranked 16th in 1975, 20th in 1976-1990, 23rd in 1991-2000 and 25th in 2001-2014.

As of 2015, Kumbo had a built-up area of 2.93 square kilometers, and a population of 142999 people.

These are some other cities with approximately the same population: