Increasing Schedule Reliability on the S-Bahn in Zurich, Switzerland: Computer Analysis and Simulation

Document Type

Journal Article

Publication Date


Subject Area

operations - traffic, operations - reliability, infrastructure - station, infrastructure - stop, planning - methods, land use - planning, economics - appraisal/evaluation, mode - rail


Zurich (Switzerland), Train traffic, Traffic delay, Strategies, Strategic planning, Stops, Stopping, Stopped time delay, Statistical methods, Statistical analysis, Simulation, Schedules, Schedule maintenance, S-Bahn (Stadtschnellbahn), Reliability, Regional railroads, Recommendations, Railway engineering, Railroad traffic, Railroad stations, Railroad engineering, Railroad commuter service, Priorities, Passengers, Objectives, Mathematical statistics, Infrastructure, Implementation, Goals, Evaluation, Dwell time, Dispatching, Computer simulation, Commuter rail, Boarding and alighting


Delays on the regional rail system in Zurich, Switzerland, had risen to unacceptable levels by 2003 because of increasing ridership and more frequent service. The research goal was to identify the causes of delay, develop measures to reduce delays, evaluate these measures, and make recommendations. A combination of engineering and computerized statistical analysis was used to identify and evaluate delays. The main causes of delay were increased station dwell time (for passenger boarding and alighting), trains entering the core network late, and suboptimal track and platform dispatching. Measures for reducing delays were developed and tested by simulation. Recommended measures included systematic revision of dwell times throughout the network, new stopping patterns, new dispatching techniques, and development of a prioritized infrastructure program. Several recommendations were implemented in the December 2004 schedule change and have helped reduce delay. The study’s main recommendation is that the identified measures be implemented systematically and continuously.