Street-network Sprawl in Omoko, 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.

Omoko: city in Rivers, 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 Omoko, Nigeria on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Omoko as of 2014, the overall level of street-network sprawl is 1.36, which is relatively well-connected.

Trends in street network construction: The SNDis of street construction for the respective time periods are 1.89, 0.51, 4.04 and 2.32. Disconnectivity in street construction in Omoko follows a zig-zag trend. In 1976-1990, street construction was most disconnected, while construction was most connected in 1991-2000.

Quantity of street network construction: The street network in Omoko spans a total of 154 kilometers. It is dominated by roads constructed in 2001-2014. These roads have an SNDi of 2.32, 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 1.89, 0.58, 0.72 and 1.36. The SNDi of the aggregate street network in fell at first, but Omoko has worsened in disconnectivity since 1990.

Omoko and Rivers do not follow the same trend in the disconnectivity of their street network constructions. The SNDi in Omoko followed a zig-zag trend with an overall increase, while the SNDi of street constructions in Rivers rose steadily.

How do development practices in Omoko fare in comparison to others in Rivers? Most recently in 2001-2014, street construction in Omoko was the 13th-most disconnected out of the 15 cities in Rivers. Its position in the ranks since 1975 has fallen; relative to other cities in Rivers, street construction in Omoko has become more connected. Omoko ranked 9th in 1975, 15th in 1976-1990, 9th in 1991-2000 and 13th in 2001-2014.

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

How do development practices in Omoko fare in comparison to others in Nigeria? Most recently in 2001-2014, street construction in Omoko was the 214th-most disconnected 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 Omoko has become more connected. Omoko ranked 97th in 1975, 256th in 1976-1990, 85th in 1991-2000 and 214th in 2001-2014.

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

To date, Omoko is the 14th-most disconnected out of the 15 cities in Rivers. Its position in the ranks since 1975 has fallen; relative to other cities in Rivers, the street network in Omoko has become more connected. Omoko ranked 9th in 1975, 15th in 1976-1990, 15th in 1991-2000 and 14th in 2001-2014.

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

To date, Omoko is the 246th-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 Omoko has become more connected. Omoko ranked 97th in 1975, 250th in 1976-1990, 260th in 1991-2000 and 246th in 2001-2014.

As of 2015, Omoko had a built-up area of 7.12 square kilometers, and a population of 122864 people.

These are some other cities with approximately the same population: