Street-network Sprawl in Kepulauan Riau, 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.

Kepulauan Riau: region in 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 Kepulauan Riau, Indonesia on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Kepulauan Riau as of 2014, the overall level of street-network sprawl is 3.94, which is highly disconnected.

Trends in street network construction: The SNDis of street construction for the respective time periods are 3.95, 8.26, 3.6 and 4.55. Disconnectivity in street construction in Kepulauan Riau follows a zig-zag trend. In 1991-2000, street construction was most disconnected, while construction was most connected in 1976-1990.

Quantity of street network construction: The street network in Kepulauan Riau spans a total of 5129 kilometers. It is dominated by roads constructed prior to 1975. These roads have an SNDi of 3.95, 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 3.95, 4.01, 3.82 and 3.94. Disconnectivity in Kepulauan Riau's street network follows a zig-zag trend. In 1991-2000, the region was most disconnected; while it was most connected in 1976-1990.

The level of street-network sprawl in new development in Kepulauan Riau followed a zig-zag trend with an overall increase. To get a sense of how street development has changed in Kepulauan Riau, we can consider three of its most populous cities: Batam City, Tanjung Balai Karimun and Tanjung Pinang. None of the most populous cities follow the same trend as the region. The level of street-network sprawl in new development in Batam City followed a zig-zag trend with an overall increase. The level of street-network sprawl in new development in Tanjung Balai Karimun followed a zig-zag trend. The level of street-network sprawl in new development in Tanjung Pinang followed a zig-zag trend with an overall increase.

How do development practices in Kepulauan Riau fare in comparison to others in Indonesia? Most recently in 2001-2014, street construction in Kepulauan Riau was the 30th-most disconnected out of the 32 regions in Indonesia. Its position in the ranks since 1975 has fallen; relative to other regions in Indonesia, street construction in Kepulauan Riau has become more connected. Kepulauan Riau ranked 24th in 1975, 1st in 1976-1990, 31st in 1991-2000 and 30th in 2001-2014.

As of 2014, the city with the most disconnected street network in Kepulauan Riau is Tanjung Pinang with an SNDi of 5.51, which is highly disconnected. Conversely, the most connected city is Batam City with an SNDi of 2.86, which is in the 40th to 60th percentile of disconnectedness. See trends for these cities: Batam City, Tanjung Pinang

The level of street-network sprawl in the aggregate network in Kepulauan Riau followed a zig-zag trend with an overall decrease. To get a sense of how the aggregate street network has changed in Kepulauan Riau, we can consider three of its most populous cities: Batam City, Tanjung Balai Karimun and Tanjung Pinang. None of the most populous cities follow the same trend as the region. The level of street-network sprawl in the aggregate network in Batam City followed a zig-zag trend with an overall decrease. The level of street-network sprawl in the aggregate network in Tanjung Balai Karimun followed a zig-zag trend with an overall increase. The level of street-network sprawl in the aggregate network in Tanjung Pinang rose steadily.

To date, Kepulauan Riau is the 29th-most disconnected out of the 32 regions in Indonesia. Its position in the ranks since 1975 has fallen; relative to other regions in Indonesia, the street network in Kepulauan Riau has become more connected. Kepulauan Riau ranked 24th in 1975, 28th in 1976-1990, 29th in 1991-2000 and 29th in 2001-2014.