Colmar 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 Colmar plotted against Grand Est and France. The SNDi of new construction in Colmar followed a zig-zag trend with an overall increase, compared to Grand Est which rose steadily and France which peaked in 1991-2005. Most recently, Colmar's incremental SNDi rose from 2.59 to 6.08 between 1991-2005 and 2006-2020. In terms of the aggregate network, Colmar ranked 1st out of 7 cities in Grand Est and 4th out of 73 in France as of 2020.

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

What about similarly populated cities?

• Weiqiao, China
• Nidadavolu, India
• Maïné-Soroa, Niger
• Kachhwa, India
• Nattalin, Myanmar
• Kluwut, Indonesia

In new street additions, Colmar fluctuated in its street-construction patterns, while Weiqiao built increasingly connected streets from 1975 through 1991-2005, then shifted to more disconnected patterns and Kachhwa built increasingly disconnected streets over time. For the full network, Colmar and Kachhwa both became progressively more disconnected, while Weiqiao became progressively more connected. Notably, Colmar had a more connected network than Weiqiao in 1975 but the two have since reversed their relative ranking.