Abley was commissioned by Transport for New South Wales (TNSW) to develop a strategy and implementation process for identifying and prioritising road safety improvements on high-risk curves along road corridors in New South Wales.
Rather than simply prioritising individual curves for treatment, entire road corridors were prioritised for curve treatments to ensure consistency from a driver’s perspective. The Abley team used speed modelling tools and crash data to identify high risk curves. A GIS linear referencing technique was then used to establish which corridors would be prioritised for curve investigation and improvement by analysing the crash record and number of high-risk curves on each corridor. Using the tools outlined above, a detailed corridor based analysis was undertaken in the Southern and South West regions of NSW. In addition, a literature review was undertaken to ascertain effective treatments on high risk curves, and a treatment hierarchy established to help identify appropriate curve treatments on corridors prioritised for improvements.
The Treatment Hierarchy helped the TNSW Centre for Road Safety to prioritise corridors and identify treatment strategies to reduce crashes occurring on high risk curves. The process considers both safety risk through GIS analytic techniques and cost constraints through the Treatment Hierarchy. This enabled the Centre for Road Safety NSW target safety spending on projects that would yield the greatest safety benefit.