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Bus and Rail Transit Preferential Treatments in Mixed Traffic (2010)

Chapter: Chapter Two - Types of Transit Preferential Treatments

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Suggested Citation:"Chapter Two - Types of Transit Preferential Treatments." National Academies of Sciences, Engineering, and Medicine. 2010. Bus and Rail Transit Preferential Treatments in Mixed Traffic. Washington, DC: The National Academies Press. doi: 10.17226/13614.
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Suggested Citation:"Chapter Two - Types of Transit Preferential Treatments." National Academies of Sciences, Engineering, and Medicine. 2010. Bus and Rail Transit Preferential Treatments in Mixed Traffic. Washington, DC: The National Academies Press. doi: 10.17226/13614.
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Suggested Citation:"Chapter Two - Types of Transit Preferential Treatments." National Academies of Sciences, Engineering, and Medicine. 2010. Bus and Rail Transit Preferential Treatments in Mixed Traffic. Washington, DC: The National Academies Press. doi: 10.17226/13614.
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Suggested Citation:"Chapter Two - Types of Transit Preferential Treatments." National Academies of Sciences, Engineering, and Medicine. 2010. Bus and Rail Transit Preferential Treatments in Mixed Traffic. Washington, DC: The National Academies Press. doi: 10.17226/13614.
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Suggested Citation:"Chapter Two - Types of Transit Preferential Treatments." National Academies of Sciences, Engineering, and Medicine. 2010. Bus and Rail Transit Preferential Treatments in Mixed Traffic. Washington, DC: The National Academies Press. doi: 10.17226/13614.
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Suggested Citation:"Chapter Two - Types of Transit Preferential Treatments." National Academies of Sciences, Engineering, and Medicine. 2010. Bus and Rail Transit Preferential Treatments in Mixed Traffic. Washington, DC: The National Academies Press. doi: 10.17226/13614.
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Suggested Citation:"Chapter Two - Types of Transit Preferential Treatments." National Academies of Sciences, Engineering, and Medicine. 2010. Bus and Rail Transit Preferential Treatments in Mixed Traffic. Washington, DC: The National Academies Press. doi: 10.17226/13614.
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Suggested Citation:"Chapter Two - Types of Transit Preferential Treatments." National Academies of Sciences, Engineering, and Medicine. 2010. Bus and Rail Transit Preferential Treatments in Mixed Traffic. Washington, DC: The National Academies Press. doi: 10.17226/13614.
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Suggested Citation:"Chapter Two - Types of Transit Preferential Treatments." National Academies of Sciences, Engineering, and Medicine. 2010. Bus and Rail Transit Preferential Treatments in Mixed Traffic. Washington, DC: The National Academies Press. doi: 10.17226/13614.
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Suggested Citation:"Chapter Two - Types of Transit Preferential Treatments." National Academies of Sciences, Engineering, and Medicine. 2010. Bus and Rail Transit Preferential Treatments in Mixed Traffic. Washington, DC: The National Academies Press. doi: 10.17226/13614.
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Suggested Citation:"Chapter Two - Types of Transit Preferential Treatments." National Academies of Sciences, Engineering, and Medicine. 2010. Bus and Rail Transit Preferential Treatments in Mixed Traffic. Washington, DC: The National Academies Press. doi: 10.17226/13614.
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Suggested Citation:"Chapter Two - Types of Transit Preferential Treatments." National Academies of Sciences, Engineering, and Medicine. 2010. Bus and Rail Transit Preferential Treatments in Mixed Traffic. Washington, DC: The National Academies Press. doi: 10.17226/13614.
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5OVERVIEW There are several different types of transit preferential treat- ments that can be applied on urban streets. These can be divided into treatments applied over a given roadway segment or at a specific location (typically at an intersection). Two basic types of treatments have been identified, three related to roadway segments and four to spot locations. Roadway Segments • Median transitways, • Exclusive transit lanes outside a median area (concurrent- flow, contraflow, bi-directional, intermittent lanes), and • Stop modifications (limited stop spacing/stop consolidation). Spot Locations (Intersections) • TSP, • Special signal phasing, • Queue jump and bypass lanes, and • Curb extensions. The extent of the preferential treatment (e.g., longer length of exclusive transit lane or more green time for signal priority), along with traffic conditions along the roadway, will deter- mine the impact on both transit and traffic operations. Treat- ments can be applied at isolated locations where there is a particularly high delay to transit vehicles or as a series of treat- ments strung together in a corridor of some length to have a greater impact on travel time savings and improved reliability. This chapter presents the basic characteristics of the differ- ent transit preferential treatments addressed in this report. MEDIAN TRANSITWAYS Median transitways are exclusive transit facilities developed in the median of an urban street. Most applications in North America to date have been associated with light rail transit (LRT) lines, although there are a few median busways emerg- ing. These facilities typically have one lane in each direction, with a dedicated right-of-way (ROW) for the running way and stations. With the development of median transitways, minor unsignalized street intersections and local access drive- ways with the transit corridor are typically converted to right- in, right-out operation. Transitways interface with general traffic at signalized intersections, where cross streets remain and both left turns on the street the transitway is operating on and cross street traffic typically is accommodated at-grade. To accommodate left turns and U-turns for general traffic on the transitway street, dedicated left-turn lanes are provided to allow protected left-turn phasing to be provided, given the median separation and presence of the transitway. Median transitways typically have stations at signalized intersections, where pedestrians can access the station plat- forms using crosswalks and pedestrian signal phasing. Generally, far-side stations are provided to facilitate the pro- vision of signal priority for transit vehicles. Typically, side platforms have been applied for median busways and street- car lines because of right side running and doors on the right side of the vehicle. However, there have been some recent applications (in Cleveland and Eugene–Springfield, Oregon) of single center platforms and left side doors (doors on both sides of a bus). Because of the typical limited width of median areas and the overall roadway ROW, most median busways do not incorporate passing lanes, with added width only provided for stations. Examples of a median transitway for LRT operations in Phoenix are shown in Figure 1, and the former bus median transitway in Richmond, British Columbia, in Figure 2 (Richmond’s busway was recently replaced by an aerial rail rapid transit line). To keep general traffic and pedestrians out of a median transitway, some physical separation between the transitway and the adjacent general traffic lanes is provided, ranging from the use of jersey barriers and raised pavement markers, where limited ROW exists, to wider landscaped median treat- ments where more space is available. Added signing at inter- sections designating “Do Not Enter” and “Pedestrians/ Bicycles Prohibited” are typically provided. EXCLUSIVE TRANSIT LANES Exclusive lanes used by transit on urban streets include new lanes developed along a roadway through widening or dedica- tion of one or more existing general traffic or parking lanes for CHAPTER TWO TYPES OF TRANSIT PREFERENTIAL TREATMENTS

