Lanzhou in context: Street-network sprawl trends

Lanzhou in context

3.54.24.95.6<19751976–19901991–20052006–2020SNDi of street additions
3.54.24.95.6<19751976–19901991–20052006–2020SNDi of entire street network
LanzhouGansu (Region)China (Country)

The chart above shows SNDi trends for new street additions (left panel) and the entire network (right panel), with Lanzhou plotted against Gansu and China. While Gansu and China both followed a zig-zag trend with an overall increase, Lanzhou's new street additions followed a zig-zag trend with an overall increase. Most recently, Lanzhou's incremental SNDi rose from 5.22 to 5.45 between 1991-2005 and 2006-2020. In terms of the aggregate network, Lanzhou ranked 20th out of 29 cities in Gansu and 1731st out of 1843 in China as of 2020.

New Street Additions (2006–2020)

SNDi value
5.45
Rank in China
1699th of 1843
Rank in Gansu
23rd of 29

Entire Network (Aggregate)

SNDi value
5.09
Rank in China
1731st of 1843
Rank in Gansu
20th of 29

Rankings go from most connected to most disconnected — rank 1 is the most connected.

What about similarly populated cities?

2345<19751976–19901991–20052006–2020SNDi of street additions
2345<19751976–19901991–20052006–2020SNDi of entire street network
LanzhouDaeguManchester

In new street additions, Lanzhou and Daegu both fluctuated in its street-construction patterns, while Manchester built increasingly disconnected streets from 1975 through 1991-2005, then improved. For the full street network, though, all three cities follow the same trend.