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28 New transfer stops Operational Issues with the Installation of the New Transfer Stop (Figure 18, page 10) New transfer stops Lane Control Signals A B C D Queue Jump Operation with Lane Control Signals (Figure 19, page 11) FIGURE 26 Queue jump with lane control signals (Heron/Bronson Type) (27). Data were collected including pedestrian volumes, bus ridor increased between 7% and 46%. Before installation dwell times, bus and vehicle speeds near a bus stop, bus of the bus bulb, buses would often stop partially or fully and vehicle speeds for the corridor, the length of queue behind within the travel lane and would also use both travel lanes a bus, and driver behavior near the bus stop. when maneuvering away from the bay stop. Once the bus bulbs were installed, buses reduced their use of both travel As part of this research, two before-and-after studies were lanes to leave the bus bulb stop, resulting in the increased conducted. The first was curbside analysis to determine if there bus and vehicle speeds. were improvements to pedestrian mobility and operations around a newly installed bus bulb. The second was a roadway In conclusion, this report found that bus bulbs are appropri- analysis to determine the advantages or disadvantages to traf- ate in areas with high-density developments and in which the fic and bus operations from the implementation of bus bulbs percentage of people moving through the corridor as pedestri- at far-side and near-side bus stops. In general, pedestrians ben- ans or in transit vehicles is relatively high in comparison with efited from the additional sidewalk capacity by providing addi- the percentage of people moving in automobiles. Furthermore, tional room for queuing, which reduced conflicts between wait- the average flow rate of pedestrians traveling along the side- ing and walking pedestrians. It was found that the additional walk adjacent to the bus stop improved when the bus bay was space provided by the bus bulb improved pedestrian flow replaced with a bus bulb. along the adjacent sidewalk by 11%. The roadway before- and-after study determined that the average vehicle and bus SUMMARY speed along the corridor and the block increased when the bus bulbs were installed. Specifically, in studying San Fran- Table 1 highlights the major features and conclusions of the cisco's replacement of several bus bays with bus bulbs, it documents related to transit preferential treatments reviewed was found that vehicle and bus speeds on the block and cor- in this literature search.

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29 TABLE 1 SUMMARY FEATURES AND CONCLUSIONS FROM DOCUMENTS IN LITERATURE REVIEW Document Focus/Objectives Major Findings/Conclusions Genera l NCHRP Report 143-- First comprehensive Minimu m of 60 buses per peak hour to Bus Use of Highways-- documentation of bus operations justify use of exclusive bus lane, and lane State of the Art (1973) and priority treatments in U.S. should carry at least 1.5 times the number and internationally. 165 of general traffic vehicle occupants. treatments evalu ated. Identified bus travel time savings with different treatments. NCHRP Report 155-- Extension of NCHRP Report 143. Suggested values for one-way peak hour Bus Use of Highways: Presents planning and design volumes for priority treatments: curb bus Planning and D esign guidelines for bus operations and lanes (within CBD)--2030, curb bus Guidelines (1975) priority treatments. lanes--outside CBD--4060, median bus lanes/transitway--6090, contraflow lanes--extended length--4060, short segment--2030, bus "preemption"--10 15, special bus signal--510 TCRP Report 100: First comprehensive manual Presents bus capacity calculation Transit Capacity and documenting transit capacity and procedures for mixed traffic and bus lane Quality of S ervice quality of service principles and applications (integrating results Manual--2nd ed. (2003) procedures. documented in TCRP Report 26). TCRP Report 118: BRT Information on different bus Presents examples of calcu lations to Practitioner's Gu ide priority treatments including identify the cost and impact of different (2007) exclusive lanes, signal priority, BRT component packages associated curb extensions, and limited stop with a route or corridor, including spacing on arterial streets. integration of bus priority treatments. TCRP Report 90: Bus Assessment of 26 BRT projects Identified travel time, on-time Rapid Transit--Volum e throughout the world. performance, and other benefits 1: Case S tudies in Bus associated with bus priority treatments. Rapid Transit (2003) Bus Rapid Transit Guidelines for providing BRT in Identified travel time savings ranging Options in D ensely densely developed areas withou t from 0.4 to 11.4 min per mile for 20 Developed Areas (1975) freeways, focusing on arterial bus North American and European bus lane lanes. Input to NCHRP Report applications. 