Simulation-Based Methodology for Improving Central Ottawa Transitway Performance

In North America and elsewhere around the world, there is a growing interest in bus rapid transit systems (BRTs) for serving the travel needs of middle size cities. Ottawa’s bus rapid transit model is well recognized for attracting and keeping riders in spite of competition from the private automobile mode. This specially designed facility enables OC Transpo, Ottawa’s transit agency, to provide fast and reliable bus service. However, starting 2003, there was a growing concern among planners and transportation engineers in the City of Ottawa that bus travel time in the eastbound direction on the Central Transitway was showing a significant increase. It was recognized that field observations are useful for the identification of causes and patterns of delays in bus operations that increase travel time on the Slater eastbound bus corridor in Ottawa; a scientific method had to be used for a detailed investigation of problems and development of solutions. Over a three- month period transit operations were observed in the field and compared with operations on the westbound Albert corridor. After some causes were identified, the Central Transitway within the road network in downtown Ottawa was also modeled and possible scenarios were examined using the microscopic simulation tool NETSIM. Based on the results derived from the field and from simulation, conclusions and recommendations were drawn to improve Central Transitway performance and reduce bus travel time. The results of this research project were brought to the attention of the OC Transpo and City of Ottawa engineers and planners. According to OC Transpo's technical personnel, the implementation of recommendations helped to improve the eastbound corridor performance. This paper consists of five parts. Part 1 introduces the project background, objectives and methodology. In part two, literature is reviewed on transit operations on bus lanes, bus operating strategies, and headway based reliability control. Part three describes the study area, data collection and analysis of transit operations on the Central Transitway. In part four, the modeling and simulation of the Central Transitway is covered and highlights of results are presented. Finally, in part five conclusions and recommendations are noted.