Street-network Sprawl in Bagwai, 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.

Bagwai: city in Kano, 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 Bagwai, Nigeria on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Bagwai as of 2014, the overall level of street-network sprawl is -0.9, which is very well-connected.

Trends in street network construction: The SNDis of street construction for the respective time periods are -0.76, -0.84, nan and nan. Data was not available in 1991-2000 and 2001-2014.

Quantity of street network construction: The street network in Bagwai spans a total of 37 kilometers. It is dominated by roads constructed in 1976-1990. These roads have an SNDi of -0.84, 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 -0.76, -0.93, -0.96 and -0.9. The SNDi of the aggregate street network in fell at first, but Bagwai has worsened in disconnectivity since 2000.

Bagwai and Kano 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 Kano peaked in 1976-1990.

How do development practices in Bagwai fare in comparison to others in Kano? out of the 22 cities in Kano. Its position in the ranks since 1975 has not changed. Bagwai ranked 17th in 1975 and 17th in 1976-1990. There was no ranking in 1991-2000 and 2001-2014 due to unavailable data.

Bagwai 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 Bagwai fare in comparison to others in Nigeria? 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 Bagwai has become more connected. Bagwai ranked 232nd in 1975 and 350th in 1976-1990. There was no ranking in 1991-2000 and 2001-2014 due to unavailable data.

Bagwai and Kano do not follow the same trend in the disconnectivity of their aggregate street networks. The SNDi in Bagwai was at its lowest in 1991-2000, while the SNDi of street constructions in Kano rose steadily.

To date, Bagwai is the 22nd-most disconnected out of the 22 cities in Kano. Its position in the ranks since 1975 has fallen; relative to other cities in Kano, the street network in Bagwai has become more connected. Bagwai ranked 17th in 1975, 20th in 1976-1990, 21st in 1991-2000 and 22nd in 2001-2014.

Bagwai and Nigeria do not follow the same trend in the disconnectivity of their aggregate street networks. The SNDi in Bagwai was at its lowest in 1991-2000, while the SNDi of street constructions in Nigeria rose steadily.

To date, Bagwai is the 395th-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 Bagwai has become more connected. Bagwai ranked 232nd in 1975, 370th in 1976-1990, 379th in 1991-2000 and 395th in 2001-2014.

As of 2015, Bagwai had a built-up area of 0.83 square kilometers, and a population of 60529 people.

These are some other cities with approximately the same population: