Isahaya in context: Street-network sprawl trends

Isahaya in context

2.433.6<19751976–19901991–20052006–2020SNDi of street additions
2.433.6<19751976–19901991–20052006–2020SNDi of entire street network
IsahayaNaoasaki (Region)Japan (Country)

The chart above shows SNDi trends for new street additions (left panel) and the entire network (right panel), with Isahaya plotted against Naoasaki and Japan. All three follow the same trend in new construction, suggesting a shared regional pattern of development. Most recently, Isahaya's incremental SNDi rose from 3.21 to 3.4 between 1991-2005 and 2006-2020. In terms of the aggregate network, Isahaya ranked 2nd out of 4 cities in Naoasaki and 89th out of 135 in Japan as of 2020.

New Street Additions (2006–2020)

SNDi value
3.4
Rank in Japan
100th of 135
Rank in Naoasaki
2nd of 4

Entire Network (Aggregate)

SNDi value
2.55
Rank in Japan
89th of 135
Rank in Naoasaki
2nd of 4

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

What about similarly populated cities?

1.42.12.83.5<19751976–19901991–20052006–2020SNDi of street additions
1.42.12.83.5<19751976–19901991–20052006–2020SNDi of entire street network
IsahayaWorcesterJingang

In new street additions, Isahaya fluctuated in its street-construction patterns, while Worcester built increasingly disconnected streets from 1975 through 1991-2005, then improved and Jingang built increasingly disconnected streets from 1975 through 1976-1990, then improved. For the full network, Isahaya and Worcester both became progressively more disconnected, while Jingang grew more disconnected from 1975 through 1976-1990, then improved. Isahaya and Worcester have been converging in their street-network character since 1975.