Salka 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 Salka plotted against Niger and Nigeria. The SNDi of new construction in Salka was at its lowest in 1991-2005, compared to Niger which followed a zig-zag trend with an overall increase and Nigeria which followed a zig-zag trend with an overall increase. Most recently, Salka's incremental SNDi rose from 1.75 to 2.33 between 1991-2005 and 2006-2020. In terms of the aggregate network, Salka ranked 4th out of 13 cities in Niger and 88th out of 422 in Nigeria as of 2020.

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

What about similarly populated cities?

• Ash Shallal, Sudan
• Ash Shuara, Egypt
• Primavera do Leste, Brazil
• Hejie, China
• Akhorwal, Pakistan
• Fuladshahr, Iran

While Ash Shallal and Hejie both fluctuated in its street-construction patterns, Salka built increasingly connected streets from 1975 through 1991-2005, then shifted to more disconnected patterns in new street additions. For the full network, Salka became more connected from 1975 through 1991-2005, then grew more sprawly from 1991-2005 onwards, while Ash Shallal became progressively more disconnected and Hejie fluctuated in connectivity. Salka and Ash Shallal have been converging in their street-network character since 1975.