Mile 91 in context: Street-network sprawl trends

Mile 91 in context

23456<19751976–19901991–20052006–2020SNDi of street additions
23456<19751976–19901991–20052006–2020SNDi of entire street network
Mile 91Northern (Region)Sierra Leone (Country)

The chart above shows SNDi trends for new street additions (left panel) and the entire network (right panel), with Mile 91 plotted against Northern and Sierra Leone. All three follow the same trend in new construction, suggesting a shared regional pattern of development. Most recently, Mile 91's incremental SNDi rose from 3.81 to 4.76 between 1991-2005 and 2006-2020. In terms of the aggregate network, Mile 91 ranked 2nd out of 7 cities in Northern and 2nd out of 12 in Sierra Leone as of 2020.

New Street Additions (2006–2020)

SNDi value
4.76
Rank in Sierra Leone
3rd of 12
Rank in Northern
2nd of 7

Entire Network (Aggregate)

SNDi value
3.13
Rank in Sierra Leone
2nd of 12
Rank in Northern
2nd of 7

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

What about similarly populated cities?

12345<19751976–19901991–20052006–2020SNDi of street additions
12345<19751976–19901991–20052006–2020SNDi of entire street network
Mile 91AltamuraChicago Heights

While Altamura and Chicago Heights both built increasingly disconnected streets from 1975 through 1991-2005, then improved, Mile 91 built increasingly disconnected streets over time in new street additions. For the full street network, though, all three cities follow the same trend. Notably, Mile 91 had a more connected network than Chicago Heights in 1975 but the two have since reversed their relative ranking.