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Bus Rapid Transit, Volume 2: Implementation Guidelines (2003)

Chapter: Chapter 3 - Running Ways

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Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
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Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
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Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
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Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
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Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
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Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
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Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
×
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Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
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Page 38
Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
×
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Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
×
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Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
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Page 41
Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
×
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Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
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Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
×
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Page 44
Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
×
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Page 45
Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
×
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Page 46
Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
×
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Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
×
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Page 48
Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
×
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Page 49
Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
×
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Page 50
Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
×
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Page 51
Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
×
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Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
×
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Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
×
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Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
×
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Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
×
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Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
×
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Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
×
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Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
×
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Page 59
Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
×
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Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
×
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Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
×
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Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
×
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Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
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Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
×
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Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
×
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Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
×
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Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
×
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Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
×
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Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
×
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Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
×
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Suggested Citation:"Chapter 3 - Running Ways." National Academies of Sciences, Engineering, and Medicine. 2003. Bus Rapid Transit, Volume 2: Implementation Guidelines. Washington, DC: The National Academies Press. doi: 10.17226/21947.
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3-1 CHAPTER 3 RUNNING WAYS Running ways are a key element of BRT systems, around which planning and design of the other components revolve (see Figure 3-1). Running ways should allow rapid and reli- able movement of buses with minimum traffic interference and provide a clear sense of presence and permanence. The basic goal of a running way is to give BRT an operating envi- ronment where buses are free from delays caused by other vehicles and by certain regulations and to provide transit riders with better, more reliable service. This chapter gives general design considerations and specific planning and design guidelines for principal types of running ways. Addi- tional planning and design guidelines can be found in various AASHTO, NCHRP, TCRP, and U.S. DOT publications (Bus Rapid Transit Options, 1975; Fitzpatrick et al., 2001; Guide, 2001; Levinson et al., 1975; Parsons Brinckerhoff Quade & Douglas, 2002; Texas Transportation Institute et al., 1998). 3-1. GENERAL CONSIDERATIONS General considerations include the following: (1) estab- lishing a BRT running way classification system, (2) defin- ing planning guidelines, (3) identifying desired facility per- formance, and (4) establishing key design parameters. 3-1.1. Classification Systems The types of running ways for BRT service range from mixed traffic operation to fully grade-separated busways. They may be classified according to the degree of access con- trol (traffic separation) or by type of facility. A suggested classification scheme by extent of access control is shown in Table 3-1. This system is similar conceptually to those used for highways and rail transit lines. The five classes range from full control of access such as grade-separated busways (Type I) to operation in mixed traffic (Type V). Table 3-2, in turn, groups running ways by busways, freeways, and arte- rial streets; identifies the specific facilities associated with each; and gives illustrative examples. 3-1.2. General Guidelines The following guidelines should underlie running way location and design: 1. Running ways should serve three basic service com- ponents—CBD distribution, line haul, and neighbor- hood collection—in a coherent manner. Generally, a variety of running way types will be used for each component and be customized to specific needs. Bus- ways or bus lanes will normally provide the line-haul service; CBD distribution may be provided in on- street bus lanes and off-street in bus tunnels, as well as on bus malls or through off-street terminals. Resi- dential distribution may be via bus lanes or in mixed traffic. A dedicated BRT corridor may consist of a number of segments, each with a different running way treatment. Examples of combinations of BRT running ways are shown in Figures 3-2, 3-3, and 3-4: • Figure 3-2 shows a basic BRT route that includes operations in mixed traffic flow, dual curb bus lanes, and a park-and-ride lot at the end of the line. • Figure 3-3 shows a comprehensive BRT system that includes running ways along freeways, arterial streets, and in separate rights-of-way. It also includes a short downtown bus tunnel that gives busways a traffic-free route through the city center. • Figure 3-4 shows how various BRT running ways can be coordinated and staged in the central area of a large city. The goal is to provide through routes that use bus lanes and bus streets, initially, and to incorporate a bus tunnel later, when demand and service levels warrant it. 2. Running ways should serve major travel markets, and they should penetrate these markets whenever possible. 3. Running ways generally should be radial, connecting the city center with outlying residential and commer- cial areas. Cross-town running ways may be appro- priate in large cities where they connect multiple trip attractors and residential concentrations and have fre- quent interchanging bus lines. Alignments should be direct, and the number of turns should be minimized. 4. BRT is best achieved by providing exclusive grade- separated rights-of-way to serve major markets. Such rights-of-way, however, may be difficult to obtain, costly to develop, and not always located in areas of the best ridership potential. Therefore, street running

3-2 ways or exclusive running ways with at-grade inter- sections may be essential. 5. Effective downtown passenger distribution facilities are essential in providing direct BRT service to down- town trip origins and destinations. Downtown distrib- ution should maintain service dependability, minimize time losses resulting from general traffic delays, and provide efficient pedestrian access and egress. 6. BRT running ways should follow streets that are rela- tively free flowing wherever possible. Speed and relia- bility should be enhanced by transit-sensitive traffic engineering, provision of bus-only lanes, and, in some cases, major street improvements. 7. Special running ways (busways, bus lanes, and queue bypasses) should be provided. This should happen when there is (1) extensive street congestion, (2) a sufficient number of buses, (3) suitable street geome- try, and (4) community willingness to support public transport, reallocate road space as needed, and enforce regulations. 8. Preferential treatments for buses may be provided around specific bottlenecks or along an entire route. Queue bypasses are very effective on approaches to water crossings, at major intersections, or at other traf- fic bottlenecks with extensive peak-hour congestion. Treatments that extend longer distances along BRT routes are desirable. 9. Running ways should maximize the person flow along a roadway with minimum net total person delay over time. There should be a net overall savings for all modes in terms of travel time per person. Where road space is allocated to BRT, the person minutes saved should be more than the person minutes lost by people in auto- mobiles. The number of persons traveling per hour in BRT should exceed the number of persons traveling per hour in any of the adjacent general purpose lanes within a 3- to 5-year period after the lane is placed in service. 10. An exclusive bus lane should carry significantly more people than an adjoining general traffic lane used dur- ing the peak travel periods. The number of bus riders in an exclusive bus lane should exceed the number of automobile occupants using adjacent lanes. 11. Buses should be able to enter and leave running ways safely and conveniently. Conflicts with other traffic should be avoided and, when necessary, carefully controlled. This is especially important in developing median and contra flow lanes and busways along arte- rial streets and within freeway corridors. There should be suitable provisions for passing stopped or disabled buses. 12. Running ways should provide a strong sense of iden- tity for BRT. This is especially important when buses operate in bus lanes or in arterial median busways. Using special colors in paving the lanes (e.g., green, yellow, or red) or using specialized materials that differentiate the bus lanes from general traffic lanes is desirable. 13. Adequate signing, markings, and traffic signal con- trols are essential. They are especially important at entry and exit points of arterial contra flow bus lanes and median busways, bus-only streets, bus- ways, and reserved freeway lanes. 14. Bus lanes and queue bypasses may be provided along both one-way and two-way streets. Concurrent flow bus lanes should generally allow at least two adjacent general traffic lanes in the same directions of travel. Contra flow lanes should allow at least two traffic lanes in the opposite direction of travel. Median arte- rial busways should allow at least one travel lane and one parking lane in each direction. In restrictive situ- ations, there should be at least one through and one left-turn lane each way on two-way streets. 15. Running way designs should be consistent with estab- lished national, state, and local standards. Although subject to unique local roadway conditions and demand, generally, the stops and stations should be accessible for all likely users and should permit safe bus, traffic, and pedestrian movement. 16. Running way designs may allow possible future con- version to rail transit without disrupting BRT opera- tions. Service during the construction period is desir- able for median arterial busways, busways on separate RUNNING WAY STATIONS VEHICLES BUS OPERATIONS TRAFFIC ENGINEERING SYSTEMS FARE COLLECTION Figure 3-1. The central role of running ways. TABLE 3-1 Running ways classified by extent of access control Class Access Control Facility Type I Uninterrupted Flow—Full Control of Access Bus Tunnel Grade-Separated Busway Reserved Freeway Lanes II Partial Control of Access At-Grade Busway III Physically Separated Lanes Within Street Rights-of-Way Arterial Median Busway, Bus Streets IV Exclusive / Semi-Exclusive Lanes Concurrent and Contra Flow Bus Lanes V Mixed Traffic Operations

3-3 TABLE 3-2 Examples of various types of running ways Facility Type Access Class Examples Busways Bus Tunnel Grade-Separated Runway At-Grade Busway 1 1 2 Boston, Seattle Ottawa, Pittsburgh Miami, Hartford Freeway Lanes Concurrent Flow Lanes Contra Flow Lanes Bus-Only or Priority Ramps 1 1 Ottawa New Jersey Approach to Lincoln Tunnel Los Angeles Arterial Streets Median Arterial Busway Curb Bus Lanes Dual Curb Lanes Interior Bus Lane Median Bus Lane Contra Flow Bus Lane Bus-Only Street Mixed Traffic Flow Queue Bypass 3 4 4 4 4 4 4 5 5 Curitiba, Vancouver Rouen, Vancouver Madison Avenue, NewYork City1 Boston Cleveland Los Angeles, Pittsburgh Portland1 Los Angeles Leeds, Vancouver 1Regular bus operations. 1 Curb bus lanes Parking Restricted Mixed Traffic with signal priorities No parking in peak hours Park-and-Ride Lot 5 Miles 5 Miles *schematic - not to scale CBD Figure 3-2. Illustrative BRT running ways using curb bus lanes and mixed flow. rights-of-way, and busways within freeway envelopes, with special attention paid to width-constrained areas and stations. 17. Running ways can be shared by BRT and LRT when they are designed to accommodate both transit types in terms of cross section, curves, grades, and vertical clearance. Stations should be able to serve both kinds of vehicles, speeds should be less than 35 miles per hour, and the two services should not conflict with one another. 3-1.3. Performance, Costs, and Capacities The performance and costs of BRT are related closely to whether the running way is located on city streets or on sep- arate (usually grade-separated) rights-of-way. As shown in Table 3-3, off-street busways generally provide twice the speed of on-street operations, but they cost more than twice as much. Operations on reserved freeway lanes can provide high speeds at modest costs, but they may make intermedi- ate stations difficult and lose the “identity” associated with other types of running ways. 3-1.3.1. Travel Time Savings Bus lanes and busways reduce travel times in general about 1.5 to 2 minutes per mile. Actual time savings are greatest when the previous speeds were the slowest (Figure 3-5). Bus delays are normally associated with passenger stops, traffic signal delays, and traffic congestion. Figure 3-6 illustrates the use of bus lanes to reduce bus delays. Further

Busway Busway Future Bus Tunnel Fr ee w ay Curb Bus Lanes CBD Core Curb Bus Lanes Curb Bus Lanes Limits of Central A rea Bus-Only Street Bus Bridge River *schematic - not to scale Figure 3-4. Illustrative coordination of BRT running ways in a downtown area. Mixed Traffic Flow Mixed Traffic Flow Interior Bus Lanes CBD Curb Bus Lanes Busway Bus Tunnel Metered Freeway Ramp Bus Ramps Median Arterial Busway Busway Along Freeway Bus fly-under at major cross road *schematic - not to scale Figure 3-3. Illustrative BRT running ways in a major metropolitan area.

3-5 TABLE 3-3 Running way costs and speeds Item Busway (Grade-Separated) Arterial Street Median Busway/Bus Lanes Typical Construction Costs (Millions per mile) $6–20 $1–10 Typical Speeds (Miles per hour) 25–40 12–20 SOURCE: Adapted from Levinson et al., 2003. ARTERIAL CBD (SOURCE: Texas Transportation Institute et al., 1998) Figure 3-5. Typical time savings—bus ramp transit options. time savings would result if passenger boarding and alight- ing times are reduced (e.g., through use of low floors, multi- ple wide doors, and off-board fare collection), and traffic sig- nal priorities are introduced. 3-1.3.2. Capacities The number of buses and passengers that can be carried along a BRT route depends on the type of running way, the design of stations and stops, the size, height, and arrangement of bus doors, the fare collection methods, the concentration of boardings at critical stops, and operating practices (see Appendix A for further details). The capacities associated with particular kinds of running ways are the following: • Where buses operate nonstop along freeways, have well- designed entry and exit points, and have adequately sized terminals, flows of 750 to 800 buses per lane per hour can be safely accommodated. • Busways with on-line stops and passing lanes at sta- tions can carry over 200 buses per hour each way, pro- vided that there is adequate capacity in downtown areas for buses. • The South American experience indicates that median arterial busways with on-line stops and passing lanes at stops can carry over 200 buses per hour. • Dual bus lanes on downtown streets carry 150 to 200 buses per hour total. Similar volumes can be carried in a single lane with more frequent stops if there is off- board fare collection, noncash fares, and multidoor boarding. • Curb bus lanes on city streets typically can accommodate a maximum of 90 to 120 buses per hour. 3-1.4. Bus Design Parameters Running way planning and design should reflect the char- acteristics and capabilities of buses currently in operation and those planned for BRT service. Figure 3-7 shows an example of a typical 60-foot articulated bus that would gov- ern BRT running way design. Additional examples of design vehicles can be found in NCHRP Report 414: HOV Systems Manual (Texas Transportation Institute et al., 1998) pub- lished by the Transportation Research Board (see Chapter 6 for a further discussion of BRT vehicles). Tables 3-4 and 3-5 provide select design and performance characteristics, respectively. Further details are contained in Appendix C. These exhibits suggest the following general guidelines: 1. Length and Height. The design single-unit bus is 40 feet long, and the design articulated bus is 60 feet long (the dual articulated buses in use in South America have a

3-6 (SOURCE: St. Jacques and Levinson,1997) Figure 3-6. Bus travel time rates by time component. (SOURCE: North American Bus Industries, Inc.) Figure 3-7. Bus vehicle designs.

