Norristown in context: Street-network sprawl trends

Norristown in context

2.73.64.5<19751976–19901991–20052006–2020SNDi of street additions
2.73.64.5<19751976–19901991–20052006–2020SNDi of entire street network
NorristownPennsylvania (Region)United States (Country)

The chart above shows SNDi trends for new street additions (left panel) and the entire network (right panel), with Norristown plotted against Pennsylvania and United States. While Pennsylvania and United States both peaked in 1991-2005, Norristown's new street additions peaked in 1991-2005. Most recently, Norristown's incremental SNDi fell from 4.7 to 3.12 between 1991-2005 and 2006-2020. In terms of the aggregate network, Norristown ranked 12th out of 16 cities in Pennsylvania and 97th out of 333 in United States as of 2020.

New Street Additions (2006–2020)

SNDi value
3.12
Rank in United States
51st of 333
Rank in Pennsylvania
3rd of 16

Entire Network (Aggregate)

SNDi value
2.62
Rank in United States
97th of 333
Rank in Pennsylvania
12th of 16

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

What about similarly populated cities?

2468<19751976–19901991–20052006–2020SNDi of street additions
2468<19751976–19901991–20052006–2020SNDi of entire street network
NorristownWalikaleHongya

In new street additions, Norristown built increasingly disconnected streets from 1975 through 1991-2005, then improved, while Walikale built increasingly connected streets over time and Hongya fluctuated in its street-construction patterns. For the full network, Norristown and Hongya both became progressively more disconnected, while Walikale became more connected from 1975 through 1976-1990, then grew more sprawly from 1976-1990 onwards.