Sanandaj 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 Sanandaj plotted against Kordestan and Iran. All three follow the same trend in new construction, suggesting a shared regional pattern of development. Most recently, Sanandaj's incremental SNDi rose from 3.73 to 4.75 between 1991-2005 and 2006-2020. In terms of the aggregate network, Sanandaj ranked 4th out of 4 cities in Kordestan and 91st out of 169 in Iran as of 2020.

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

What about similarly populated cities?

• Aizawl, India
• Qidong, China
• Novokuznetsk, Russia
• Yibin, China
• Yuanlin City, Taiwan
• Bo, Sierra Leone

In new street additions, Sanandaj built increasingly disconnected streets over time, while Aizawl built increasingly disconnected streets from 1975 through 1991-2005, then improved and Yibin built increasingly connected streets from 1975 through 1976-1990, then shifted to more disconnected patterns. For the full network, Sanandaj and Aizawl both became progressively more disconnected, while Yibin became more connected from 1975 through 1991-2005, then grew more sprawly from 1991-2005 onwards. Notably, Sanandaj had a more connected network than Yibin in 1975 but the two have since reversed their relative ranking.