Street-network Sprawl in Gwolong, Nigeria

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.

Gwolong: city in Plateau, Nigeria

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 Gwolong, Nigeria on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Gwolong as of 2014, the overall level of street-network sprawl is 0.73, which is relatively well-connected.

Trends in street network construction: The SNDis of street construction for the respective time periods are -1.95, -0.22, nan and 6.04. Data was not available in 1991-2000.

Quantity of street network construction: The street network in Gwolong spans a total of 21 kilometers. It is dominated by roads constructed in 1976-1990. These roads have an SNDi of -0.22, which is very 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 -1.95, -0.32, -0.32 and 0.73. Overall, the SNDi of the aggregate street network has risen: the street network in Gwolong has become more disconnected. This increase has slowed: between 1975 and 1976-1990, SNDi rose by 1.64 points, but between 1991-2000 and 2001-2014, it rose by just 1.05.

Gwolong and Plateau 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 Plateau rose steadily.

How do development practices in Gwolong fare in comparison to others in Plateau? Most recently in 2001-2014, street construction in Gwolong was the 2nd-most disconnected out of the 10 cities in Plateau. Its position in the ranks since 1975 has fallen; relative to other cities in Plateau, street construction in Gwolong has become more connected. Gwolong ranked 5th in 1975, 6th in 1976-1990 and 2nd in 2001-2014. There was no ranking in 1991-2000 due to unavailable data.

Gwolong and Nigeria 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 Nigeria peaked in 1991-2000.

How do development practices in Gwolong fare in comparison to others in Nigeria? Most recently in 2001-2014, street construction in Gwolong was the 35th-most disconnected out of the 411 cities in Nigeria. Its position in the ranks since 1975 has fallen; relative to other cities in Nigeria, street construction in Gwolong has become more connected. Gwolong ranked 242nd in 1975, 306th in 1976-1990 and 35th in 2001-2014. There was no ranking in 1991-2000 due to unavailable data.

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

To date, Gwolong is the 6th-most disconnected out of the 10 cities in Plateau. Its position in the ranks since 1975 has fallen; relative to other cities in Plateau, the street network in Gwolong has become more connected. Gwolong ranked 5th in 1975, 9th in 1976-1990, 8th in 1991-2000 and 6th in 2001-2014.

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

To date, Gwolong is the 295th-most disconnected out of the 411 cities in Nigeria. Its position in the ranks since 1975 has fallen; relative to other cities in Nigeria, the street network in Gwolong has become more connected. Gwolong ranked 242nd in 1975, 322nd in 1976-1990, 340th in 1991-2000 and 295th in 2001-2014.

As of 2015, Gwolong had a built-up area of 1.06 square kilometers, and a population of 51675 people.

These are some other cities with approximately the same population: