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3 CHAPTER ONE INTRODUCTION BACKGROUND Methodology Transit preferential treatments are not new, having been This report focused on three components: around for about 70 years for buses and longer for on-street rail systems. However, in recent years there has been increasing 1. A review of past literature that addressed transit pref- interest in the development of preferential treatments where erential treatments, both in terms of their features and bus or rail vehicles operate in a mixed-traffic environment, in application warrants, but also their impact on both tran- particular on arterial streets in urban and suburban areas. sit and general traffic operations in different cities across Most bus routes, outside of exclusive busway applications, North America. operate on streets in the general traffic flow alongside general 2. A representative survey of transit agencies that operate traffic. Streetcar lines and many light rail systems also operate streetcar/light rail and/or bus service on city streets, and on streets with general traffic. The inherent congestion on many a parallel survey of traffic engineering jurisdictions that streets, particularly during peak periods, often results in sub- work with transit agencies to implement transit prefer- stantial delays to transit operation that increase travel time ential treatments. and degrade on-time performance. In certain situations this 3. A review of specific cities where more extensive, orga- can lead to the requirement for added transit vehicles (and thus nized transit preferential programs have been developed, added capital and operating cost) to provide the same service and specific information about how these came about frequency. and the successful partnerships involved. The implementation of new bus rapid transit (BRT) systems The literature review (a total of 23 documents were has renewed interest in preferential treatments, critical to keep- reviewed) was intended to obtain added documentation ing the "rapid" in such services. of transit preferential treatments beyond the three current sources, where some organized presentation of overall pre- Transit preferential (or priority) treatments range from ferential treatments has existed in recent years: TCRP Report exclusive transitways and transit lanes applied along certain 100: Transit Capacity and Quality of Service Manual (3), roadway segments to spot improvements typically applied at TCRP Report 90: Bus Rapid Transit Volume 2: Implementa- intersections, such as transit signal priority (TSP), queue jump tion Guidelines (4), and TCRP Report 118: Bus Rapid Transit signals, bus bypass lanes, and curb extensions (also known as Practitioner's Guide (5). Through the transit agency survey bulbouts). conducted, added documentation of transit preferential treat- ment programs and assessments were obtained. SCOPE The transit agency survey was designed to obtain insights on Objective the types of preferential treatments that were implemented in their service areas, under what conditions, and what the impacts Although there have been several research projects and project were on transit operations. Also of interest were the partner- studies in certain urban areas that have addressed transit prefer- ships in place with the traffic engineering jurisdictions in their ential treatments in mixed-traffic environments, including war- area to plan, design, implement, operate, and maintain treat- rants for their application and costs and impacts of different ments. The following information was sought: treatments, most notably NCHRP Reports 143 and 155 (1,2) from the 1970s, there has not been a recent document that Type and location of different treatments; focuses just on this subject. The TCRP J-7/SA-22 project was Characteristics of transit service using preferential intended to provide such a document. The initial problem state- treatments--peak versus off-peak transit volumes and ment for this project was developed by the TRB Committee on operating periods of treatments; Transit Capacity and Quality of Service, which recognized the Characteristics of streets where treatments are located-- importance that transit preferential treatments could provide traffic volumes and level of service; with respect to increasing capacity and improving quality of Costs of different treatments--capital and operations and service for transit operations in mixed-traffic environments. maintenance (O&M);