Petaluma in context: Street-network sprawl trends

Petaluma in context

33.64.24.8<19751976–19901991–20052006–2020SNDi of street additions
33.64.24.8<19751976–19901991–20052006–2020SNDi of entire street network
PetalumaCalifornia (Region)United States (Country)

The chart above shows SNDi trends for new street additions (left panel) and the entire network (right panel), with Petaluma plotted against California and United States. The SNDi of new construction in Petaluma peaked in 1976-1990, compared to California which peaked in 1976-1990 and United States which peaked in 1991-2005. Most recently, Petaluma's incremental SNDi fell from 3.95 to 3.23 between 1991-2005 and 2006-2020. In terms of the aggregate network, Petaluma ranked 23rd out of 60 cities in California and 194th out of 333 in United States as of 2020.

New Street Additions (2006–2020)

SNDi value
3.23
Rank in United States
59th of 333
Rank in California
6th of 60

Entire Network (Aggregate)

SNDi value
3.46
Rank in United States
194th of 333
Rank in California
23rd of 60

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
PetalumaAmpanaKenar Fatehpur

In new street additions, Petaluma built increasingly disconnected streets from 1975 through 1976-1990, then improved, while Ampana built increasingly disconnected streets over time and Kenar Fatehpur built increasingly connected streets from 1975 through 1976-1990, then shifted to more disconnected patterns. For the full network, Petaluma grew more disconnected from 1975 through 1991-2005, then improved, while Ampana became progressively more disconnected and Kenar Fatehpur became more connected from 1975 through 1991-2005, then grew more sprawly from 1991-2005 onwards. Notably, Petaluma had a more sprawly network than Ampana in 1975 but the two have since reversed their relative ranking.