Towards safe system infrastructure investment on New Zealand roads – a technique for maximising serious trauma savings
The Macro Estimates for Target Setting (METS) modelling technique developed at MUARC has been used extensively to estimate the savings in serious casualties (fatalities and seriously injured) for road safety strategies in a number of Australian states and territories. In this application, the New Zealand Transport Authority (NZTA) sought to focus specifically on exploring opportunities for improved road safety outcomes for the nation's road infrastructure investment programs. METS was adapted to investigate several scenarios involving not only reallocating expenditure among existing programs, but also the introduction of three new "Safe System Transformation" programs. These programs, involving a notional amount of up to NZ$100m of investment per annum, targeted serious casualties at urban intersections, rural intersections, and head-on and run-off-road crashes on rural routes. Between 2007 and 2009, these three categories comprised half of all serious casualties on New Zealand roads. New techniques were developed, consistent with Safe System principles, for maximising serious casualty savings at intersections and along routes, using the comprehensive crash data available from the NZTA. Each of the three scenarios was predicted to prevent between 1000 and 1700 additional serious casualties compared with the "business-as-usual? case over a ten-year period. This paper illustrates the application of the optimisation process for serious run-off-road crashes on rural routes.