6on-street parking and having transit vehicles operate in the parking lane, (2) using a general traffic lane if there is no park- ing, or (3) using the general traffic lane outside (or left) of a parking lane. With this treatment, right-turn and local access driveway traffic are allowed to use the lane over short distances. In some cases, such as in Toronto and Vancouver, carpools and vanpools are allowed to use exclusive bus lanes as a through route as a high-occupancy vehicle (HOV) lane. In a few cases, such as on Madison Avenue in New York City, dual concurrent-flow bus lanes are included to provide added capacity and bus bypass capability. Concurrent-flow lanes can be developed in different oper- ating configurations: • A lane in each direction of travel operating at the same time over a designated time period; • A single lane operating in the peak traffic direction dur- ing one peak period, with a lane developed in the oppo- site direction during the opposite peak traffic period; and • A single lane operating in one direction during one time period, then reversed to operate in the opposite direc- tion during another time period (also referred to as a reversible lane). The most common form of a concurrent-flow transit lane is one located at the right side of the street, adjacent to the curb or the shoulder. Although this layout is common throughout North America, simply installing a curbside tran- sit lane does not imply the creation of an exclusive transitway, because curb transit lanes are subject to a variety of interfer- ence and conflicts, including right-turning vehicles, vehicles seeking to park or load at the curb, and vehicles entering or exiting at local driveways. In this context, maintaining the integrity of the transit lane through signs, markings, educa- tion, and ongoing enforcement is critical to ensuring the speed and reliability of bus service in these lanes. A variation of the curb transit lane that addresses some of these conflicts is an “interior” or “offset” bus lane, which operates in the lane adjacent to the curb lane. This configura- tion leaves the curb lane available for other uses, including direct curb access for loading and parking and right-turn lanes. The negative aspect of an interior or “offset” transit lane is that it has a significant impact on the travel capacity of the street, whereas the installation of a curb bus lane on a street by replacing on-street parking will not change capac- ity. However, in some locations there may be less concern about eliminating roadway capacity, particularly if there are good alternative routes, as compared with eliminating park- ing or loading that may have a greater impact on the viability of local businesses. Figure 3 illustrates concurrent-flow bus lanes in operation in Boston, London, and New York. Figure 4 shows similar lanes for streetcars in Portland (Oregon) and Toronto. FIGURE 1 Median LRT transitway in Phoenix, Arizona (Source: Valley Metro Rail). FIGURE 2 Former median bus transitway in Richmond, British Columbia (Source: Alan Danaher). transit use. These lanes can be designated for transit use dur- ing peak periods only, or all day. These lanes typically allow use by general traffic, for left- or right-turn movements, and local access driveway in and out movements. Most exclusive lane treatments are used by buses and streetcars, given that these vehicles better mix with general traffic and the vehicle lengths are relatively short, thus not blocking local access driveways. There are four kinds of exclusive lanes: • Concurrent-flow, • Contraflow, • Bi-directional, and • Intermittent. Concurrent-Flow Lane A concurrent-flow lane is a designated lane for transit vehicles moving in the same direction as general traffic. This lane is typ- ically developed on the right side, adjacent to the curb or shoul- der. The lane is typically developed either by (1) removing

