Ryosuke OTA

Evaluation of Traffic Congestion Mitigation Measures Using a Trip Chain-Based Traffic Assignment Model

Teppei KATO

In recent years, the rapid increase in inbound tourism to Japan has intensified overtourism in certain destinations. Traffic congestion and overcrowding not only reduce tourists’ satisfaction but also negatively affect residents’ daily mobility and quality of life. In response, local governments have implemented tourism policies aimed at dispersing visitors as well as transportation measures to improve accessibility. However, these measures are often evaluated separately, and their interactive effects on travel behavior and traffic congestion have not been sufficiently examined within a unified analytical framework.
This study aims to evaluate tourism and transportation policies in an integrated manner and to explore more effective strategies for mitigating overtourism. Focusing on tourists’ multi-destination travel behavior, a traffic assignment model that explicitly incorporates trip chains is developed. Based on this model, user benefits are calculated to assess policy impacts.
Numerical experiments are first conducted on a hypothetical symmetric network to clarify the fundamental mechanisms of each policy. The results indicate that introducing a new tourist attraction improves tourists’ benefits but may induce additional travel demand, thereby reducing residents’ welfare. Capacity expansion of links connected to tourist sites alleviates congestion and improves overall benefits; however, part of this effect may be offset by induced demand. Moreover, combined policies can generate synergistic effects.
The robustness of these findings is then examined using an asymmetric network with uneven population distribution and accessibility conditions. While the basic tendencies remain consistent, differences in location and demand scale influence the magnitude and distribution of policy impacts.
Overall, this study presents an integrated evaluation framework that captures the interaction between tourism and transportation policies, providing practical insights for designing effective overtourism mitigation strategies.