Street-network Sprawl in Mehrestan, 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.

Mehrestan: city in Sistan and Baluchestan, 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 Mehrestan, Iran on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Mehrestan as of 2014, the overall level of street-network sprawl is 0.13, which is very well-connected.

Trends in street network construction: The SNDis of street construction for the respective time periods are 1.12, -1.24, nan and -0.44. Data was not available in 1991-2000.

Quantity of street network construction: The street network in Mehrestan spans a total of 27 kilometers. It is dominated by roads constructed prior to 1975. These roads have an SNDi of 1.12, which is relatively well-connected.

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 1.12, 0.3, 0.3 and 0.13. Overall, the SNDi of the aggregate street network has fallen: the street network in Mehrestan has become more connected.

Mehrestan and Sistan and Baluchestan do not follow the same trend in the disconnectivity of their street network constructions. There was not enough data from the city, while the SNDi of street constructions in Sistan and Baluchestan followed a zig-zag trend with an overall decrease.

How do development practices in Mehrestan fare in comparison to others in Sistan and Baluchestan? Most recently in 2001-2014, street construction in Mehrestan was the 9th-most disconnected out of the 9 cities in Sistan and Baluchestan. Its position in the ranks since 1975 has fallen; relative to other cities in Sistan and Baluchestan, street construction in Mehrestan has become more connected. Mehrestan ranked 6th in 1975, 8th in 1976-1990 and 9th in 2001-2014. There was no ranking in 1991-2000 due to unavailable data.

Mehrestan and Iran do not follow the same trend in the disconnectivity of their street network constructions. There was not enough data from the city, while the SNDi of street constructions in Iran was at its lowest in 1976-1990.

How do development practices in Mehrestan fare in comparison to others in Iran? Most recently in 2001-2014, street construction in Mehrestan was the 175th-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 Mehrestan has become more connected. Mehrestan ranked 106th in 1975, 173rd in 1976-1990 and 175th in 2001-2014. There was no ranking in 1991-2000 due to unavailable data.

Mehrestan and Sistan and Baluchestan do not follow the same trend in the disconnectivity of their aggregate street networks. The SNDi in Mehrestan fell steadily, while the SNDi of street constructions in Sistan and Baluchestan fell steadily.

To date, Mehrestan is the 9th-most disconnected out of the 9 cities in Sistan and Baluchestan. Its position in the ranks since 1975 has fallen; relative to other cities in Sistan and Baluchestan, the street network in Mehrestan has become more connected. Mehrestan ranked 6th in 1975, 8th in 1976-1990, 8th in 1991-2000 and 9th in 2001-2014.

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

To date, Mehrestan is the 179th-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 Mehrestan has become more connected. Mehrestan ranked 106th in 1975, 167th in 1976-1990, 173rd in 1991-2000 and 179th in 2001-2014.

As of 2015, Mehrestan had a built-up area of 0.16 square kilometers, and a population of 50127 people.

These are some other cities with approximately the same population: