Niihama in context: Street-network sprawl trends

Niihama in context

22.533.5<19751976–19901991–20052006–2020SNDi of street additions
22.533.5<19751976–19901991–20052006–2020SNDi of entire street network
NiihamaEhime (Region)Japan (Country)

The chart above shows SNDi trends for new street additions (left panel) and the entire network (right panel), with Niihama plotted against Ehime and Japan. The SNDi of new construction in Niihama rose steadily, compared to Ehime which followed a zig-zag trend with an overall increase and Japan which followed a zig-zag trend with an overall increase. Most recently, Niihama's incremental SNDi rose from 3.28 to 3.77 between 1991-2005 and 2006-2020. In terms of the aggregate network, Niihama ranked 3rd out of 4 cities in Ehime and 105th out of 135 in Japan as of 2020.

New Street Additions (2006–2020)

SNDi value
3.77
Rank in Japan
109th of 135
Rank in Ehime
3rd of 4

Entire Network (Aggregate)

SNDi value
2.73
Rank in Japan
105th of 135
Rank in Ehime
3rd of 4

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
NiihamaLogronoHuddersfield

While Logroño and Huddersfield both built increasingly disconnected streets from 1975 through 1991-2005, then improved, Niihama built increasingly disconnected streets over time in new street additions. For the full street network, though, all three cities follow the same trend. Niihama and Huddersfield have been growing further apart in their street-network character since 1975.