Street-network Sprawl in Ceyhan, Turkey

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.

Ceyhan: city in Adana, Turkey

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 Ceyhan, Turkey on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Ceyhan as of 2014, the overall level of street-network sprawl is 0.63, which is relatively well-connected.

Trends in street network construction: The SNDis of street construction for the respective time periods are 0.45, 0.36, 2.4 and 1.27. Disconnectivity in street construction in Ceyhan 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 Ceyhan spans a total of 280 kilometers. It is dominated by roads constructed in 1976-1990. These roads have an SNDi of 0.36, 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 0.45, 0.38, 0.59 and 0.63. The SNDi of the aggregate street network in fell at first, but Ceyhan has worsened in disconnectivity since 1990.

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

How do development practices in Ceyhan fare in comparison to others in Adana? Most recently in 2001-2014, street construction in Ceyhan was the 3rd-most disconnected out of the 6 cities in Adana. Its position in the ranks since 1975 has risen; relative to other cities in Adana, street construction in Ceyhan has become more disconnected. Ceyhan ranked 4th in 1975, 5th in 1976-1990, 1st in 1991-2000 and 3rd in 2001-2014.

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

How do development practices in Ceyhan fare in comparison to others in Turkey? Most recently in 2001-2014, street construction in Ceyhan was the 90th-most disconnected out of the 134 cities in Turkey. Its position in the ranks since 1975 has fallen; relative to other cities in Turkey, street construction in Ceyhan has become more connected. Ceyhan ranked 81st in 1975, 109th in 1976-1990, 35th in 1991-2000 and 90th in 2001-2014.

Ceyhan and Adana 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, Ceyhan is the 5th-most disconnected out of the 6 cities in Adana. Its position in the ranks since 1975 has fallen; relative to other cities in Adana, the street network in Ceyhan has become more connected. Ceyhan ranked 4th in 1975, 6th in 1976-1990, 4th in 1991-2000 and 5th in 2001-2014.

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

To date, Ceyhan is the 98th-most disconnected out of the 134 cities in Turkey. Its position in the ranks since 1975 has fallen; relative to other cities in Turkey, the street network in Ceyhan has become more connected. Ceyhan ranked 81st in 1975, 110th in 1976-1990, 96th in 1991-2000 and 98th in 2001-2014.

As of 2015, Ceyhan had a built-up area of 10.67 square kilometers, and a population of 103840 people.

These are some other cities with approximately the same population: