To reduce conflicts and ensure safe and comfortable mobility for both pedestrians and cyclists, the development of dedicated bicycle lanes is crucial. However, compared to many European cities, Japanese roads are often narrower, making it challenging to allocate dedicated space for bicycles. Effectively prioritizing the installation of dedicated bicycle lanes requires a deep understanding of real-world street usage patterns. This study provides a quantitative assessment of how spatial separation, operationalized as the installation of dedicated bicycle lanes, affects cyclists’ safety and rideability, based on image analysis. The analysis utilizes camera data collected in Fukuyama City, focusing on dedicated bicycle lane before and after installation. The results indicate that while the introduction of dedicated lanes reduced the available space and subsequently decreased bicycle speeds (i.e., did not improve rideability), the physical separation between bicycle and pedestrian areas significantly reduced interactions between pedestrian and bicycle, leading to enhanced safety. Therefore, although no improvement in rideability was observed, the study suggests that the development of dedicated bicycle lanes has a positive impact on safety and supports their strategic implementation.
Fujiwara et al. (Sat,) studied this question.