FIGURE 3 Exclusive concurrent-flow bus lane applications: (a) Washington Street, Boston, Massachusetts (offset bus lane) [Source: APTA BRT Guideways Guidelines (6)]; (b) London, United Kingdom (curb bus lane) [Source: APTA BRT Guideways Guidelines (6)]; (c) Madison Avenue, New York City (dual bus lanes) [Source: TCRP Report 118 (5)]. FIGURE 4 Alternate streetcar running way configurations: (a) Portland, Oregon—one-way shared with traffic; (b) Toronto—two-way shared with traffic (Source: www.lightrail.com). (a) (b) (c) (a) (b)

Contraflow Lane Contraflow transit lanes involve designating a lane for exclu- sive transit use in the direction opposite that of general traffic. Contraflow lanes are applied almost exclusively on one-way streets, with bus lanes typically being no more than one to two blocks in length, with longer segments for LRT. With longer segments, lane use control signals need to be applied to properly alert general traffic and transit operators of the direction of use of the lane. Figure 5 illustrates a bus contraflow lane in downtown St. Petersburg, Florida, and Figure 6 illustrates a contraflow LRT lane in downtown Denver. Bi-Directional Lane A bi-directional transit lane is an exclusive lane that allows a transit vehicle (typically a bus or streetcar) to pass in one direction through a constrained section while a transit vehicle waits or dwells at a station or bypass area until it can be given 8 the green signal to pass though the section in the other direc- tion. This strategy is used when there is only enough room to install a single transit lane of restricted length to traverse through no more than two to three signalized intersections, and with longer service headways. It is noted that the signal system needs to have safeguards that “block out” the sec- tion so that only one transit vehicle can be in the section at a time. It is worth noting that when comparing the operations of a bi-directional lane with a transit vehicle traversing the section in question in mixed-use lanes, the bi-directional lane exclusivity can provide some level of reliability over a con- gested mixed-traffic scenario. Figure 7 provides an example of a bi-directional lane applied on the Eugene–Springfield, Oregon, BRT line. Intermittent Lane An intermittent bus lane or IBL, which can also be called a moving bus lane, is a restricted lane for short time duration only. This concept consists of using the general-purpose lane that can be changed to a bus-only lane only for the time needed for the bus to pass, after which the lane reverts back to a general-purpose lane until another approaching bus needs the lane for its movement. FIGURE 5 Contraflow bus lane on 4th Street, St. Petersburg, Florida (Source: Kittelson & Associates, Inc.). FIGURE 6 Downtown Denver LRT operation in curb lane (southbound on Stout Street) (Source: Denver Regional Transportation District). FIGURE 7 Bi-directional bus lane—Eugene–Springfield, Oregon, BRT (Source: Lane Transit District)

9From an operational protocol standpoint, the IBL system is to be activated only when the flow of the general traffic is operating below a speed that inhibits bus transit speeds. When that threshold is reached—through the technologies of computers and sensors that can provide knowledge of real-time traffic conditions—longitudinal flashing lights embedded in the roadway lane divider are activated to warn general-purpose drivers that they cannot enter that lane and a bus is approaching. Vehicles already in the lane are allowed to continue. This leaves a moving gap or moving time win- dow for the bus to travel through. For this treatment to be effective, driver education and enforcement is paramount. When the traffic conditions are not expected to cause delays to the bus movement, the IBL should not be activated. Figure 8 shows the signalization/signage for an inter- mittent lane demonstration project in Lisbon, Portugal. There currently is no application of intermittent lanes in North America. STOP MODIFICATIONS Modifications to stop placement can create some travel time savings for transit operations along urban areas or allow another preferential treatment (such as signal priority) to be more effectively applied. Given the relative inexpense of moving bus stops versus full LRT stations, modifications to stop placement are typically focused on bus operations, par- ticularly new BRT or express bus services. There are two types of stop modifications associated with the implementation of TSP: (1) stop relocation and/or con- solidation along a corridor, and (2) moving specific stops to enhance another priority treatment. Corridor Stop Relocation and/or Consolidation This strategy is applied when a new BRT or express bus ser- vice is implemented along a corridor. By having such services make fewer stops, travel time savings and improved on-time performance for the service as a whole can be achieved irre- spective of any added preferential treatments being applied. Where an average stop spacing might be two to three blocks for local bus service (800–1,200 ft), for new BRT service min- imum stop spacing is typically 0.5 to 1 mile. The 0.5 mile stop spacing is typically associated with 0.25 to 0.5 mile being an acceptable walking distance to such a premium bus service. For express bus service, stop spacing is even greater, with typically just a couple of intermediate stops between the outer stop of a line (in many cases associated with a park-n- ride facility) and downtown. It should be noted, however, that there are many cases where the existing local bus service alone has too many stops, and there are benefits of eliminat- ing or moving stops to go from a one- to two-block stop pat- tern to a three- to four-block stop pattern and provide some travel time savings and adequate accessibility to adjoining neighborhoods. In downtown areas, the concept of skip-stop operation is sometimes applied for bus operations. This concept FIGURE 8 Intermittent lane application—Lisbon, Portugal: (a) Vertical signalization—Variable message sign, (b) Horizontal signalization—Pavement light-emitting diodes [Source: “The Intermittent Bus Lane System: Demonstration in Lisbon” (7)]. (a) (b)

10 FIGURE 9 Bus stop spacing alternatives (Source: PB Americas, Inc.). FIGURE 10 Example of bus skip-stop pattern—17th Street, Denver, Colorado, Moving Specific Stops (Source: Denver Regional Transportation District). involves having bus routes stop at every second or third stop, thereby reducing the dwell time for buses at a stop and facilitating passenger boarding. This is not unlike the concept of having dedicated bus bays at a bus terminal. Critical to the success of skip-stop operations is the avail- ability of a passing lane that allows buses to pass one another. Figure 9 illustrates the relationship between local, limited and BRT, and express bus stop spacing patterns in a transit cor- ridor. Figure 10 shows the existing skip-stop bus operation on 17th Street in downtown Denver. This strategy is applied at a specific location, typically an intersection, where moving a stop (from near side to far side,

11 or far side to near side) can allow another preferential treat- ment to be applied or improve the performance of another preferential treatment. For TSP, having the transit stop far side at a signalized intersection will optimize the effectiveness of TSP, because transit vehicles can move through an intersection without stopping to pick up or discharge passengers near side. Far-side stops are also preferred where buses use a bypass lane near side to go through an intersection into a far-side stop, with or without supplemental signal priority. To implement a queue jump signal, having a near-side transit stop allows passengers to board and deboard before the signal is triggered. TRANSIT SIGNAL PRIORITY TSP alters traffic signal timing at intersections to give prior- ity to transit operating in a median transitway, in exclusive bus lanes, or in mixed traffic. TSP modifies the normal sig- nal operation to better accommodate transit vehicles while maintaining the coordinated operation and overall signal cycle length. TSP is different from signal preemption (typi- cally applied for emergency vehicles), where the normal sig- nal operation is interrupted through changing of the signal cycle length, thus taking the general traffic progression out of coordination associated with the preemption call. Signal pre- emption is used by LRT trains when they operate in a sepa- rate ROW and cross an urban street; however, the priority concept is applied when LRT trains travel along a street and cross an intersecting street. The usual TSP treatment is a minor adjustment in signal phase split times. The green phase serving an approaching transit vehicle may stay longer or start sooner, so that delay for a transit vehicle approaching an intersection can be reduced or eliminated. This is referred to as the “green extension/red truncation” concept. The expanded transit phase split time is recovered during the following signal cycle so that a corridor signal timing coordination plan can be maintained. This con- cept is illustrated in Figure 11. TSP can be activated either manually by the transit oper- ator or automatically using on-board technology. The auto- mated procedure is preferred because it eliminates the requirement for an operator to activate the emitter on the vehicle. In many cases, the automated TSP will be tied to an automatic vehicle location (AVL) or automatic passenger counter (APC) system that can determine if priority should only be given if a certain condition in the transit operation is being met—such as if the vehicle/train is behind sched- ule or if there are a certain number of passengers on board the vehicle/train. TSP detection can be identified by different means. In past years, many U.S. and Canadian agencies used optical detec- tion for transit priority requests from buses to signal con- trollers (see Figure 12). Inductive loop systems have also been applied, involving the use of an inductive loop embed- ded in the pavement and a transponder mounted on the underside of the transit vehicle. Another system includes use FIGURE 11 Red truncation/green extension TSP concept [Source: TCRP Report 118 (5)]. Bus approaches red signal RED TRUNCATION GREEN EXTENSION Bus approaches green signal Signal controller detects bus; terminates side street green phase early Signal controller detects bus; extends current green phase Bus proceeds on green signal Bus proceeds on extended green signal SIGNAL CONTROLLER

12 FIGURE 12 TSP bus detection concept—Optical system (Source: Kittelson & Associates, Inc.). FIGURE 13 TSP bus detection concept—Wayside reader system (Source: King County Metro). Connection to Checkout Unit Traffic Signal Controller Transponder Antenna Reader of radio frequency tags mounted on the vehicles that interact with wayside reader stations (see Figure 13). New detection systems involving the use of global positioning systems (GPS) and wireless technology are emerging. There are three types of TSP strategies: passive, active, and real-time priority. Passive strategies provide some level of transit priority through the use of pre-timed modifications to the signal system that occur whether or not a bus is present. Applications could range from just one signal to an entire signal system in a corridor. Active strategies adjust the sig- nal timing after a transit vehicle is detected approaching an intersection. Either unconditional or conditional priority can be applied as an active strategy. Unconditional priority pro- vides priority for all transit vehicles equipped with detection, whereas conditional priority only provides priority if a transit vehicle meets some condition based on AVL and/or APC data—such as if the transit vehicle is behind schedule or there are a certain number of passengers on-board. Real-time or adaptive strategies account for both transit vehicle and general traffic arrivals at an intersection or system of intersections and require specialized equipment capable of optimizing signal timings in the field to respond to current traffic conditions and transit vehicle location. TSP can be activated at either a distributed or centralized level. At the distributed level, decisions on TSP activation at an intersection are dependent on both the transit vehicle and signal controller. At the centralized level, the decision to acti- vate TSP is made by a centralized traffic management system. TSP is typically applied when there is significant traffic congestion and hence bus delays along a roadway. Studies have found that TSP is most effective at signalized intersec- tions operating under level of service “F” conditions, with a volume-to-capacity of ratio between 0.80 and 1.00. A basic guideline is to apply TSP when there is an estimated reduction in bus delay with negligible change in general traffic delay. Given this condition, the total person delay (on both buses and general traffic) would decrease with the application of TSP at a particular intersection or along an extended corridor. TSP also has a positive impact in reduc- ing travel time variability and hence keeping transit vehi- cles on schedule.

13 For mainline TSP to be most effective, it is important that transit stops be located on the far side of signalized inter- sections so that a bus activates the priority call and travels through the intersection and then makes a stop. For queue jump signal treatments where there is a designated transit stop at an intersection, the stop could be located either near side or far side. With a transit stop near side of the intersec- tion, the operator can trigger the priority call while passen- gers board and deboard. SPECIAL SIGNAL PHASING Another signal preferential treatment strategy is to introduce a transit-only signal or added signal phase into an intersection. This typically would involve provision for a special left-turn signal at a particular location to allow transit vehicles to make turns onto a cross street. Figure 14 shows a special bus left-turn signal implemented in Portland, Oregon. QUEUE JUMP LANE A queue jump lane is a relatively short lane that is available for transit vehicles to bypass general traffic at an intersection. It is typically associated with bus operations. The transit vehi- cle would enter into a right- or left-turn lane (the right lane being most common), or a new exclusive transit lane devel- oped on the intersection approach. The lane must be suffi- ciently long enough to allow transit vehicles to effectively access the lane without blockage if there is an adjoining through traffic queue. There are two types of queue jump lanes, depending on whether or not signal priority is provided with the bypass maneuver (see Figure 15). With Signal Priority With this queue jump treatment, a separate, short signal phase is provided to allow the transit vehicle an early green indication to move into the through lane or bus loading area far side of the intersection, ahead of through traffic. Typically, green time from parallel general traffic move- ment is reduced to accommodate the special bus signal phase, typically only 3 to 4 s. If there is an optional transit stop at an intersection, it typically would be located near side. With a near-side stop, passenger deboarding and boarding could occur during a red signal indication. In this situation, a signal priority call would be sent to the con- troller to activate the special signal phase immediately after the closure of vehicle doors. Figure 16 shows a queue jump signal in Portland, Oregon. Without Signal Priority If signal priority is not provided, a transit vehicle could still use a right-turn lane or right-side separate lane to bypass a general traffic queue, but then proceed under the normal through sig- nal phase into a far-side bus zone or bus pullout. In this case, the bus stop would typically be far side of the intersection. Figure 17 shows typical “Except Buses” signage associated with a bus bypass lane application. CURB EXTENSIONS Curb extensions (also known as bus bulbs) can serve as tran- sit preferential treatments on urban streets. This concept, typically applied with bus and streetcar operations, involves extending the sidewalk area into the street so that transit vehi- cles do not have to pull out of the travel lane to serve passen- gers at a stop. This eliminates the “clearance” time associated with transit vehicles at the curb at a stop waiting for a gap in the general traffic stream to pull back into the through lane. There can be significant travel time savings to transit when applied over a series of transit stops along a route. Curb extensions can be applied far side or near side of inter- sections (see Figure 18 for near-side treatments), or at mid- block (see Figure 19). To develop a curb extension, either a parking lane or loading zone must be available to develop the expanded passenger waiting area. This treatment typically requires the removal of two or more parking spaces or a load- ing zone to provide sufficient length to develop the curb exten- sion. Curb extensions can also provide space for landscaping and passenger amenities such as benches and pedestrian scale FIGURE 14 Special left-turn signal for buses—Portland, Oregon (Source: Kittelson & Associates, Inc.).

14 FIGURE 15 Bus queue jump signal/bypass lane concept [Source: TCRP Report 118 (5)]. FIGURE 16 Queue jump signal—Portland, Oregon [Source: TCRP Report 118 (5)]. FIGURE 17 “Except bus” signage used in bypass lane operations [Source: TCRP Report 118 (5)].

15 FIGURE 18 Near side curb extension placement [Source: TCRP Report 65 (8)]. FIGURE 19 Mid-block curb extension concept [Source: TCRP Report 118 (5)]. Before Bus pulls to curb at bus stop: must wait for gap in traffic to proceed. BUS STOP P Curb extended into parking lane, bus stops in travel lane; more curbside parking available. After BUS STOP P

lighting, assuming such features do not restrict intersection sight distance for traffic. Curb extensions also reduce the pedestrian crossing distance across the street on which the transit vehicle is operating. Curb extensions are normally applied when traffic volumes on an urban street are relatively low (up to 500 vehicles per lane), there are low-to-moderate right-turn volumes, and there are at least two lanes in the particular direction, which would allow general traffic to circumvent a stopped transit vehicle. This is particularly important with any far-side extensions, such that general traffic would not back up into the prior intersection. Curb extensions typically would not be located where there are high right-turn volumes, particularly truck movements, given the relatively tight curb radius associated with such treatments. Figure 20 shows a curb extension treatment developed in Portland, Oregon. 16 FIGURE 20 Curb extension treatment—Portland, Oregon [Source: TCRP Report 118 (5)].

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TRB’s Transit Cooperative Research Program (TCRP) Synthesis 83: Bus and Rail Transit Preferential Treatments in Mixed Traffic explores the application of different transit preferential treatments in mixed traffic. The report also examines the decision-making process that may be applied in deciding which preferential treatment might be the most applicable in a particular location.

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