Cyclists and left turning drivers: a study of infrastructure and behaviour at intersections

Cycling is a legitimate mode of transport for a proportion of the population in Australia. Interactions between drivers and cyclists at intersections are complex, particularly left turn negotiations when a cyclist is travelling straight and a driver intends to turn left. Current understanding of safe and unsafe interactions involving these types of left turn negotiations is limited. This study employed a mixed method investigation into the factors involved in driver-cyclist left turn negotiations including desk-based analysis of police reported cyclist crash data and a cross-sectional observational study using a roadside mounted video camera. Video analysis included observed driver/vehicle and cyclist behaviour across different infrastructure types and implications for road rules. Crash data indicates left turn negotiation incidents are proportionally less severe when compared to all cyclist crashes, gender distributions align with that for work-related bicycle trips, and site traffic control type may influence crash risk. Future studies could extend the methods used across additional sites to gain a representative understanding of the types of road design that maximises safe left turn negotiations between drivers and cyclists.