Transformation to a trunk and feeder network: effects on passenger flows, travel times and reliability

We evaluate a large scale network change in Amsterdam, the Netherlands, where a regional network of many direct bus lines is replaced by a new metro line as a trunk line and buses serving as feeder lines. For the analysis we use realized trip times from automated vehicle location data and ridership details from smart card data. In the new network, we observe a strong shift to the new transfer stations. On the other hand, stops and lines keeping their direct connection in the new feeder network are used more than other stops and lines. From northern direction, the leg on the faster trunk line is too short to compensate for the additional transfer, leading to a slight increase in travel time. From the south, travel time has become shorter: a longer leg is travelled on the new metro line. Finally, all new feeder lines operate more reliably than the former direct lines. These findings can help guide ex-ante evaluations for other networks considering transition to a trunk and feeder system.