Highland Park · lowered 14 July 2022, raised again 17 March 2025
Before
60 km/h
until 14 July 2022
Lower limit
50 km/h
14 July 2022 to 17 March 2025
Raised again
60 km/h
from 17 March 2025
Where the crashes happened
The blue line is the official Auckland Transport speed-change geometry for this section. Each dot is a crash that CAS places on the treated road; colours show which speed-limit period it fell in. Larger red-ringed dots are crashes in which someone died or was seriously injured.
BeforeDuring lower limitAfter raisedDeath or serious injury
What the monthly record shows
Adjusted for Auckland-wide traffic trends, the observed crash rate was 221% higher while the lower limit applied (compared with before), and 18% higher after the limit went back up (compared with the lower-limit period). Single-road counts are noisy, so read this alongside the pooled estimate on the corridor results page.
Measure
Before (54 mo)
Lower limit (31 mo)
Raised (13 mo)
All crashes
1
2
1
Injury crashes
0
1
0
Death or serious injury crashes
0
0
0
Fatal crashes
0
0
0
Crashes per month
0.02
0.06
0.08
Crashes per million vehicle-days*
0.04
0.13
0.15
*Traffic exposure uses this road’s baseline daily traffic trended by the Auckland-wide TMS fixed-site index.
This road’s own model estimates
A segmented Poisson time-series model fitted to this road alone, with terms for the underlying trend and for level changes at the lowering and the raising. Confidence intervals on a single road are wide; the pooled 24-corridor models are the headline evidence.
All crashes · while lower limit applied
Too few crashesfor a road-level model; this road still contributes to the pooled estimate
All crashes · after limit raised
Too few crashesfor a road-level model; this road still contributes to the pooled estimate
Injury crashes · while lower limit applied
Too few crashesfor a road-level model; this road still contributes to the pooled estimate
Injury crashes · after limit raised
Too few crashesfor a road-level model; this road still contributes to the pooled estimate
Crash records are complete to 30 April 2026 (later months are still filling in), so the after-raising period is still short. Estimates for this single road will firm up as more months accumulate; the full method, sensitivity checks and audit files are on the main report page.