An evaluation of the 50km/h default speed limit in regional Queensland

Monash University Accident Research Centre - Report #265 [2007]

Authors: Hosking, S., Newstead, S., Hoareau, E. & Delaney, A.

Abstract:

The 50km/h default speed limit was introduced on local roads in regional Queensland in February 2003. Following a three-month amnesty period, full enforcement of the 50km/h speed limit commenced in May 2003. The objectives of this report were to evaluate the effect of the 50km/h default speed limit on crash frequencies and vehicle speeds in regional Queensland.
This evaluation has found strong evidence of significant crash reductions associated with implementation of the 50km/h default speed limit in regional Queensland. Crash reductions were estimated both in the amnesty period immediately after implementation and in the subsequent period during which the new speed limit was fully enforced. The evaluation covered the period until the end of May 2004. In the period of full enforcement, the analyses found statistically significant crash reductions of 13.5% for all crashes reported to police. Greater reductions were estimated in higher severity crashes with a reduction of 24.9% estimated for serious casualty crashes (crashes involving death or hospitalisation) and 19.3% for fatal, hospitalisation and medical attention severity crashes combined. Estimated percentage crash reductions in the full enforcement period translated to an estimated saving of 9 casualty crashes, 5 serious casualty crashes and 14 crashes of all severity levels per month

The analyses also found that the 50km/h default speed limit was associated with significant reductions in crashes that involved younger drivers both during the amnesty and full enforcement periods. It also estimated statistically significant reductions in speed related crashes that occurred primarily during the amnesty period. Analysis of speed survey data associated with the program implementation indicates that the reported crash reductions were associated with a reduction in vehicle speeds above 60km/h on roads that became 50km/h subsequent to the default limit introduction.

It was concluded that the 50km/h default speed limit was an effective program in reducing crashes in regional Queensland.

Sponsoring organisation - Queensland Department of Transport