Chengannur 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 Chengannur plotted against Kerala and India. The SNDi of new construction in Chengannur was at its lowest in 1976-1990, compared to Kerala which was at its lowest in 1976-1990 and India which followed a zig-zag trend with an overall increase. Most recently, Chengannur's incremental SNDi rose from 5.0 to 6.72 between 1991-2005 and 2006-2020. In terms of the aggregate network, Chengannur ranked 16th out of 48 cities in Kerala and 1364th out of 1868 in India as of 2020.

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

What about similarly populated cities?

• Talesh, Iran
• WenJiancun, China
• Echizen, Japan
• Karjat, India
• Kankiya, Nigeria
• Maygyr, Uzbekistan

While Talesh and Karjat both built increasingly disconnected streets over time, Chengannur built increasingly connected streets from 1975 through 1976-1990, then shifted to more disconnected patterns in new street additions. Looking at the full network, Talesh and Karjat both became progressively more disconnected, while Chengannur became more connected from 1975 through 1976-1990, then grew more sprawly from 1976-1990 onwards. Notably, Chengannur had a more sprawly network than Karjat in 1975 but the two have since reversed their relative ranking.