European cities increasingly implement 30 km/h speed limits across street networks. A new paper aimed to evaluate the effectiveness of such speed limits in Europe. Quantitative methods and qualitative assessments were used to condense research findings. The study examined the impact of city-wide 30 km/h speed limits on safety, the environment, energy consumption, traffic, livability, and health before and after their phased implementation. The systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines.
Data from 40 European cities, including Brussels, Paris, and Zurich, showed that lower speed limits improved road safety by reducing the likelihood and severity of crashes. On average, implementing 30 km/h speed limits led to a 23% reduction in road crashes, a 37% decrease in fatalities, and a 38% drop in injuries.
Environmental benefits included an 18% reduction in emissions, a 2.5 dB decrease in noise pollution, and a 7% reduction in fuel consumption, reflecting enhanced fuel efficiency and a reduced environmental impact. Encouraging walking, cycling, and public transit use can further promote a safer and more environmentally sustainable urban environment.
Unfortunately, the research did not examine the specific impact on public transport, city logistics, and taxis. However, it is noted that in a survey conducted in Bilbao, responders who were initially most resistant to the measures, such as traders, delivery drivers, and taxi drivers, proved to be happy to improve traffic flow and acknowledged that the lower speed limit did not cause them any problems.