design length of 80 feet). Buses are generally 11 feet high; a minimum vertical design envelope of 13 feet is suggested, which typically translates into 14 feet and 6 inches of vertical clearance to allow for pavement resurfacing. Where LRT operates, the vertical clear- ance should be a minimum of 16 feet under structures and 18 feet at street intersections. 2. Width. Buses are 8 feet and 6 inches wide. However, when mirrors are added for both sides, the bus envelope becomes 10 to 10.5 feet. Therefore, 11 feet is suggested as the minimum lane width. Wider bus lanes are desir- 3-7 able for areas with higher design speeds. If the mirror- to-mirror envelope on 102-inch buses can be the same as that for 96-inch buses, 10-foot lanes could be used when space is constrained and speeds are low. 3. Eye Height. An eye height of 5 feet should be used in roadway design, although the driver’s eye height on most buses is approximately 7 feet. This allows a fac- tor of safety for potential new equipment and for pos- sible use of bus lanes and busways by other public transportation vehicles (e.g., minibuses, paratransit vans, or maintenance vehicles). 4. Turning Radius. The minimum outside turning radius of the front overhang of an articulated bus has been reported to be about 45 feet. A slightly larger radius (e.g., 50 to 55 feet) should be used for design purposes. 5. Acceleration and Deceleration. Normal bus accelera- tion of 1.5 miles per hour per second and normal decel- eration of 2.0 miles per hour per second should be assumed. Maximum deceleration in emergencies should not exceed 5 to 6 miles per hour per second when there are standing passengers. These rates reflect the perfor- mance capabilities of most urban transit buses and permit buses to accelerate to 30 miles per hour in 20 seconds. TABLE 3-4 Bus design characteristics VEHICLE DIMENSIONS (All measurements in feet, unless otherwise noted) 40-FT REGULAR BUS 45-FT REGULAR BUS 60-FT ARTICULATED BUS Length 40 45 60 Width without Mirror 8.5 (b) 8.5 (b) 8.5 (b) Height (to top of air conditioning) for Design 9.8–11.1(c) 12.5(c) 11.0(c) Overhang Front 6.9–8.0 ft 7.9 8.8–8.9 Rear 7.5–9.5 ft 9.8 8.6–9.7 Wheel Base–Rear 23.3–24.9 22.9 23.3–24.5 Driver’s Eye Height 7 (a) 7 (a) 7 (a) Weight (lbs) Curb Weight 27,000–28,200 38,150 38,000 Gross Weight 36,900–40,000 55,200 66,600 Entrance Steps from Ground 1.5 1.5 1.5 Ground to Floor Height 2.3 2.3 2.3 Passenger Capacity Seats 45–50 50 76 Standees (crush load) 20 28 38 Turning Radius Inside 24.5–30 27.3 Outside 42.0–47 39.8–42.0 Outside with Overhang 45.5–51 44.3 Number of Doors 2 2 2 Width of Each Door 2.3–5.0 2.5–5.0 2.5–5.0 Angles (degrees) Approach 10 10 10 Breakover 10 10 10 Departure 9.5 9.5 9.5 NOTES: (a) Used 5 feet for design. (b) With mirrors envelope becomes 10 to 10.5 feet. (c) Used 13 feet as minimum governing design clearance. SOURCES: A Policy on Geometric Design, 2001; Design Criteria, 2002; Fuhs, C., 1990; Levinson, et al., 1975. TABLE 3-5 Bus performance characteristics Item Maximum Attainable Speed (mph) 50–70 Acceleration (mph/sec) 0–10 mph 3.33 10–30 mph 2.22 30–50 mph 0.95 Deceleration (mph/sec) Normal 2–3 Maximum 6–2 Maximum Grade (%) 10%

3-2. ON-STREET RUNNING WAYS On-street BRT running ways can provide downtown and residential distribution. They can serve corridors where mar- ket factors, costs, or right-of-way availability preclude pro- viding busways (or reserved freeway lanes). They also may serve as the first stage of future off-street BRT development and to establish ridership during the interim. Running ways vary in (1) whether they provide special facilities for buses; (2) how they place bus lanes (curb or median); (3) direc- tion of flow (concurrent or contra); (4) mix of traffic (buses only, buses and taxis, and buses and goods delivery vehicles); and (5) traffic controls (parking, turn controls, loading, and signalization). Running ways include (1) operation in mixed traffic, (2) con- current flow bus lanes, (3) concurrent “interior” bus lanes, (4) contra flow bus lanes, (5) median bus lanes, and (6) arte- rial median busways. Running ways are a logical component of traffic management strategies that specialize street use and give preference to public transport. The reasons for giving buses priority on streets and high- ways are (1) maximizing total person-carrying capacity of the street or highway, (2) minimizing net total all-mode per- son delay, (3) helping protect public investments in transit by maintaining service reliability and high speeds, and (4) favor- ing public transport for environmental preferences. 3-2.1. General Guidelines The following factors should be considered in achieving effective BRT use of city streets and suburban roads: 1. General traffic improvements and road geometric design should be coordinated with BRT service to improve the overall efficiency of street use. Typical improvements include prohibiting curb parking, adding turning lanes, prohibiting turns, modifying traffic sig- nal timing, and providing queue bypasses for buses. 2. Curb parking generally should be prohibited before (curb) bus lanes are established, at least during peak hours. The prohibition (1) makes it possible to pro- vide a bus lane without reducing street capacity for other traffic, (2) reduces delays and marginal frictions resulting from parking maneuvers, and (3) gives buses easier access to stops. (When prohibiting curb parking is not practical, the bus lane should be provided in the lane adjacent to the parking lane.) Bus lanes off- set from the curb can provide benefits without parking and access restrictions. The trade-off is potential con- flicts between parkers and buses. 3. Bus routes should be restructured as necessary to make effective use of bus lanes and bus streets. When BRT vehicles exceed 40 buses per hour, they should have exclusive use of the running way lane. When ser- vice is less frequent, it may be desirable to operate local buses on the same facility. However, this should 3-8 not create bus-bus congestion or create passenger inconvenience. Peak-hour one-way bus volumes rang- ing from 60 to about 75 buses will help “enforce” bus lanes without excessive bunching of buses. 4. Bus priority treatments should reduce both the mean and variability of average journey times. A 10 to 15% decrease in bus running time is a desirable objective for bus lanes. 5. Extended bus lanes are necessary to enable BRT sched- ule speeds to achieve significant time savings, better service, reliability, and increased ridership. A savings of 1 minute per mile (equivalent to raising bus speeds from 10 to 12 miles per hour) could produce a 5- to 6-minute time savings if achieved over the entire length of a typical 5-mile bus journey. Additional sav- ings could result from traffic signal priorities. Time savings can translate into higher ridership/revenue and lower costs. 6. Emergency vehicles, police cars, fire equipment, ambu- lances, and tour buses should be allowed to use bus lanes and bus streets. 7. Design and operation of bus lanes must accommodate the service requirements of adjacent land uses. Deliv- eries should be prohibited from bus lanes during the hours that the lanes operate. They can be provided from the opposite side of the street, from side streets, or, ideally, from off-street facilities. Accommodating deliveries is especially important when contra flow lanes are provided. 8. Access to major parking garages should be maintained. This may require limited local automobile circulation in the block adjacent to garages. 9. Taxi loading areas should be removed from bus lanes where they would interfere. On one-way streets the taxi loading areas should be placed on the opposite side of the street. 10. Pedestrian access to bus stops and stations should be convenient and safe. Curbside stops should allow suf- ficient space for waiting passengers, passing pedestri- ans, and amenities. Crosswalks to reach median bus lanes and busways should be placed at signalized locations with pedestrian cycles and be designed to discourage errant crossings. 11. Running way design should reflect available street widths and traffic requirements. Ideally, bus lanes should be provided without reducing the lanes available to through traffic in the heavy direction of flow. This may entail eliminating parking or reducing lane widths to provide additional travel lanes, eliminating left-turn lanes, and/or providing reversible lane operation. 12. When buses preempt moving traffic lanes, the number of lanes taken should be kept to a minimum. The excep- tion is when parallel streets can accommodate the dis- placed traffic. 13. Bus lanes and streets should provide a strong sense of identity. When buses have exclusive use of the lane, a

strong sense of identity can be achieved by using col- ored pavement, unique paving materials, signals, and pavement markings in various combinations. Such treatments are especially important for curb bus lanes whenever the lanes operate at all times. 14. Effective enforcement and maintenance of bus lanes and bus streets is essential. Fines for unauthorized vehicles should be high enough to discourage illegal use. 15. BRT bus lanes (and streets) should operate all day wherever possible. This will give passengers a clear sense of bus-lane identity and permit use of specially colored pavements. 16. Far-side bus stops generally should be provided. They are essential when there are traffic signal priorities for buses, as well as along median arterial busways where left-turn lanes are located near-side and where there are queue jumpers. Far-side bus stops are desirable when curb lanes are used by moving traffic and at locations with heavy right-turn traffic. 17. Reserving lanes and/or bus streets for buses must be perceived as reasonable by users, public agencies, and the general public. Concurrent flow bus lanes should be at least 11 feet wide for 8.5-foot-wide buses; 12- to 13-foot-wide bus lanes are desirable. Contra flow bus lanes should be at least several feet wider in areas of heavy pedestrian flow to provide a cushion between the bus lanes and opposing traffic and to let buses pass around errant pedestrians in the lanes. Bus streets and median arterial busways should be at least 22 feet wide. Median bus lanes need physical separation from general traffic for maximum effectiveness and enforceability. There- fore, physically separated median arterial busways are desir- able. Passenger loading and unloading islands at stops should meet Americans with Disability Act (ADA) requirements. Roadways should be at least 75 to 80 feet wide, and it is preferable that they are wider. 3-2.2. Mixed Traffic Operations BRT may operate in mixed traffic flow when physical, traffic-environmental conditions preclude busways or bus lanes, when streets and roads flow freely on “branch” BRT lines, and in residential collection. Advantages include low costs and fast implementation. However, such operations can limit bus speeds, service reliability, and route identity and should be used sparingly in trunk-line BRT service. Exam- ples include the Wilshire-Whittier and Ventura Boulevard Metro Rapid services in Los Angeles. Buses will usually benefit from street and traffic improve- ments that reduce overall delay. The range of transit-related traffic improvements includes the following: grade separa- tions to bypass delay points, street extensions to improve traf- fic distribution or to provide bus routing continuity, traffic signal improvements such as system coordination and bus pri- 3-9 orities or preemptions; intersection channelization improve- ments, turn controls that exempt buses, bus stop lengthening or relocation, longer curb radii and corner rounding, effec- tive enforcement and extension of curb parking regulations (especially during peak periods), and improved spacing and design of bus stops. It is generally better to operate buses in both directions on the same street from a standpoint of service clarity and iden- tity. However, one-way traffic flow generally improves travel speeds and safety and may be essential in central areas. 3-2.2.1. Bus Bulbs A bus bulb, a section of sidewalk that extends from the curb of a parking lane to the edge of an intersection or offset through lane, may have several advantages for BRT opera- tions. These advantages include (1) creating additional space for pedestrian amenities at stops, (2) reducing street crossing distances for pedestrians, (3) eliminating lateral changes of buses to enter and leave stops, (4) eliminating delays associ- ated with buses reentering a traffic stream, and (5) segregat- ing waiting bus passengers from circulating pedestrian flow along the sidewalk. However, bus bulbs may also produce traffic queues behind stopped buses that can cause drivers to make unsafe maneuvers when changing lanes to avoid a stopped bus. Bus bulbs may also preclude adding capacity for moving traffic, and they may cost more than conventional bus stops because of street drainage requirements. Supporting conditions for bus bulbs include (1) frequent bus service, (2) high passenger boardings and alightings, (3) sidewalks, (4) low traffic operating speeds, (5) two travel lanes each way to facilitate passing of stopped buses, and (6) difficult bus reentry into the traffic stream (Fitzpatrick et al., 2001). They also can be used when interior lanes rather than curb bus lanes are provided. Typical designs for bus bulbs are shown in Figures 3-8a and 3-8b. The “bus bulbs” should be 6 feet wide, leaving a 2-foot offset between the bulb and the edge of the travel lane. Bus bulbs should be long enough to accommodate all doors on buses. Bus stops that are 140 feet long can accommodate two articulated buses. The “transitions” to the existing curbs should be about 15 to 20 feet long and consist of two-reverse curves. 