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17 CHAPTER THREE LITERATURE REVIEW Several studies and research efforts have been completed the time, this corresponded to an operating cost savings describing the application of different transit preferential treat- of $25,000 per year to the Chicago Transit Authority. ments in urban areas in North America. This includes various 2. The contraflow bus lanes on 2nd and 3rd Streets in TCRP reports, reports documenting studies conducted and Louisville (each 1.5 miles in length) reduced travel plans developed for transit agencies, and original research. A times by about 25%. total of 20 documents were reviewed in this synthesis. Brief 3. The Madison Avenue bus lanes in New York City summaries of the content and major findings from these differ- between 86th and 135th Streets reduced midday bus ent reports are presented in this chapter. The review is grouped travel times from 11 to 6.5 min. by type of transit preferential treatment. The report identified a minimum of 60 transit vehicles per peak hour using an exclusive bus lane to justify its designation. GENERAL Also the number of transit riders using transit vehicles in an NCHRP Report 143: Bus Use of Highways-- exclusive lane should equal or exceed 1.5 times the num- State of the Art, 1973 (1) ber of drivers and passengers carried by other vehicles in a single lane during the peak hour. From the standpoint of lane This report was the first comprehensive documentation of enforcement, the report indicated 40 to 60 buses per hour bus operations and priority treatments on urban freeways and should use an exclusive lane (resulting in about one bus in arterial streets in the United States and internationally as of each block at any time on an urban street). the early 1970s. More than 115 different concurrent-flow, curb side bus lane applications and 13 contraflow lane appli- NCHRP Report 155: Bus Use of Highways: cations in the United States and Canada were identified, with Planning and Design Guidelines, 1975 (2) respect to their operating characteristics and signing and pavement markings provided. Another 86 concurrent-flow This report built on NCHRP Report 143 in presenting planning and 37 contraflow bus lane applications in other countries and design guidelines for bus operations and priority treat- (particularly Great Britain, France, and Spain) were also ments on highways. This included for the first time pre- profiled. senting a set of warrants for the application of different bus priority treatments. The underlying principle in identifying In several cases, benefits to bus riders and motorists asso- warrants for priority treatments is whether an exclusive bus ciated with bus lane applications were identified. At the time, lane or other priority treatment would potentially benefit more most systematic measurements of bus lane effectiveness were transit riders than if the treatment were not provided and limited to studies in European cities. The benefits associated added general traffic capacity were available. with bus lanes were related to "bus service dependability." There was no conclusive evidence at the time that there were Suggested values in peak-hour (one-way) bus volumes for transit ridership gains specifically associated with transit pri- exclusive bus lane facilities on arterials were identified as ority treatments or of bus operators being able to reduce the follows: number of buses in service as a result of increased bus speeds and operating effectiveness. However, studies did show mod- Curb bus lanes--within central business district (CBD)-- est time savings associated with bus lane application, with 2030. generally the larger the treatment the greater the benefit. In Curb bus lanes--outside CBD--3040. certain U.S. cities, travel time savings were found to permit Median bus lanes/transitway--6090. reductions in number of buses operating along specific routes. Contraflow bus lanes--extended length--4060. Contraflow bus lanes--short segment--2030. Reported benefits of bus lanes in the United States included the following: These warrants reflect design-year conditions, with exist- ing conditions identified to be at least 75% of these volumes. 1. The bus lane on Washington Street in Chicago (2 miles Contraflow bus lane application was identified to be depen- in length) saved one bus run during peak periods. At dent on a significant directional imbalance of traffic volumes

