Street-network Sprawl in 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.

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 Indonesia on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Indonesia as of 2014, the overall level of street-network sprawl is 5.6, which is highly disconnected.

Trends in street network construction: The SNDis of street construction for the respective time periods are 5.71, 4.78, 6.43 and 6.34. Disconnectivity in street construction in Indonesia 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 Indonesia spans a total of 754804 kilometers. The period with the greatest volume of street construction was 1975. These roads have an SNDi of 5.71, 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 5.71, 5.33, 5.49 and 5.6. The SNDi of the aggregate street network in fell at first, but Indonesia has worsened in disconnectivity since 1990.

The level of street-network sprawl in new development in Indonesia followed a zig-zag trend with an overall increase. To get a sense of how street development has changed in Indonesia, we can consider three of its most populous regions: Jawa Barat, Jawa Timur and Jawa Tengah. None of the most populous cities follow the same trend as the region. The level of street-network sprawl in new development in Jawa Barat peaked in 1991-2000. The level of street-network sprawl in new development in Jawa Timur rose steadily. The level of street-network sprawl in new development in Jawa Tengah was at its lowest in 1976-1990.

How do development practices in Indonesia fare in comparison to others in the world? Most recently in 2001-2014, street construction in Indonesia was the 21st-most disconnected out of the 155 countries in the world. Its position in the ranks since 1975 has fallen; relative to other countries in the world, street construction in Indonesia has become more connected. Indonesia ranked 7th in 1975, 30th in 1976-1990, 16th in 1991-2000 and 21st in 2001-2014.

The largest city in Indonesia is Jakarta, with a population of 36312500 people. Taking into account the entire (i.e. aggregate) street network in Jakarta as of 2014, the overall level of street-network sprawl is 4.53, which is highly disconnected. The level of street-network sprawl in new development in Jakarta rose steadily.

As of 2014, the city with the most disconnected street network in Indonesia is Mentengsari with an SNDi of 8.73, which is highly disconnected. Conversely, the most connected city is Panjunan with an SNDi of -1.56, which is very well-connected. See trends for these cities: Panjunan, Mentengsari

The level of street-network sprawl in the aggregate network in Indonesia was at its lowest in 1976-1990. To get a sense of how the aggregate street network has changed in Indonesia, we can consider three of its most populous regions: Jawa Barat, Jawa Timur and Jawa Tengah. Out of the three regions, Jawa Barat and Jawa Timur do not follow the same trend as the country. The level of street-network sprawl in the aggregate network in Jawa Barat rose steadily. The level of street-network sprawl in the aggregate network in Jawa Timur rose steadily.

To date, Indonesia is the 11th-most disconnected out of the 155 countries in the world. Its position in the ranks since 1975 has fallen; relative to other countries in the world, the street network in Indonesia has become more connected. Indonesia ranked 7th in 1975, 11th in 1976-1990, 11th in 1991-2000 and 11th in 2001-2014.

The largest city in Indonesia is Jakarta, with a population of 36312500 people. Taking into account the entire (i.e. aggregate) street network in Jakarta as of 2014, the overall level of street-network sprawl is 4.53, which is highly disconnected. The level of street-network sprawl in the aggregate network in Jakarta rose steadily.