Illela in context: Street-network sprawl trends

Illela in context

1.82.12.42.7<19751976–19901991–20052006–2020SNDi of street additions
1.82.12.42.7<19751976–19901991–20052006–2020SNDi of entire street network
IllelaTahoua (Region)Niger (Country)

The chart above shows SNDi trends for new street additions (left panel) and the entire network (right panel), with Illela plotted against Tahoua and Niger. The SNDi of new construction in Illela was at its lowest in 1991-2005, compared to Tahoua which rose steadily and Niger which rose steadily. Most recently, Illela's incremental SNDi rose from 2.01 to 2.02 between 1991-2005 and 2006-2020. In terms of the aggregate network, Illela ranked 5th out of 8 cities in Tahoua and 24th out of 33 in Niger as of 2020.

New Street Additions (2006–2020)

SNDi value
2.02
Rank in Niger
14th of 33
Rank in Tahoua
3rd of 8

Entire Network (Aggregate)

SNDi value
2.08
Rank in Niger
24th of 33
Rank in Tahoua
5th of 8

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

What about similarly populated cities?

123456<19751976–19901991–20052006–2020SNDi of street additions
123456<19751976–19901991–20052006–2020SNDi of entire street network
IllelaQarabagOkopedi

In new street additions, Illela built increasingly connected streets from 1975 through 1991-2005, then shifted to more disconnected patterns, while Qarabāg fluctuated in its street-construction patterns and Okopedi fluctuated in its street-construction patterns. For the full network, Illela became progressively more connected, while Qarabāg became progressively more connected and Okopedi fluctuated in connectivity. Notably, Illela had a more sprawly network than Okopedi in 1975 but the two have since reversed their relative ranking.