Street-network Sprawl in Bayreuth, Germany

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.

Bayreuth: city in Bayern, Germany

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 Bayreuth, Germany on the sprawlmap

Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Bayreuth as of 2014, the overall level of street-network sprawl is 0.69, which is relatively well-connected.

Trends in street network construction: The SNDis of street construction for the respective time periods are 0.47, 1.72, 2.17 and 0.93. Street construction in Bayreuth 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 Bayreuth spans a total of 225 kilometers. It is dominated by roads constructed prior to 1975. These roads have an SNDi of 0.47, 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 0.47, 0.67, 0.69 and 0.69. The aggregate street network in Bayreuth increased in disconnectivity initially,but the trend has turned around after 2000.

Bayreuth and Bayern 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 Bayreuth fare in comparison to others in Bayern? Most recently in 2001-2014, street construction in Bayreuth was the 9th-most disconnected out of the 13 cities in Bayern. Its position in the ranks since 1975 has risen; relative to other cities in Bayern, street construction in Bayreuth has become more disconnected. Bayreuth ranked 12th in 1975, 8th in 1976-1990, 6th in 1991-2000 and 9th in 2001-2014.

Bayreuth and Germany 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 Bayreuth fare in comparison to others in Germany? Most recently in 2001-2014, street construction in Bayreuth was the 76th-most disconnected out of the 87 cities in Germany. Its position in the ranks since 1975 has risen; relative to other cities in Germany, street construction in Bayreuth has become more disconnected. Bayreuth ranked 83rd in 1975, 59th in 1976-1990, 42nd in 1991-2000 and 76th in 2001-2014.

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

To date, Bayreuth is the 12th-most disconnected out of the 13 cities in Bayern. Its position in the ranks since 1975 has not changed. Bayreuth ranked 12th in 1975, 12th in 1976-1990, 12th in 1991-2000 and 12th in 2001-2014.

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

To date, Bayreuth is the 80th-most disconnected out of the 87 cities in Germany. Its position in the ranks since 1975 has risen; relative to other cities in Germany, the street network in Bayreuth has become more disconnected. Bayreuth ranked 83rd in 1975, 80th in 1976-1990, 80th in 1991-2000 and 80th in 2001-2014.

As of 2015, Bayreuth had a built-up area of 11.59 square kilometers, and a population of 56230 people.

These are some other cities with approximately the same population: