Evaluation of the Effectiveness of Connection Protection in Improving Successful Light Rail-to-Bus Transfers

Document Type

Journal Article

Publication Date


Subject Area

infrastructure - vehicle, infrastructure - interchange/transfer, economics - appraisal/evaluation, mode - bus, mode - rail, mode - tram/light rail


Utah Transit Authority, Transit vehicle operations, Transfers, Public opinion, Light rail transit, Intracity bus transportation, Evaluation and assessment, Connection protection system (Transit), Bus transit


The quantitative evaluation results of the nation’s first light rail–to-bus connection protection (CP) system implemented by the Utah Transit Authority are presented. The CP system was designed to improve the reliability of transfers from the higher-frequency light rail TRAX trains to the lower-frequency bus services. The CP system examines the estimated arrival time of TRAX trains for the next three stations and issues a “hold at {station name} until {time}” message to buses waiting at the connecting rail stations, via the buses’ onboard mobile data terminals, if the lateness of trains is within a predetermined threshold (e.g., 3 min). The evaluation consisted of a quantitative analysis of the successful rail-to-bus connections with an analysis of the rail and bus operations data and a qualitative assessment of the perspectives and opinions of users based on individual experience (both riders and bus operators). The focus was the quantitative analysis that employed an unmatched with-and-without experimental design. Overall, the analysis results showed that CP did significantly increase the percentage of successful train-to-bus connections. Train riders meeting a bus trip when CP was active and a “hold until” message was issued to the bus operator were between 3.1 and 3.9 times more likely to have had a successful connection than were train riders meeting the same bus trips when CP was inactive, depending on the wait time assumption for a successful connection to take place.