Street-network Sprawl in Farah, Afghanistan

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.

Farah: city in Afghanistan

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 Farah, Afghanistan on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Farah as of 2014, the overall level of street-network sprawl is 2.21, which is relatively well-connected.

Trends in street network construction: The SNDis of street construction for the respective time periods are 2.38, 1.85, 3.66 and 1.3. Disconnectivity in street construction in Farah follows a zig-zag trend. In 2001-2014, street construction was most disconnected, while construction was most connected in 1991-2000.

Quantity of street network construction: The street network in Farah spans a total of 86 kilometers. It is dominated by roads constructed prior to 1975. These roads have an SNDi of 2.38, which is in the 40th to 60th percentile of disconnectedness.

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 2.38, 2.19, 2.27 and 2.21. Disconnectivity in Farah's street network follows a zig-zag trend. In 1976-1990, the city was most disconnected; while it was most connected in 1975.

Farah and Farah follow the same trend in the disconnectivity of their street network constructions. The SNDi for both of these followed a zig-zag trend with an overall decrease.

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

Farah and Afghanistan follow the same trend in the disconnectivity of their street network constructions. The SNDi for both of these followed a zig-zag trend with an overall decrease.

How do development practices in Farah fare in comparison to others in Afghanistan? Most recently in 2001-2014, street construction in Farah was the 18th-most disconnected out of the 40 cities in Afghanistan. Its position in the ranks since 1975 has fallen; relative to other cities in Afghanistan, street construction in Farah has become more connected. Farah ranked 14th in 1975, 13th in 1976-1990, 11th in 1991-2000 and 18th in 2001-2014.

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

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

Farah and Afghanistan follow the same trend in the disconnectivity of their aggregate street networks. The SNDi for both of these followed a zig-zag trend with an overall decrease.

To date, Farah is the 23rd-most disconnected out of the 40 cities in Afghanistan. Its position in the ranks since 1975 has fallen; relative to other cities in Afghanistan, the street network in Farah has become more connected. Farah ranked 14th in 1975, 19th in 1976-1990, 22nd in 1991-2000 and 23rd in 2001-2014.

As of 2015, Farah had a built-up area of 3.89 square kilometers, and a population of 122843 people.

These are some other cities with approximately the same population: