Street-network Sprawl in Northern Areas, Pakistan

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.

Northern Areas: region in Pakistan

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 Northern Areas, Pakistan on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Northern Areas as of 2014, the overall level of street-network sprawl is 7.8, which is highly disconnected.

Trends in street network construction: The SNDis of street construction for the respective time periods are 8.61, 5.8, 8.8 and 7.27. Disconnectivity in street construction in Northern Areas 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 Northern Areas spans a total of 2306 kilometers. It is dominated by roads constructed prior to 1975. These roads have an SNDi of 8.61, 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 8.61, 7.8, 7.87 and 7.8. Disconnectivity in Northern Areas's street network follows a zig-zag trend. In 2001-2014, the region was most disconnected; while it was most connected in 1975.

The level of street-network sprawl in new development in Northern Areas followed a zig-zag trend with an overall decrease. To get a sense of how street development has changed in Northern Areas, we can consider two of its most populous cities: Gilgit and Skardu. Out of the two cities, Gilgit does not follow the same trend as the region. The level of street-network sprawl in new development in Gilgit peaked in 1976-1990.

How do development practices in Northern Areas fare in comparison to others in Pakistan? Most recently in 2001-2014, street construction in Northern Areas was the 1st-most disconnected out of the 8 regions in Pakistan. Its position in the ranks since 1975 has not changed. Northern Areas ranked 1st in 1975, 2nd in 1976-1990, 1st in 1991-2000 and 1st in 2001-2014.

As of 2014, the city with the most disconnected street network in Northern Areas is Skardu with an SNDi of 4.49, which is highly disconnected. Conversely, the most connected city is Gilgit with an SNDi of 3.22, which is in the 40th to 60th percentile of disconnectedness. See trends for these cities: Gilgit, Skardu

The level of street-network sprawl in the aggregate network in Northern Areas followed a zig-zag trend with an overall decrease. To get a sense of how the aggregate street network has changed in Northern Areas, we can consider two of its most populous cities: Gilgit and Skardu. None of the most populous cities follow the same trend as the region. The level of street-network sprawl in the aggregate network in Gilgit peaked in 1976-1990. The level of street-network sprawl in the aggregate network in Skardu fell steadily.

To date, Northern Areas is the 1st-most disconnected out of the 8 regions in Pakistan. Its position in the ranks since 1975 has not changed. Northern Areas ranked 1st in 1975, 1st in 1976-1990, 1st in 1991-2000 and 1st in 2001-2014.