Street-network Sprawl in Khartoum, Sudan


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 10262 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.

Khartoum: city in Sudan

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 Khartoum, Sudan on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Khartoum as of 2014, the overall level of street-network sprawl is 0.43, which is very well-connected.

Trends in street network construction: The SNDis of street construction for the respective time periods are 0.32, 0.23, 0.57 and 0.68. The disconnectivity of new streets constructed in Khartoum fell, then rose. In 1976-1990, new street layouts were the most connected.

Quantity of street network construction: The street network in Khartoum spans a total of 12281 kilometers. It is dominated by roads constructed prior to 1975. These roads have an SNDi of 0.32, 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 0.32, 0.29, 0.3 and 0.43. The SNDi of the aggregate street network in fell at first, but Khartoum has worsened in disconnectivity since 1990.

Khartoum and Khartoum follow the same trend in the disconnectivity of their street network constructions. The SNDi for both of these was at its lowest in 1976-1990.

How do development practices in Khartoum fare in comparison to others in Khartoum? Most recently in 2001-2014, street construction in Khartoum was the 1st-most disconnected out of the 4 cities in Khartoum. Its position in the ranks since 1975 has risen; relative to other cities in Khartoum, street construction in Khartoum has become more disconnected. Khartoum ranked 3rd in 1975, 2nd in 1976-1990, 1st in 1991-2000 and 1st in 2001-2014.

Khartoum and Sudan do not follow the same trend in the disconnectivity of their street network constructions. The SNDi in Khartoum was at its lowest in 1976-1990, while the SNDi of street constructions in Sudan peaked in 1991-2000.

How do development practices in Khartoum fare in comparison to others in Sudan? Most recently in 2001-2014, street construction in Khartoum was the 26th-most disconnected out of the 63 cities in Sudan. Its position in the ranks since 1975 has fallen; relative to other cities in Sudan, street construction in Khartoum has become more connected. Khartoum ranked 18th in 1975, 26th in 1976-1990, 23rd in 1991-2000 and 26th in 2001-2014.

Khartoum and Khartoum follow the same trend in the disconnectivity of their aggregate street networks. The SNDi for both of these was at its lowest in 1976-1990.

To date, Khartoum is the 3rd-most disconnected out of the 4 cities in Khartoum. Its position in the ranks since 1975 has not changed. Khartoum ranked 3rd in 1975, 3rd in 1976-1990, 3rd in 1991-2000 and 3rd in 2001-2014.

Khartoum and Sudan do not follow the same trend in the disconnectivity of their aggregate street networks. The SNDi in Khartoum was at its lowest in 1976-1990, while the SNDi of street constructions in Sudan rose steadily.

To date, Khartoum is the 37th-most disconnected out of the 63 cities in Sudan. Its position in the ranks since 1975 has fallen; relative to other cities in Sudan, the street network in Khartoum has become more connected. Khartoum ranked 18th in 1975, 25th in 1976-1990, 31st in 1991-2000 and 37th in 2001-2014.

As of 2015, Khartoum had a built-up area of 264.52 square kilometers, and a population of 5824720 people.

These are some other cities with approximately the same population:

For some related information about population, urban extent and density, and roads, visit the Atlas of Urban Expansion.