Port Harcourt in context: Street-network sprawl trends

Port Harcourt in context

3.244.85.6<19751976–19901991–20052006–2020SNDi of street additions
3.244.85.6<19751976–19901991–20052006–2020SNDi of entire street network
Port HarcourtRivers (Region)Nigeria (Country)

The chart above shows SNDi trends for new street additions (left panel) and the entire network (right panel), with Port Harcourt plotted against Rivers and Nigeria. While Rivers and Nigeria both followed a zig-zag trend with an overall increase, Port Harcourt's new street additions followed a zig-zag trend with an overall increase. Most recently, Port Harcourt's incremental SNDi rose from 5.53 to 5.77 between 1991-2005 and 2006-2020. In terms of the aggregate network, Port Harcourt ranked 19th out of 28 cities in Rivers and 389th out of 422 in Nigeria as of 2020.

New Street Additions (2006–2020)

SNDi value
5.77
Rank in Nigeria
335th of 422
Rank in Rivers
12th of 28

Entire Network (Aggregate)

SNDi value
5.38
Rank in Nigeria
389th of 422
Rank in Rivers
19th of 28

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

What about similarly populated cities?

23456<19751976–19901991–20052006–2020SNDi of street additions
23456<19751976–19901991–20052006–2020SNDi of entire street network
Port HarcourtValenciaBoston

In new street additions, Port Harcourt fluctuated in its street-construction patterns, while Valencia built increasingly disconnected streets over time and Boston built increasingly disconnected streets from 1975 through 1991-2005, then improved. For the full street network, though, all three cities follow the same trend.