Heyang in context: Street-network sprawl trends

Heyang in context

2345<19751976–19901991–20052006–2020SNDi of street additions
2345<19751976–19901991–20052006–2020SNDi of entire street network
HeyangShaanxi (Region)China (Country)

The chart above shows SNDi trends for new street additions (left panel) and the entire network (right panel), with Heyang plotted against Shaanxi and China. The SNDi of new construction in Heyang peaked in 1991-2005, compared to Shaanxi which peaked in 1976-1990 and China which followed a zig-zag trend with an overall increase. Most recently, Heyang's incremental SNDi fell from 2.8 to 2.57 between 1991-2005 and 2006-2020. In terms of the aggregate network, Heyang ranked 10th out of 62 cities in Shaanxi and 387th out of 1843 in China as of 2020.

New Street Additions (2006–2020)

SNDi value
2.57
Rank in China
562nd of 1843
Rank in Shaanxi
19th of 62

Entire Network (Aggregate)

SNDi value
2.24
Rank in China
387th of 1843
Rank in Shaanxi
10th of 62

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

What about similarly populated cities?

2468<19751976–19901991–20052006–2020SNDi of street additions
2468<19751976–19901991–20052006–2020SNDi of entire street network
HeyangMadabaAlessandria

In new street additions, Heyang and Alessandria both built increasingly disconnected streets from 1975 through 1991-2005, then improved, while Madaba built increasingly connected streets from 1975 through 1991-2005, then shifted to more disconnected patterns. For the full network, Heyang and Alessandria both became progressively more disconnected, while Madaba became more connected from 1975 through 1991-2005, then grew more sprawly from 1991-2005 onwards. Notably, Heyang had a more connected network than Alessandria in 1975 but the two have since reversed their relative ranking.