Erode 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 Erode plotted against Tamil Nadu and India. The SNDi of new construction in Erode rose steadily, compared to Tamil Nadu which rose steadily and India which followed a zig-zag trend with an overall increase. Most recently, Erode's incremental SNDi rose from 4.07 to 5.22 between 1991-2005 and 2006-2020. In terms of the aggregate network, Erode ranked 61st out of 121 cities in Tamil Nadu and 954th 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?

• Darbhanga, India
• Ulsan, South Korea
• Bayamón [San Juan], Puerto Rico
• Herat, Afghanistan
• San Miguel de Tucumán, Argentina
• Voronezh, Russia

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