Street-network Sprawl in Tarakan, Indonesia

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.

Tarakan: city in Kalimantan Timur, Indonesia

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 Tarakan, Indonesia on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Tarakan as of 2014, the overall level of street-network sprawl is 7.04, which is highly disconnected.

Trends in street network construction: The SNDis of street construction for the respective time periods are 7.11, 6.89, nan and 9.49. Data was not available in 1991-2000.

Quantity of street network construction: The street network in Tarakan spans a total of 182 kilometers. It is dominated by roads constructed in 1976-1990. These roads have an SNDi of 6.89, which is highly disconnected.

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 7.11, 6.96, 6.96 and 7.04. The SNDi of the aggregate street network in fell at first, but Tarakan has worsened in disconnectivity since 1990.

Tarakan and Kalimantan Timur do not follow the same trend in the disconnectivity of their street network constructions. There was not enough data from the city, while the SNDi of street constructions in Kalimantan Timur peaked in 1991-2000.

How do development practices in Tarakan fare in comparison to others in Kalimantan Timur? Most recently in 2001-2014, street construction in Tarakan was the 1st-most disconnected out of the 11 cities in Kalimantan Timur. Its position in the ranks since 1975 has not changed. Tarakan ranked 1st in 1975, 1st in 1976-1990 and 1st in 2001-2014. There was no ranking in 1991-2000 due to unavailable data.

Tarakan and Indonesia do not follow the same trend in the disconnectivity of their street network constructions. There was not enough data from the city, while the SNDi of street constructions in Indonesia followed a zig-zag trend with an overall increase.

How do development practices in Tarakan fare in comparison to others in Indonesia? Most recently in 2001-2014, street construction in Tarakan was the 8th-most disconnected out of the 363 cities in Indonesia. Its position in the ranks since 1975 has not changed. Tarakan ranked 6th in 1975, 6th in 1976-1990 and 8th in 2001-2014. There was no ranking in 1991-2000 due to unavailable data.

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

To date, Tarakan is the 1st-most disconnected out of the 11 cities in Kalimantan Timur. Its position in the ranks since 1975 has not changed. Tarakan ranked 1st in 1975, 1st in 1976-1990, 1st in 1991-2000 and 1st in 2001-2014.

Tarakan and Indonesia 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, Tarakan is the 7th-most disconnected out of the 363 cities in Indonesia. Its position in the ranks since 1975 has fallen; relative to other cities in Indonesia, the street network in Tarakan has become more connected. Tarakan ranked 6th in 1975, 5th in 1976-1990, 4th in 1991-2000 and 7th in 2001-2014.

As of 2015, Tarakan had a built-up area of 9.31 square kilometers, and a population of 213688 people.

These are some other cities with approximately the same population: