Street-network Sprawl in Modena, Italy

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.

Modena: city in Emilia-Romagna, Italy

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 Modena, Italy on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Modena as of 2014, the overall level of street-network sprawl is 1.98, which is relatively well-connected.

Trends in street network construction: The SNDis of street construction for the respective time periods are 1.85, 2.81, 4.34 and 1.99. Street construction in Modena 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 Modena spans a total of 434 kilometers. It is dominated by roads constructed prior to 1975. These roads have an SNDi of 1.85, 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 1.85, 1.95, 1.98 and 1.98. The aggregate street network in Modena increased in disconnectivity initially,but the trend has turned around after 2000.

Modena and Emilia-Romagna follow the same trend in the disconnectivity of their street network constructions. The SNDi for both of these peaked in 1991-2000.

How do development practices in Modena fare in comparison to others in Emilia-Romagna? Most recently in 2001-2014, street construction in Modena was the 7th-most disconnected out of the 9 cities in Emilia-Romagna. Its position in the ranks since 1975 has fallen; relative to other cities in Emilia-Romagna, street construction in Modena has become more connected. Modena ranked 3rd in 1975, 5th in 1976-1990, 2nd in 1991-2000 and 7th in 2001-2014.

Modena and Italy follow the same trend in the disconnectivity of their street network constructions. The SNDi for both of these peaked in 1991-2000.

How do development practices in Modena fare in comparison to others in Italy? Most recently in 2001-2014, street construction in Modena was the 63rd-most disconnected out of the 91 cities in Italy. Its position in the ranks since 1975 has fallen; relative to other cities in Italy, street construction in Modena has become more connected. Modena ranked 37th in 1975, 55th in 1976-1990, 28th in 1991-2000 and 63rd in 2001-2014.

Modena and Emilia-Romagna do not follow the same trend in the disconnectivity of their aggregate street networks. The SNDi in Modena peaked in 1991-2000, while the SNDi of street constructions in Emilia-Romagna rose steadily.

To date, Modena is the 5th-most disconnected out of the 9 cities in Emilia-Romagna. Its position in the ranks since 1975 has fallen; relative to other cities in Emilia-Romagna, the street network in Modena has become more connected. Modena ranked 3rd in 1975, 5th in 1976-1990, 5th in 1991-2000 and 5th in 2001-2014.

Modena and Italy do not follow the same trend in the disconnectivity of their aggregate street networks. The SNDi in Modena peaked in 1991-2000, while the SNDi of street constructions in Italy rose steadily.

To date, Modena is the 45th-most disconnected out of the 91 cities in Italy. Its position in the ranks since 1975 has fallen; relative to other cities in Italy, the street network in Modena has become more connected. Modena ranked 37th in 1975, 45th in 1976-1990, 45th in 1991-2000 and 45th in 2001-2014.

As of 2015, Modena had a built-up area of 20.79 square kilometers, and a population of 142870 people.

These are some other cities with approximately the same population: