Regional Rail: Scheduling for Connections

As the extent of North American commuter rail systems increases, interest increases in developing new services to connect with existing and established passenger rail lines. Some new systems under consideration rely on timed transfers between low-frequency routes so that some or all passengers may reach their ultimate destinations. The paper summarizes six North American services that rely on connections and planning reports for two potential new services. It draws general observations and recommendations for the design of other new services and suggests general findings and guidelines for the design and operation of the commuter rail transfer operations. First, most branch-line connecting services tend to offer the greatest economic utility as service supplements during off-peak periods. Second, attractive and economical connecting services are easier to schedule and manage when the branch is very short. Third, it is difficult for a single consist (train set) to provide optimal connections in both directions. Fourth, when trade-offs between convenient inbound and outbound connections must be considered, schedulers nearly always favor the quality of the outbound connection over that of the inbound connection. Fifth, the scheduling of evening outbound connections often entails a load-and-go type of operating regime. Finally, the quality of branch-line connecting services is affected by the reliability of the main-line service.