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18 or application on a one-way street. Where arterial bus vol- The information in this document served as an input into umes of less than 60 per hour are present, the report identi- NCHRP Report 155. fied taxis being able to use designated bus lanes. TCRP Report 118: Bus Rapid Transit Warrants were also identified for bus "preemption" (10 to Practitioner's Guide, 2007 (5 ) 15 buses per peak hour) and special bus signal provisions (5 to 10 buses per peak hour). This report summarizes research to assess the costs and impacts of different BRT components, including a variety of transit A broad set of planning and design guidelines were iden- preferential treatments. Treatments along urban streets, includ- tified related to different bus priority treatments. Some of the ing exclusive bus lanes, TSP, queue jump/bypass lanes, and more pertinent guidelines included: curb extensions, are addressed. For each type of treatment, the following information is provided: The prohibition of curb parking, at least during peak hours, should be a requirement to establishing bus lanes. Basic description, This results in overall increased street capacity, reduces Scale of application (relative size, extent of treatment), delays and marginal friction associated with parking Conditions of application (physical environment, maneuvers, and allows buses easier access to stops. warrants), Bus routes should be restructured as needed to make full Selected typical examples, use of exclusive lanes or transitways. Estimated costs, Bus priority should reduce both mean and the variance in Likely impacts (on bus travel time, service reliability, bus travel time. A 10% to 15% decrease in bus running operating costs, general traffic), and times in a bus priority area was identified as a desirable Analysis tools. objective. An extended application of bus lanes in a corridor is The report also identifies a "bottom-up" approach to rider- required before bus speeds can increase significantly to ship estimation for BRT in a corridor that accounts for travel produce a significant operating cost savings and/or have time savings associated with transit preferential treatments an impact on transit ridership. and other factors. The report also presents examples of how to assess ridership, and the costs and impacts of different BRT Bus lanes should recognize the service needs of adja- scenarios, including four related to the packaging of different cent land uses, including truck deliveries and passenger transit preferential treatments: drop-off/pickup needs. Bus lanes should be provided wherever possible with- 1. At-grade busway with median busway, out reducing the lanes available to through traffic in the 2. Bus lanes and TSP, prevailing direction of general traffic. 3. Bus lanes only, Effective enforcement of bus lanes is essential. 4. TSP only. Roadway plan and cross-section diagrams for different bus lane treatments were identified in the report, with guide- TCRP Report 90: Bus Rapid Transit--Volume 1: lines related to bus stop placement and signing and pavement Case Studies in Bus Rapid Transit, 2003 (9) markings. This report describes the range of BRT applications and pro- vides planning and implementation background through the Guidelines were also identified for bus priority treatments in assessment of 26 BRT projects throughout North America, mixed traffic (identified in the report where buses share a lane Australia, Europe, and South America,. with general traffic--in particular TSP, special turn phases, and curb extensions). The following conditions were identified A common thread throughout all the case studies that to warrant such treatments: was the main reason for implementing BRT systems rather than rail were their lower development costs and greater Corridor capacity is extremely limited by topographical operating flexibility (p. 2). or other constraints. Only one or two continuous streets exist in a corridor. The evaluated performance of each BRT system varied There are fewer than 20 buses in the peak direction in because of the differing configurations of each system. The the peak hour. case studies measured performance by the number of passen- Allocating an exclusive lane for buses would reduce gers carried, travel speeds, and land development changes. total corridor capacity to general traffic to an unaccept- Basically, ridership increases on BRT systems were sited to able level, particularly if oversaturated conditions were be attributable to expanded service, reduced travel times, to arise. improved identity, and population growth. BRT systems Roadway widening is not feasible. within exclusive ROW saw the most benefit. However, in

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19 general, non-exclusive BRT systems save about 1 to 2 min "Bus Semi-Rapid Transit Mode Development per mile and exclusive BRT systems save about 2 to 3 min per and Evaluation," Journal of Public Transportation, Vol. 5, No. 2, 2002, pp. 7195 (11) mile when compared with pre-BRT conditions (p. 6). Fur- ther, the land development benefits experience around BRT Upgrading from mixed-traffic bus service to priority treatment systems were similar to those experienced with rail transit at intersections and/or providing buses in exclusive ROWs are investments. cost-effective methods to increasing transit usage. Further- more, the upgrading or introduction of BRT in exclusive The case studies revealed key lessons learned (p. 7): ROWs should have an overall benefit to other bus and rail lines. According to this report, there are three categories of Early and continuous community support from elected transit ROWs: leaders and citizens is essential. It is important that state, regional, and local agencies 1. ROW category C--urban streets with mixed traffic; work together in planning, designing, and implement- 2. ROW category B--partially separated from traffic with ing BRT. at-grade intersection crossings; and Incremental development of BRT will often be desirable. 3. ROW category A--fully controlled and used exclu- Parking facilities should often complement, not under- sively by transit vehicles. cut, BRT. BRT and land use planning in station areas should be The concept of bus semi-rapid transit was introduced in integrated as early as possible. the 1970s, and has since gone through development that has BRT should serve demonstrated transit markets. met success and obstacles. Successes include its introduction It is essential to match markets with ROWs. as a system concept, running on exclusive lanes and busways, The key attributes of rail transit should be transferred the definition through use of differentiating bus design, and to BRT, whenever possible. applications of Intelligent Transportation Systems (ITS). Set- BRT should be rapid. backs to learn from are the combination of transit with HOV Separate ROWs can enhance speed, reliability, safety, lanes because of the congestion and degradation of service; and identity. bus lanes on streets have experienced the same degradation Vehicle design, station design, and fare collection pro- of service as HOV lanes because the lack of separation offers cedures should be well coordinated. ease of introducing non-transit vehicles to the lane; and the Coordinated traffic engineering and transit service plan- dilution or elimination of priority measures that, again, degrade ning is essential for BRT system design. the performance of the transit system. BRT services should be keyed to markets. The individual systems of the family have service over- Bus Rapid Transit Options for lap that builds off of each other to provide a balanced trans- Densely Developed Areas, 1975 (10) portation system. The successful application of bus semi-rapid transit includes "corridors with many overlapping bus lines; This document provides guidelines for establishing BRT in streets and avenues where separated bus lanes can be intro- densely developed areas without freeways. It includes an duced; and political and civic support for transit in traffic reg- extensive discussion of the application of on-street bus lanes ulations are sufficiently strong that the bus priority measures (curb lanes versus median lanes, concurrent-flow versus con- can be introduced and maintained" (p. 93). traflow), including planning and design guidelines. Specific conditions of application in CBD and non-CBD areas are iden- tified, including peak hour bus volume warrants and estimated "Toward a Systems Level Approach to Sustainable Urban Arterial Revitalization: travel time savings. Travel time savings ranging from 0.4 to A Case Study of San Pablo Avenue," TRB 2006 (12 ) 11.4 min per mile were identified associated with bus lane applications in 12 North American and eight European cities. A sustainable corridor implies "developing a system that is The impact of stop spacing on bus travel time savings and thus economically viable, environmentally friendly, and equitable the impact of limited stop provision is also assessed. across income and racial spectrums, now and in the future" (p. 3). Principles of urban arterial revitalization and redevel- TCRP Report 100: Transit Capacity and Quality opment can be achieved through land use and transportation of Service Manual, 2nd ed., 2003 (3) coordination, multimodal transportation operations, and street design within decision-making processes that rely on com- This document presents a comprehensive overview of the tran- munity involvement. Applying these principles to San Pablo sit capacity and operating characteristics of different transit Avenue in San Francisco, California, provides insight on how modes. Included in the report is information about bus oper- to encourage sustainable urban arterial revitalization. ations on urban streets, including travel time impacts associ- ated with different transit preferential treatments, and clear- San Pablo Avenue operates seven bus routes along at least ance times associated with bus zone areas. part of the segment and during peak periods there are about

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20 20 buses per hour. The need to integrate land use and trans- and facility improvements. The authors created a series of portation planning along this corridor is essential to achieving worksheets that list potential improvements that can be applied the sustainable characteristics described. The study included to, for example, a corridor, bus stop, or intersection. The work- an evaluation of the existing impediments to development sheets are intended to be used to determine if a certain loca- and recommends improvements to the Oakland city code to tion meets the thresholds to warrant the improvement(s). If it alleviate land-use issues in context of the existing transporta- is determined that all the thresholds are met, then the improve- tion system. Another factor recommended to encourage revi- ments for the corridor are weighted and summed for all evalu- talization is sustainable street design that increases transit use ated corridors; the totals for the corridors provide prioritization through improvement of pedestrian access to transit stops and of the corridors for needed improvement. enhanced pedestrian amenities at stops. Also addressed is the calming of high-speed traffic, the implementation of priority The application of this tool to HART's TECs was found treatments for transit to reduce the impacts of congestion, and to be "a technically sound, flexible, and objective evaluation the optimization of signal timing for transit vehicles. methodology for prioritizing transit improvements and can serve as the foundation for subsequent policy discussions and decision-making" that can be applied to the planning- "Characteristics of Bus Rapid Transit Projects: level evaluation and prioritization of corridors in any com- An Overview," Journal of Public Transportation, munity (p. 9). Vol. 5, No. 2, 2002, pp. 3146 (13 ) BRT has been implemented in numerous cities throughout TCRP Report 17: Integration of Light Rail Transit North America. This article provides a review of BRT proj- into City Streets, 1996 (15 ) ects and a comparison of BRT to LRT to gain insight and provide definition to BRT. As discussed in this article, key This report addresses the operating characteristics and safety characteristics of BRT systems are running ways, stations, experience associated with light rail transit operating in vehicles, service, fare collection, and ITS; however, these are shared (on-street or mall) ROWs, under slower speed con- not exhaustive and not exclusive features to BRT. Many cities, ditions (under 35 mph). Nine LRT systems were surveyed such as Miami, Pittsburgh, and Ottawa, Ontario, use abandoned (Baltimore, Boston, Buffalo, Calgary, Los Angeles, Port- freight rail lines to provide exclusive busways. Although effi- land, Sacramento, San Diego, and San Francisco) to obtain ciencies are found when buses run in exclusive ROWs, it is information on their operating practices, safety concerns, not always financially feasible and BRT can function within accident experiences, innovative features, and enforcement mixed-traffic operation and experience similar efficiencies and safety education programs. through the proper execution of, for example, AVL and traf- fic signal technology. Furthermore, with proper marketing For LRT operations that physically operate on-street, both and branding, the use of several of these elements can set semi-exclusive and nonexclusive alignments are defined. BRT apart from other transit systems. This was found to be Semi-exclusive alignments are characterized with limited true through the review of implemented BRT projects, specif- grade crossings, and some physical separation of the LRT ically the Los Angeles County Metropolitan Transportation alignment from motor vehicle traffic is provided, ranging from Authority (MTA) Metro Rapid BRT system. Efforts to distin- raised curbs and fencing to mountable curbs, raised pavement guish BRT lines do not always accompany ROWs; however, markers, and/or striping. This concept is similar to the median the use of other distinguishing features such as simple routes transitway defined in chapter two. Operating speeds are typi- throughout the area, frequent service, separated and differenti- cally governed by vehicle speed limits where automatic cross- ating stations, and color-coded buses help create pseudo- ing gates are not provided. Nonexclusive alignments allow for rail operations in mixed traffic. mixed traffic flow with motor vehicles or pedestrians, result- ing in a higher level of operating conflict and slower oper- ating speeds. Nonexclusive alignments are typically applied in "Transit Corridor Evaluation and Prioritization downtown areas and for most streetcar applications. Framework," TRB 2006 (14 ) The research identified several problems associated with This report presents the evaluation methodology that was on-street operation of light rail, and identified potential developed and used by Hillsborough Area Regional Tran- solutions. The problems and solutions addressed include: sit (HART) (Tampa, Florida) to evaluate and prioritize key transit corridors, or Transit Emphasis Corridors (TECs). This Pedestrian safety (trespass on tracks, jaywalk, station, methodology is a planning-level tool to verify if specific and/or cross-street access) improvements relating to bus service, preferential treatment, Side-running alignment and/or facilities are warranted. Although it requires tailoring, Vehicles operating parallel to LRT ROW, turning left the methodology developed is intended to be applied by any across tracks (illegal left turns, protected left-turn lanes community establishing priority corridors. with signal phases) Traffic control observance (passive and active turn The methodology focuses on three categories of improve- restriction sign violations, confusing traffic signal dis- ments: service improvements, bus preferential treatments, plays, poor delineation of dynamic envelope)