Street-network Sprawl in Roudan, 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.

Roudan: city in Hormozgan, 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 Roudan, Iran on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Roudan as of 2014, the overall level of street-network sprawl is 2.61, which is in the 40th to 60th percentile of disconnectedness.

Trends in street network construction: The SNDis of street construction for the respective time periods are 3.17, 0.62, 2.55 and 1.54. Disconnectivity in street construction in Roudan follows a zig-zag trend. In 1976-1990, street construction was most disconnected, while construction was most connected in 1975.

Quantity of street network construction: The street network in Roudan spans a total of 41 kilometers. It is dominated by roads constructed prior to 1975. These roads have an SNDi of 3.17, 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 3.17, 2.62, 2.98 and 2.61. Disconnectivity in Roudan's street network follows a zig-zag trend. In 2001-2014, the city was most disconnected; while it was most connected in 1975.

Roudan and Hormozgan 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 Roudan fare in comparison to others in Hormozgan? Most recently in 2001-2014, street construction in Roudan was the 3rd-most disconnected out of the 3 cities in Hormozgan. Its position in the ranks since 1975 has fallen; relative to other cities in Hormozgan, street construction in Roudan has become more connected. Roudan ranked 2nd in 1975, 3rd in 1976-1990, 1st in 1991-2000 and 3rd in 2001-2014.

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

How do development practices in Roudan fare in comparison to others in Iran? Most recently in 2001-2014, street construction in Roudan was the 144th-most disconnected out of the 181 cities in Iran. Its position in the ranks since 1975 has fallen; relative to other cities in Iran, street construction in Roudan has become more connected. Roudan ranked 43rd in 1975, 152nd in 1976-1990, 74th in 1991-2000 and 144th in 2001-2014.

Roudan and Hormozgan 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, Roudan is the 2nd-most disconnected out of the 3 cities in Hormozgan. Its position in the ranks since 1975 has not changed. Roudan ranked 2nd in 1975, 1st in 1976-1990, 1st in 1991-2000 and 2nd in 2001-2014.

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

To date, Roudan is the 62nd-most disconnected out of the 181 cities in Iran. Its position in the ranks since 1975 has fallen; relative to other cities in Iran, the street network in Roudan has become more connected. Roudan ranked 43rd in 1975, 47th in 1976-1990, 39th in 1991-2000 and 62nd in 2001-2014.

As of 2015, Roudan had a built-up area of 2.22 square kilometers, and a population of 66499 people.

These are some other cities with approximately the same population: