Street-network Sprawl in Kétao, Togo

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.

Kétao: city in Kara, Togo

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 Kétao, Togo on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Kétao as of 2014, the overall level of street-network sprawl is -0.28, which is very well-connected.

Trends in street network construction: The SNDis of street construction for the respective time periods are -0.94, -0.49, 0.41 and 0.64. In each period, new street development in Kétao steadily grows more disconnected than in the last. This increase has slowed: between 1975 and 1976-1990, SNDi rose by 0.45 points, but between 1991-2000 and 2001-2014, it rose by just 0.23.

Quantity of street network construction: The street network in Kétao spans a total of 30 kilometers. It is dominated by roads constructed in 1976-1990. These roads have an SNDi of -0.49, 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 -0.94, -0.69, -0.57 and -0.28. Overall, the SNDi of the aggregate street network has risen: the street network in Kétao has become more disconnected.

Kétao and Kara follow the same trend in the disconnectivity of their street network constructions. The SNDi for both of these rose steadily.

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

Kétao and Togo follow the same trend in the disconnectivity of their street network constructions. The SNDi for both of these rose steadily.

How do development practices in Kétao fare in comparison to others in Togo? Most recently in 2001-2014, street construction in Kétao was the 13th-most disconnected out of the 20 cities in Togo. Its position in the ranks since 1975 has fallen; relative to other cities in Togo, street construction in Kétao has become more connected. Kétao ranked 11th in 1975, 16th in 1976-1990, 15th in 1991-2000 and 13th in 2001-2014.

Kétao and Kara follow the same trend in the disconnectivity of their aggregate street networks. The SNDi for both of these rose steadily.

To date, Kétao is the 4th-most disconnected out of the 4 cities in Kara. Its position in the ranks since 1975 has fallen; relative to other cities in Kara, the street network in Kétao has become more connected. Kétao ranked 2nd in 1975, 4th in 1976-1990, 4th in 1991-2000 and 4th in 2001-2014.

Kétao and Togo follow the same trend in the disconnectivity of their aggregate street networks. The SNDi for both of these rose steadily.

To date, Kétao is the 20th-most disconnected out of the 20 cities in Togo. Its position in the ranks since 1975 has fallen; relative to other cities in Togo, the street network in Kétao has become more connected. Kétao ranked 11th in 1975, 18th in 1976-1990, 19th in 1991-2000 and 20th in 2001-2014.

As of 2015, Kétao had a built-up area of 0.16 square kilometers, and a population of 52102 people.

These are some other cities with approximately the same population: