Model for Estimating Increased Ridership Caused by Integration of Two Urban Transit Modes: Case Study of Metro and Bus-Minibus Transit Systems, Istanbul, Turkey


Darcin Akin

Document Type

Journal Article

Publication Date


Subject Area

operations - capacity, planning - integration, economics - operating costs, place - urban, mode - bus, mode - rail, mode - mass transit, mode - subway/metro, mode - subway/metro


Underground railways, Transit capacity, Transit, Subways, Ridership, Public transit, Patronage (Transit ridership), Operating costs, Minibuses, Miniature buses, Metropolitan areas, Mass transit, Local transit, Istanbul (Turkey), Intracity bus transportation, Intermodal transportation, Intermodal systems, Integrated systems, Integrated control systems, Cost of operation, Conurbations, Case studies, Bus transit, Before and after studies


A simple, practical tool based on integration (basically, shortening) of competing bus and minibus transit services is provided for estimating increased ridership on metro lines. A simple model is developed to estimate the increased ridership in the metro line of Istanbul, Turkey (7.9 km long and being extended), caused by integration with bus and minibus transit lines, and the benefits related to the intermodal integration are presented. To estimate the effectiveness of the integration action, ridership information in all modes before and after the integration was gathered and analyzed. It was found that the ridership-over-capacity (RoC) ratio in the metro lines was quite low (0.28) before the integration. On December 24, 2001, a partial integration was deployed by the bus operator of the metropolitan city when 11 bus and three minibus routes were integrated to the metro, which yielded significant increase in RoC (56%). The study also considered possible options for the development of a full intermodal plan. In this regard, existing bus and minibus transit lines were examined, and 33 bus and three minibus routes were recommended for integration. It was found that such integration would increase RoC from 0.28 to 0.76 without any significant increase in operating cost. Also, the city and private bus and minibus operators would save an estimated of $4.8 million a year from cuts in operating these services along the metro route. It was also estimated that the integration would lower the amount of bus traffic in downtown Taksim and Mecidiyeköy by approximately 25% and 38%, respectively.