Tongcheng in context: Street-network sprawl trends

Tongcheng in context

1.62.43.24<19751976–19901991–20052006–2020SNDi of street additions
1.62.43.24<19751976–19901991–20052006–2020SNDi of entire street network
TongchengAnhui (Region)China (Country)

The chart above shows SNDi trends for new street additions (left panel) and the entire network (right panel), with Tongcheng plotted against Anhui and China. The SNDi of new construction in Tongcheng peaked in 1991-2005, compared to Anhui which followed a zig-zag trend with an overall increase and China which followed a zig-zag trend with an overall increase. Most recently, Tongcheng's incremental SNDi fell from 3.14 to 2.18 between 1991-2005 and 2006-2020. In terms of the aggregate network, Tongcheng ranked 35th out of 74 cities in Anhui as of 2020.

New Street Additions (2006–2020)

SNDi value
2.18
Rank in Anhui
21st of 74

Entire Network (Aggregate)

SNDi value
2.49
Rank in Anhui
35th of 74

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

What about similarly populated cities?

1.82.73.64.5<19751976–19901991–20052006–2020SNDi of street additions
1.82.73.64.5<19751976–19901991–20052006–2020SNDi of entire street network
TongchengJaspurElgin

In new street additions, Tongcheng built increasingly disconnected streets from 1975 through 1991-2005, then improved, while Jaspur fluctuated in its street-construction patterns and Elgin built increasingly disconnected streets over time. Looking at the full network, Jaspur and Elgin both became progressively more disconnected, while Tongcheng grew more disconnected from 1975 through 1991-2005, then improved. Tongcheng and Elgin have been converging in their street-network character since 1975.