155. B us Semi-Rapid Presentation of "semi-rapid " Identification of three right-of-way Transit Mode concept for BRT. categories (A, B, C) for BRT operation on Development and urban streets. Evalu ation" (2002) "Bus Semi-Rapid Presentation of "semi-rapid " Identification of three right-of-way Transit Mode concept for BRT. categories (A, B, C) for BRT operation on Development and urban streets. Evalu ation" (2002) "Toward a Systems A review of the operation of the Identified effectiveness of bus priority Level Approach to San Pablo Avenue BRT line in treatments and signal timing optimization. Sustainable Urban Oakland. Arterial Revitalization: a Case Study of San Pablo Avenue" (2006) "Characteristics of Bus Description of BRT Tradeoffs identified between investing in Rapid Transit Projects: characteristics, including priority bus priority treatments vs. other BRT an Overview" (2002) treatments, and comparison with features. LRT. Characteristics of Bus Description of BRT Tradeoffs identified between investing in Rapid Transit Projects: characteristics, including priority bus priority treatments vs. other BRT An Overview (2002) treatments, and comparison with features. LRT. TCRP Report 17: Assessment of operating Set of solu tions to address potential Integration of Ligh t Rail characteristics and accident conflicts between LRT and general traffic Transit in to City Streets experience for different LRT and pedestrians. Location criteria (1996) alignment options on urban identified for placement/design of LRT streets. alignments along urban streets. Exclusive Lanes TCRP Report 26: Guidelines for calculating the Look-up tables and adjustment factors to Operational Analysis of capacity and bus speeds for account for different bus and adjacent Bus Lanes on Arteria ls different bus lane configurations traffic volu mes, stop frequency, and dwell (1997) in urban areas. times, for single and dual bus lanes. (continued on next page)

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30 TABLE 1 (continued) Document Focus/Objectives Major Findings/Conclusions TCRP Research Results Applied methodologies from Data collected on bus speeds, site Digest 38: Opera tional TCRP Report 26 to evalu ate the conditions, and traffic signal timing. Analysis of Bus Lan es performance of six existing Adjustments in procedures from TCRP on Arterials: arterial bus lanes in Portland Report 26 to reflect bus platooned Application and (OR); New York City; Ottawa, operations and incremental traffic delay. Refinem ent (2000) (ON); and San Antonio "A New Methodology Methodology for defining Use of bi-level programming to minimize for Optimizing Transit optimal number of exclusive total travel time in assessment. Priority at the Network transit lanes in transport network. Level" (2007) Transit Signal Priority/Specia l S ignal Phasing "An Overview of First comprehensive document Provided strategies for deployment of Transit Signal Priority" describing the transit signal TSP, including desired intergovernmental (2002) priority concept and applications, arrangements, and addressing TSP design benefits, and costs. and operations/maintenance issues. Case studies of TSP impact in eight North American cities. Improving VISSIM simulation analysis to A 10-s green extension was evalu ated for Transportation Mobility, evalu ate alternate transit signal headways of 15 and 30 min. Bus travel Safety, and Efficien cy: priority strategies along two bus times were found to be reduced by up to Guidelines for Planning routes in Montpelier, VT. 5.8%, bus delays reduced by up to 16.5%, and Deploying Tra ffic and on-time performance improved by up Signal Priority to 27.9%. Strategies (2008) Compreh ensive Study to assess the impacts of a TSP effectiveness measures applied Evalua tion of Transit regional TSP strategy in Sou th included transit time match, transit travel Signal Priority System Snohomish County, WA. Two time, traffic queu e length, signal cycle Impacts Using Field corridors evalu ated. failures, and frequency of TSP calls. Observed Tra ffic Data Evalu ation found improved on-time (2008) performance and less total person trip delay with TSP implementation. "Active Transit Signal Reviews the application of TSP Toronto streetcar system has seen dalay Priority for Streetcars-- to streetcar systems in Toronto reduction of 12 to 16 s per intersection Experience in Toronto and Melbourne, Australia. and travel tiume savings of 7 to 11 min and Melbourne" (2007) per route. "Evaluation of Transit Presents results of simulation Evalu ation of green extensions and recalls Signal Priority Benefits analysis of implementing five on a 5-s-increment basis within a fixed- along a Fixed-Time alternative TSP strategies along time traffic control environment. Signalized Arterial" Columbia Pike in Northern Greatest benefit associated with TSP was (2001) Virginia. found during mid-day period owing to lower traffic volumes and fewer TSP calls. "Critical Factors Presents framework for an ideal A real-time control strategy has the most Affecting Transit Signal transit signal priority system and potential to redu ce delays to non-transit Priority " (2003) its impact on traffic operations. traffic Queue Jump/Bypass Lanes The Tail of S even Queu e Describes seven different types Al identified queu e jump treatments Jumps (2008) of queue jump treatments at resulted in more efficient TSP operation intersections and transit travel time savings. "Design of Transit Comparison of the effectiveness VISSIM simulation was performed for Signal Priority at of TSP in mixed traffic vs. use of near and far side bus tops under both Intersections with queue ju mp lanes. mixed-lane TSP and jump-lane TSP. Queue Ju mper Lanes" Analysis showed the greatest bus delay (2007) reduction (3% to 17%) with jump-lane TSP and near-side stops. Curb Extensions TCRP Report 65: Evalu ated bus bulbs in several Two before-and-after studies conducted Evalua tion of Bu s Bu lbs North American cities to estimate in San Francisco involving curbside and (2001) the effect of such treatments on roadway analysis. With bus bu lbs, transit operations, vehicu lar pedestrian flow adjacent to stops traffic, and pedestrian improved by 11%. movements. CBD = central business district; HART = Hillsborough Area Regional Transit; VISSIM = VISual SIMulation model.