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81 Analysis tools: Identify intersections Identify the type of - Field survey where TSP would be TSP--conditional or Is an AVL system - Analytical modeling operationally feasible. unconditional. available? - Simulation Compare TSP to other Identify distributed vs. potential preferential centralized TSP Identify the bus treatments at system detection system. intersections or along the corridor Identify the extent of Identify specific signal TSP application system improvements Evaluate the impact of TSP FIGURE 56 TSP decision framework [Source: TCRP Report 118 (5 )]. supplement and not replace TSP along a corridor, to reflect Design and construction/installation of facilities and unique conditions at particular intersections. equipment; Operations monitoring of equipment (mainly related to TSP--setting/adjustment to signal timing plans); Curb Extensions Maintenance of facilities and equipment (TSP, signage, street cleaning/snow plowing, etc.); TCRP A-10A developed a detailed set of questions that Replacement of equipment, including technology up- might be reviewed in making the decision to install a curb grades (TSP); extension at an intersection or a number of these treatments Monitoring of impact on transit operations (use of AVL/ on an urban street (see Table 32). The basic conditions for the APC equipment and/or field surveys); application of a curb extension are: (1) a near-side transit Monitoring of impact on traffic operations (system stop is preferable, (2) at least two traffic lanes are available if detection, field surveys); and the curb extension is to be far side (to allow general traffic to Coordination meetings to review project implementation/ get around a stopped transit vehicle and not block the preced- operations/monitoring issues and strategize on future ing intersection, and (3) there are very high passenger vol- improvements umes at a stop where the added passenger waiting area asso- ciated with a curb extension is critical. Examples of intergovernmental agreements executed between the transit and traffic agencies in King County and Snohomish County, Washington are presented in Appen- INTERGOVERNMENTAL AGREEMENTS dix C. King County's sample Speed and Reliability Partner- ship agreement that relates the provision of added transit Based on the transit and traffic agency responses to the sur- service in a corridor to local agency provision of transit pref- veys conducted in this synthesis, a slight majority of those erential treatments is a novel concept that could have appli- respondents indicated that they have formal intergovern- cability to transit agencies across the United States. mental agreements in place related to the implementation, operations and maintenance, and monitoring of performance of transit preferential treatments. Most of these agreements FURTHER RESEARCH NEEDS relate to TSP. This is an area where more emphasis might be given in the future, with intergovernmental agreement(s) This synthesis includes a literature review of several past integrated into formal comprehensive transit preferential research studies related to transit preferential treatments, and treatment programs. Such agreements could clearly identify incorporates the results of a comprehensive survey of transit transit versus traffic agency responsibility with respect to and traffic agencies. Based on a review of this material, the the following: following added research needs are suggested.

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82 TABLE 32 QUESTIONS TO BE ADDRESSED IN DECIDING ON INSTALLATION OF CURB EXTENSIONS (continued on next page)

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83 TABLE 32 (continued) Source: TCRP Report 65: Evaluation of Bus Bulbs (8). Warrants for Transit Preferential the provision of exclusive bus lanes or limited stop applica- Treatment Application tion with TSP. Conducting some research on this topic could give agencies more information on the application of the The transit agencies responding to the survey associated with most cost-effective strategy for transit preferential treatments this synthesis identified "warrants" for different transit pref- along a corridor. This could include the tradeoffs of using erential treatments, primarily in terms of evaluation criteria simulation versus analytical modeling in conducting such or performance measures--and not specifically numerical assessments. warrants. NCHRP Report 155 presented some numerical warrants for different treatments; however, this report is more than 30 years old and an updated assessment of war- Limited Stop/Stop Consolidation Impacts rants would be a worthy research topic. Little documentation was found related to guidelines for con- solidating transit stops in a corridor to facilitate transit oper- Benefits of Multiple Transit Preferential ations and identifying the specific impact on transit travel Treatment Applications time savings and on-time performance. A further survey of transit agencies to probe their policies related to stop consol- There appears to be little guidance on identifying the incre- idation for different transit services would be desirable, as mental benefits of packaging multiple transit preferential well as selection of a couple of corridors to conduct a "before" treatments in a corridor, such as the impact of adding TSP to and "after" evaluation of stop consolidation application.

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84 Tradeoffs on Intersection-Based Transit with many not having formal intergovernmental agreements Preferential Treatments with respect to planning, design, construction, operations and maintenance, and performance monitoring of treatments. There appears to be little guidance on when to apply different Added study would be helpful to identify the process of intersection transit preferential treatments, in particular when establishing transit preferential treatment needs on a corri- TSP might be provided versus a queue jump lane and signal, dor and regional scale, and identifying alternate implemen- or curb extensions. This study might involve the use of a sim- ulation model to estimate the impacts on bus delay and general tation strategies, including potential funding sources. This traffic operations for these different transit preferential treat- could include an assessment of the costs and impacts of ments under different traffic and transit volume conditions. alternate governmental relationships, and the development of one or more sample agreements, similar to the Speed and Reliability Partnership agreement developed by King Intergovernmental Relationships in Transit County Metro. Preferential Treatment Development Survey results indicated that most transit and traffic agencies do not have formal transit preferential treatment programs,