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3 CHAPTER ONE INTRODUCTION BACKGROUND Public transportation services have traditionally been de- signed to serve concentrated travel patterns that allow for large numbers of people to be conveyed along established routes following set schedules. These services have worked well in densely built-up areas with strongly focused travel patterns, such as commuting to and from downtown areas. For at least the past 50 years, growth patterns, economic trends, and social changes have not favored traditional forms of transit service. Population and jobs have become more spread out. Economic and social changes have led to complicated personal activity patterns that require the most flexible possible personal mobility. Within the last 30 years, increasing social awareness has led to an under- standing that many people, especially older people and people with disabilities, cannot use conventional public transportation and need other options. Among the solutions proposed to help transit adapt to these changes have been multicentered transit networks us- ing timed transfers and demand-responsive services such as personal rapid transit and dial-a-ride. Many proposals have in common attempts to make transit service more flexible, so that it can respond to changing demand; serve more spontaneous, amorphous travel patterns; and accom- modate people who are unable to walk to and from bus stops and transit stations. Multicentered transit networks have been widely adopted, but personal rapid transit has proved expensive and difficult to create, and it has so far seen only very lim- ited application. Experience to date with the dial-a-ride concept has shown that it appears to have inherent limita- tions in efficiency that limit its applications to specialized service for older people and people with disabilities, as well as service to the general public in very small commu- nities. At least since the 1960s, practitioners have proposed services that combine features of conventional service and purely demand-responsive service (Cole 1968; Arrillaga and Mouchahoir 1974). One of the earliest documented experiments is the Merrill-Go-Round in Merrill, Wisconsin (Flusberg 1976; Mergel 1976), which used a âpoint devia- tionâ mode of operation, as defined later in this report, and that is still operating. More recent research continues to propose flexible transit services as part of the toolkit to help transit operators address suburbanization and dis- persed travel patterns (Cervero and Beutler 1999; Urbitran 1999). Researchers have claimed a variety of benefits for flexi- ble transit services, including increasing ridership (Flus- berg 1976; Durvasula et al. 1998), more cost-effective and integrated service for people with disabilities (Multisys- tems Inc. and Crain & Associates 1997), combining the regularity of fixed-route service with the flexibility of de- mand-responsive services (Farwell 1998), serving areas with demand densities too high for door-to-door services but not high enough for fixed-route service (Pratelli 2002), and making transit more attractive to âchoiceâ riders who have another mode of access (Potomac and Rappahannock Transportation Commission 2003). Rosenbloom (1996) in- terviewed 40 transit systems with flexible service and found that most of them had adopted flexible services as a way to remove or reduce the need to provide complemen- tary paratransit mandated by the Americans with Disabili- ties Act (ADA). However, many of those systems were probably not in conformity with the ADA regulations. Much of the literature about demand-responsive and flexible service has assumed that a high degree of automa- tion would be a key element of its operation (Smith 1998; Durvasula and Priya 1999; Loukakos and Blackwelder 2000; Pratelli 2002). One of the key design issues in oper- ating flexible transit is determining how much scheduled operating time needs to be reserved as slack time to ac- commodate demand-responsive service requests. Fu (2002) has shown how this problem can be approached using ad- vanced mathematical simulation methods. SCOPE AND METHODS This synthesis project was conducted to gather information about the experiences of transit operators using flexible transit services, including the following: â¢ Kinds of flexible service in operation; â¢ Ridership markets; â¢ Ridership threshold levels found to make those ser- vices a viable alternative to traditional fixed-route service; â¢ Historical and funding contexts; â¢ Operating procedures and technology; â¢ Design factors and criteria, such as service area, headway, guaranteed stop locations, deviation sched-
4 uling, including âslack time,â and real-time on-board requests; â¢ Costs and cost considerations; â¢ Staff training (e.g., drivers, schedulers, dispatchers, and controllers); â¢ Customer marketing and public information; â¢ Coordination and integration with paratransit service; â¢ Previous successes and failures; and â¢ Barriers and future opportunities. For purposes of this synthesis, âflexible transit servicesâ are considered to include all types of hybrid services that are not pure demand-responsive service (including dial-a- ride and ADA paratransit) or fixed-route service, but that fall somewhere in between those traditional service mod- els. In other words, the services of interest have some es- tablished stop locations and/or some established schedule, combined with some degree of demand-responsive opera- tion. Fixed-route services that allow flag stops (a common method of operation in rural areas and some small cities, and after dark in some larger cities) but that have no other flexible features have not been included. In the preliminary phases of the research, more than 80 transit systems were identified that might be operating some type of flexible service. Sources for identifying these candidate systems included published literature; requests to Internet e-mail discussion groups maintained by APTA and by the TRB Committees on Paratransit and Transit Plan- ning; personal contacts; and website searches. A written survey (Appendix A) was sent to a total of 81 transit sys- tems. Twenty-five systems returned completed question- naires, of which one was determined not to provide flexi- ble service. Appendix B lists the transit systems that responded. The survey responses were supplemented by follow-up interviews with transit agency staff and refer- ences to service descriptions available on transit agency websites. REPORT ORGANIZATION This synthesis begins with an overview of expectations for flexible transit services as revealed by published reports and papers during the past 35 years. â¢ Chapter two provides a classification of flexible tran- sit services that is used for analysis throughout the rest of the report and a picture of the extent to which flexible services are actually used, including how long they have been in operation. â¢ Chapter three describes design decisions that opera- tors have made in their flexible services, including provisions for spontaneous use as in conventional transit, provisions for demand-responsive use, fares, and coordination with conventional services and paratransit services. â¢ Chapter four describes the roles in which transit op- erators have used flexible services as an element of their overall service planning. That chapter also re- views how flexible services have been marketed; per- formance standards, measurement, and experience; and the barriers that transit operators have faced in the past and the opportunities that they see in the fu- ture for flexible services. â¢ Chapter five concerns operational issues, including the allocation of scheduled time between serving fixed stops and demand-responsive service requests, scheduling and dispatching, staff selection and train- ing, and choice of vehicles. â¢ Chapter six presents case studies of five systems, with additional detail about service design, some back- ground and operating results, and lessons learned. The case studies were chosen because of their innovative character, performance, established history, likelihood of continuation, and availability of information. â¢ Chapter seven provides conclusions and suggestions for additional study.