Street-network Sprawl in Amol, Iran

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.

Amol: city in Mazandaran, Iran

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 Amol, Iran on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Amol as of 2014, the overall level of street-network sprawl is 5.25, which is highly disconnected.

Trends in street network construction: The SNDis of street construction for the respective time periods are 5.06, 6.49, 6.28 and 8.39. Disconnectivity in street construction in Amol follows a zig-zag trend. In 1975, street construction was most disconnected, while construction was most connected in 2001-2014.

Quantity of street network construction: The street network in Amol spans a total of 645 kilometers. It is dominated by roads constructed prior to 1975. These roads have an SNDi of 5.06, 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 5.06, 5.24, 5.24 and 5.25. Overall, the SNDi of the aggregate street network has risen: the street network in Amol has become more disconnected. This increase has slowed: between 1975 and 1976-1990, SNDi rose by 0.18 points, but between 1991-2000 and 2001-2014, it rose by just 0.0.

Amol and Mazandaran do not follow the same trend in the disconnectivity of their street network constructions. The SNDi in Amol followed a zig-zag trend with an overall increase, while the SNDi of street constructions in Mazandaran rose steadily.

How do development practices in Amol fare in comparison to others in Mazandaran? Most recently in 2001-2014, street construction in Amol was the 3rd-most disconnected out of the 7 cities in Mazandaran. Its position in the ranks since 1975 has risen; relative to other cities in Mazandaran, street construction in Amol has become more disconnected. Amol ranked 4th in 1975, 3rd in 1976-1990, 5th in 1991-2000 and 3rd in 2001-2014.

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

How do development practices in Amol fare in comparison to others in Iran? Most recently in 2001-2014, street construction in Amol was the 5th-most disconnected out of the 181 cities in Iran. Its position in the ranks since 1975 has risen; relative to other cities in Iran, street construction in Amol has become more disconnected. Amol ranked 15th in 1975, 3rd in 1976-1990, 10th in 1991-2000 and 5th in 2001-2014.

Amol and Mazandaran follow the same trend in the disconnectivity of their aggregate street networks. The SNDi for both of these rose steadily.

To date, Amol is the 3rd-most disconnected out of the 7 cities in Mazandaran. Its position in the ranks since 1975 has risen; relative to other cities in Mazandaran, the street network in Amol has become more disconnected. Amol ranked 4th in 1975, 3rd in 1976-1990, 3rd in 1991-2000 and 3rd in 2001-2014.

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

To date, Amol is the 3rd-most disconnected out of the 181 cities in Iran. Its position in the ranks since 1975 has risen; relative to other cities in Iran, the street network in Amol has become more disconnected. Amol ranked 15th in 1975, 3rd in 1976-1990, 3rd in 1991-2000 and 3rd in 2001-2014.

As of 2015, Amol had a built-up area of 21.0 square kilometers, and a population of 211247 people.

These are some other cities with approximately the same population: