Luanchuan in context: Street-network sprawl trends

The chart above shows SNDi trends for new street additions (left panel) and the entire network (right panel), with Luanchuan plotted against Henan and China. The SNDi of new construction in Luanchuan was at its lowest in 1976-1990, compared to Henan which peaked in 1976-1990 and China which followed a zig-zag trend with an overall increase. Most recently, Luanchuan's incremental SNDi rose from 1.05 to 1.71 between 1991-2005 and 2006-2020. In terms of the aggregate network, Luanchuan ranked 4th out of 129 cities in Henan and 26th out of 1843 in China as of 2020.

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

What about similarly populated cities?

• Meftah, Algeria
• Ali Sabieh, Djibouti
• Otaru, Japan
• Suraimanpur, India
• Taikang, China
• Pingluo, China

In new street additions, Luanchuan built increasingly connected streets from 1975 through 1976-1990, then shifted to more disconnected patterns, while Meftah built increasingly disconnected streets over time and Suraimanpur built increasingly connected streets from 1975 through 1991-2005, then shifted to more disconnected patterns. For the full network, Luanchuan and Suraimanpur both became more connected from 1975 through 1991-2005, then grew more sprawly from 1991-2005 onwards, while Meftah became progressively more disconnected. Luanchuan and Meftah have been growing further apart in their street-network character since 1975.