Street-network Sprawl in Cazombo, Angola

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.

Cazombo: city in Moxico, Angola

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 Cazombo, Angola on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Cazombo as of 2014, the overall level of street-network sprawl is 2.15, which is relatively well-connected.

Trends in street network construction: The SNDis of street construction for the respective time periods are 1.15, nan, nan and 3.01. Data was not available in 1976-1990 and 1991-2000.

Quantity of street network construction: The street network in Cazombo spans a total of 49 kilometers. It is dominated by roads constructed in 2001-2014. These roads have an SNDi of 3.01, 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 1.15, 1.61, 0.71 and 2.15. Disconnectivity in Cazombo's street network follows a zig-zag trend. In 1991-2000, the city was most disconnected; while it was most connected in 2001-2014.

Cazombo and Moxico 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 Moxico peaked in 1991-2000.

How do development practices in Cazombo fare in comparison to others in Moxico? Most recently in 2001-2014, street construction in Cazombo was the 1st-most disconnected out of the 3 cities in Moxico. Cazombo ranked 2nd in 1975 and 1st in 2001-2014. There was no ranking in 1976-1990 and 1991-2000 due to unavailable data.

Cazombo and Angola 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 Angola peaked in 1976-1990.

How do development practices in Cazombo fare in comparison to others in Angola? Most recently in 2001-2014, street construction in Cazombo was the 16th-most disconnected out of the 51 cities in Angola. Cazombo ranked 20th in 1975 and 16th in 2001-2014. There was no ranking in 1976-1990 and 1991-2000 due to unavailable data.

Cazombo and Moxico do not follow the same trend in the disconnectivity of their aggregate street networks. The SNDi in Cazombo followed a zig-zag trend with an overall increase, while the SNDi of street constructions in Moxico was at its lowest in 1976-1990.

To date, Cazombo is the 1st-most disconnected out of the 3 cities in Moxico. Its position in the ranks since 1975 has risen; relative to other cities in Moxico, the street network in Cazombo has become more disconnected. Cazombo ranked 2nd in 1975, 1st in 1976-1990, 3rd in 1991-2000 and 1st in 2001-2014.

Cazombo and Angola do not follow the same trend in the disconnectivity of their aggregate street networks. The SNDi in Cazombo followed a zig-zag trend with an overall increase, while the SNDi of street constructions in Angola peaked in 1991-2000.

To date, Cazombo is the 22nd-most disconnected out of the 51 cities in Angola. Its position in the ranks since 1975 has fallen; relative to other cities in Angola, the street network in Cazombo has become more connected. Cazombo ranked 20th in 1975, 24th in 1976-1990, 34th in 1991-2000 and 22nd in 2001-2014.

As of 2015, Cazombo had a built-up area of 3.03 square kilometers, and a population of 88419 people.

These are some other cities with approximately the same population: