Safadasht 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 Safadasht plotted against Alborz and Iran. The SNDi of new construction in Safadasht fell steadily, compared to Alborz which was at its lowest in 1976-1990 and Iran which rose steadily. Most recently, Safadasht's incremental SNDi fell from 3.44 to 3.44 between 1991-2005 and 2006-2020. In terms of the aggregate network, Safadasht ranked 3rd out of 7 cities in Alborz and 127th 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?

• Xinzheng, China
• Siwan, India
• Changxing, China
• Bolingbrook, United States
• Hakodate, Japan
• Mit Habib, Egypt

In new street additions, Safadasht built increasingly connected streets over time, while Xinzheng built increasingly disconnected streets from 1975 through 1976-1990, then improved and Bolingbrook built increasingly disconnected streets from 1975 through 1991-2005, then improved. Looking at the full network, Xinzheng and Bolingbrook both grew more disconnected from 1975 through 1991-2005, then improved, while Safadasht became progressively more connected. Notably, Safadasht had a more sprawly network than Bolingbrook in 1975 but the two have since reversed their relative ranking.