Street-network Sprawl in Girga, Egypt

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.

Girga: city in Suhaj, Egypt

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 Girga, Egypt on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Girga as of 2014, the overall level of street-network sprawl is 4.68, which is highly disconnected.

Trends in street network construction: The SNDis of street construction for the respective time periods are 4.67, 3.54, 9.66 and 7.84. Disconnectivity in street construction in Girga 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 Girga spans a total of 689 kilometers. It is dominated by roads constructed prior to 1975. These roads have an SNDi of 4.67, 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 4.67, 4.62, 4.63 and 4.68. The SNDi of the aggregate street network in fell at first, but Girga has worsened in disconnectivity since 1990.

Girga and Suhaj 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 increase.

How do development practices in Girga fare in comparison to others in Suhaj? Most recently in 2001-2014, street construction in Girga was the 1st-most disconnected out of the 10 cities in Suhaj. Its position in the ranks since 1975 has risen; relative to other cities in Suhaj, street construction in Girga has become more disconnected. Girga ranked 4th in 1975, 3rd in 1976-1990, 1st in 1991-2000 and 1st in 2001-2014.

Girga and Egypt 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 increase.

How do development practices in Girga fare in comparison to others in Egypt? Most recently in 2001-2014, street construction in Girga was the 10th-most disconnected out of the 170 cities in Egypt. Its position in the ranks since 1975 has risen; relative to other cities in Egypt, street construction in Girga has become more disconnected. Girga ranked 46th in 1975, 64th in 1976-1990, 4th in 1991-2000 and 10th in 2001-2014.

Girga and Suhaj follow the same trend in the disconnectivity of their aggregate street networks. The SNDi for both of these was at its lowest in 1976-1990.

To date, Girga is the 4th-most disconnected out of the 10 cities in Suhaj. Its position in the ranks since 1975 has not changed. Girga ranked 4th in 1975, 4th in 1976-1990, 4th in 1991-2000 and 4th in 2001-2014.

Girga and Egypt follow the same trend in the disconnectivity of their aggregate street networks. The SNDi for both of these was at its lowest in 1976-1990.

To date, Girga is the 47th-most disconnected out of the 170 cities in Egypt. Its position in the ranks since 1975 has fallen; relative to other cities in Egypt, the street network in Girga has become more connected. Girga ranked 46th in 1975, 50th in 1976-1990, 47th in 1991-2000 and 47th in 2001-2014.

As of 2015, Girga had a built-up area of 25.89 square kilometers, and a population of 873424 people.

These are some other cities with approximately the same population: