Poissy in context: Street-network sprawl trends

Poissy in context

2.43.244.8<19751976–19901991–20052006–2020SNDi of street additions
2.43.244.8<19751976–19901991–20052006–2020SNDi of entire street network
PoissyIle-de-France (Region)France (Country)

The chart above shows SNDi trends for new street additions (left panel) and the entire network (right panel), with Poissy plotted against Île-de-France and France. While Île-de-France and France both peaked in 1991-2005, Poissy's new street additions peaked in 1991-2005. Most recently, Poissy's incremental SNDi fell from 4.96 to 3.2 between 1991-2005 and 2006-2020. In terms of the aggregate network, Poissy ranked 8th out of 8 cities in Île-de-France and 66th out of 73 in France as of 2020.

New Street Additions (2006–2020)

SNDi value
3.2
Rank in France
37th of 73
Rank in Île-de-France
6th of 8

Entire Network (Aggregate)

SNDi value
3.42
Rank in France
66th of 73
Rank in Île-de-France
8th of 8

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
PoissyGaighatBeja

While Gaighat and Béja both fluctuated in its street-construction patterns, Poissy built increasingly disconnected streets from 1975 through 1991-2005, then improved in new street additions. For the full network, Poissy grew more disconnected from 1975 through 1991-2005, then improved, while Gaighat fluctuated in connectivity and Béja became progressively more disconnected.