New White Paper Explores Safer Left-Turn Treatments at Signalised Intersections

ViaStrada has just released a white paper examining the safety and operational implications of different left-turn treatments at signalised intersections, with a particular focus on balancing the needs of people walking, cycling and driving. The paper will be presented at the 2026 SNUG workshop, providing an opportunity for practitioners to discuss one of the most debated topics in intersection design.

Signalised intersections are among the most complex locations in the transport network, where competing movements and differing user needs must be carefully managed. Left-turn movements can create particular challenges, introducing potential conflicts between motor vehicles and vulnerable road users while also affecting intersection efficiency and network performance. The choice of left-turn treatment can therefore have significant implications for both safety and accessibility.

The white paper explores a range of left-turn treatment options and examines where each may be appropriate. It considers how design decisions influence safety outcomes, user behaviour, level of service, and the overall operation of an intersection. Particular attention is given to the interaction between turning vehicles and people walking or cycling, recognising the increasing emphasis on creating transport networks that are safe and accessible for all users.

Drawing on national and international practice, the paper discusses the advantages and limitations of different approaches and highlights the importance of selecting treatments that are appropriate to the surrounding context. Rather than promoting a one-size-fits-all solution, the research emphasises the need for evidence-based decision-making that reflects local conditions, user needs, and network objectives.

The publication builds on ViaStrada's longstanding involvement in active transport planning, intersection design, road safety, and the development of national transport guidance. It contributes to an ongoing industry conversation about how transport professionals can best achieve safer, more efficient intersections while supporting mode shift and improved accessibility.

The white paper is available to download from the ViaStrada website: Left-turn treatments at signalised intersections.