Street-network Sprawl in Ambo, Ethiopia

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.

Ambo: city in Oromia, Ethiopia

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 Ambo, Ethiopia on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Ambo as of 2014, the overall level of street-network sprawl is 2.5, which is in the 40th to 60th percentile of disconnectedness.

Trends in street network construction: The SNDis of street construction for the respective time periods are 2.79, -0.12, 0.84 and 3.08. The disconnectivity of new streets constructed in Ambo fell, then rose. In 1976-1990, new street layouts were the most connected.

Quantity of street network construction: The street network in Ambo spans a total of 92 kilometers. It is dominated by roads constructed in 2001-2014. These roads have an SNDi of 3.08, 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 2.79, 1.22, 0.99 and 2.5. The SNDi of the aggregate street network in fell at first, but Ambo has worsened in disconnectivity since 2000.

Ambo and Oromia 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 Ambo fare in comparison to others in Oromia? Most recently in 2001-2014, street construction in Ambo was the 16th-most disconnected out of the 106 cities in Oromia. Its position in the ranks since 1975 has fallen; relative to other cities in Oromia, street construction in Ambo has become more connected. Ambo ranked 2nd in 1975, 27th in 1976-1990, 23rd in 1991-2000 and 16th in 2001-2014.

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

How do development practices in Ambo fare in comparison to others in Ethiopia? Most recently in 2001-2014, street construction in Ambo was the 42nd-most disconnected out of the 252 cities in Ethiopia. Its position in the ranks since 1975 has fallen; relative to other cities in Ethiopia, street construction in Ambo has become more connected. Ambo ranked 5th in 1975, 66th in 1976-1990, 63rd in 1991-2000 and 42nd in 2001-2014.

Ambo and Oromia do not follow the same trend in the disconnectivity of their aggregate street networks. The SNDi in Ambo was at its lowest in 1991-2000, while the SNDi of street constructions in Oromia was at its lowest in 1976-1990.

To date, Ambo is the 22nd-most disconnected out of the 106 cities in Oromia. Its position in the ranks since 1975 has fallen; relative to other cities in Oromia, the street network in Ambo has become more connected. Ambo ranked 2nd in 1975, 11th in 1976-1990, 22nd in 1991-2000 and 22nd in 2001-2014.

Ambo and Ethiopia do not follow the same trend in the disconnectivity of their aggregate street networks. The SNDi in Ambo was at its lowest in 1991-2000, while the SNDi of street constructions in Ethiopia followed a zig-zag trend with an overall increase.

To date, Ambo is the 55th-most disconnected out of the 252 cities in Ethiopia. Its position in the ranks since 1975 has fallen; relative to other cities in Ethiopia, the street network in Ambo has become more connected. Ambo ranked 5th in 1975, 31st in 1976-1990, 62nd in 1991-2000 and 55th in 2001-2014.

As of 2015, Ambo had a built-up area of 2.67 square kilometers, and a population of 186744 people.

These are some other cities with approximately the same population: