Street-network Sprawl in Rabat - Salé - Zemmour - Zaer, Morocco

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.

Rabat - Salé - Zemmour - Zaer: region in Morocco

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 Rabat - Salé - Zemmour - Zaer, Morocco on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Rabat - Salé - Zemmour - Zaer as of 2014, the overall level of street-network sprawl is 1.48, which is relatively well-connected.

Trends in street network construction: The SNDis of street construction for the respective time periods are 1.11, 1.63, 1.85 and 1.81. Street construction in Rabat - Salé - Zemmour - Zaer increased in disconnectivity initially but has since improved. The streets constructed in 1991-2000 were the most disconnected.

Quantity of street network construction: The street network in Rabat - Salé - Zemmour - Zaer spans a total of 7132 kilometers. The period with the greatest volume of street construction was 2001-2014. These roads have an SNDi of 1.81, 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 1.11, 1.35, 1.42 and 1.48. Overall, the SNDi of the aggregate street network has risen: the street network in Rabat - Salé - Zemmour - Zaer has become more disconnected. This increase has slowed: between 1975 and 1976-1990, SNDi rose by 0.24 points, but between 1991-2000 and 2001-2014, it rose by just 0.06.

The level of street-network sprawl in new development in Rabat - Salé - Zemmour - Zaer peaked in 1991-2000. To get a sense of how street development has changed in Rabat - Salé - Zemmour - Zaer, we can consider three of its most populous cities: Rabat, Khemisset and Tiflet. Out of the three cities, Rabat and Khemisset do not follow the same trend as the region. The level of street-network sprawl in new development in Rabat rose steadily. The level of street-network sprawl in new development in Khemisset followed a zig-zag trend with an overall increase.

How do development practices in Rabat - Salé - Zemmour - Zaer fare in comparison to others in Morocco? Most recently in 2001-2014, street construction in Rabat - Salé - Zemmour - Zaer was the 9th-most disconnected out of the 14 regions in Morocco. Its position in the ranks since 1975 has risen; relative to other regions in Morocco, street construction in Rabat - Salé - Zemmour - Zaer has become more disconnected. Rabat - Salé - Zemmour - Zaer ranked 11th in 1975, 10th in 1976-1990, 8th in 1991-2000 and 9th in 2001-2014.

As of 2014, the city with the most disconnected street network in Rabat - Salé - Zemmour - Zaer is Rabat with an SNDi of 1.31, which is relatively well-connected. Conversely, the most connected city is Ain El Aouda with an SNDi of 0.53, which is relatively well-connected. See trends for these cities: Ain El Aouda, Rabat

The level of street-network sprawl in the aggregate network in Rabat - Salé - Zemmour - Zaer rose steadily. To get a sense of how the aggregate street network has changed in Rabat - Salé - Zemmour - Zaer, we can consider three of its most populous cities: Rabat, Khemisset and Tiflet. Out of the three cities, Khemisset and Tiflet do not follow the same trend as the region. The level of street-network sprawl in the aggregate network in Khemisset was at its lowest in 1976-1990. The level of street-network sprawl in the aggregate network in Tiflet peaked in 1976-1990.

To date, Rabat - Salé - Zemmour - Zaer is the 11th-most disconnected out of the 14 regions in Morocco. Its position in the ranks since 1975 has not changed. Rabat - Salé - Zemmour - Zaer ranked 11th in 1975, 11th in 1976-1990, 11th in 1991-2000 and 11th in 2001-2014.