3-2.2.2. Queue Bypasses Queue bypasses (queue jumpers) may be used at signalized locations or other locations (e.g., at a narrow underpass or bridge) where traffic backs up during peak hours. The queue bypass could be shared with right turns; however, when right turns are heavy and/or operate when through traffic is stopped, separate right-turn and queue bypass lanes should be provided. Adequate distance should be provided on the far side of the intersection to enable easy reentry of buses. Bus stops should

be removed from the intersection. An “advance green” for buses could be provided when actuated by buses. The queue bypass should be distinctively identified by special pave- ment delineation. Queue bypasses should be used sparingly because they must be constantly enforced. Figure 3-9 shows typical queue bypass concepts; further details are contained in Chapter 4. 3-2.3. Concurrent Flow Curb Bus Lanes Concurrent flow bus lanes have been the most common type of bus priority treatment and can expedite BRT flow. Tradi- tionally, they have been used to facilitate bus movements in 3-10 CBDs by segregating buses from other traffic; however, they are also used along outlying arterials. 3-2.3.1. Design Features Concurrent flow bus lanes can operate at all times or just during peak hours. On one-way and two-way streets, an 11- to 13-foot bus lane should be provided along the curb (see Figure 3-10). However, when street width permits and there are high demands for curb access, a 20-foot-wide curb bus lane should be provided to enable buses to pass loading and unloading cars and trucks. (This arrangement is used in down- town San Francisco.) (SOURCE: Fitzpatrick et al., 2001) Figure 3-8a. Bus bulbs with near-side stops.

When street width and circulation patterns permit and peak bus volumes exceed 90 to 100 buses per hour, dual bus lanes should be considered. This arrangement is used along Madison Avenue in midtown Manhattan. It enables buses to pass each other safely, makes express stops and skip stops feasible and reduces the magnitude and variance of bus travel times. However, dual lanes preclude right turns by general traffic. When BRT and local buses use the same street and space permits, it may be desirable to provide turnouts for local bus stops. Curb lanes can be separated by solid white lane lines, by paving material with a different color or texture, or some- times by raised curbs. The lines should be broken where right turns are permitted. Photo 3-A shows an example of a run- ning way for the Boston Silver Line. Every effort should be made to eliminate turning move- ments that would impede bus service. Ideally, right turns should be prohibited when there are more than 300 pedestri- ans per hour in the conflicting crosswalk (see Chapter 4). Left turns by general traffic should be prohibited on four-lane streets unless special turn lanes are provided. 3-11 3-2.3.2. Assessment Concurrent flow curb bus lanes are the easiest to implement and have the lowest installation costs because they normally involve only pavement markings and street signs. They occupy less street space than most other types of bus lanes. Although these lanes are commonly used only during peak hours, they should operate throughout the day along BRT routes. Concurrent flow curb bus lanes are usually least effective in terms of image afforded and travel time saved. They are difficult to enforce and may impact curb access. Another dis- advantage is that right turns, when permitted, may conflict with bus flow. 3-2.4. Contra Flow Curb Bus Lanes Contra flow bus lanes enable buses to operate opposite to the normal traffic flow on one-way streets. They may be used for a single block on two-way streets to enable buses to reverse direction. They are used for distribution of busway and BRT vehicles in downtown Los Angeles and Pittsburgh. The lanes (SOURCE: Fitzpatrick et al., 2001) ADA Bulb Area Grass Strip On Street Parking Area Loading Area, no street furniture LEGEND Length of Bulb 40' - 50' per regular bus 60' - 70' per articulated bus Provide Bus Shelter with amenities at each. No Parking at least 30 ft. from intersection. ADA ADA6' 6' 15' Radius Reverse Curve Figure 3-8b. Bus bulb with far-side stops.

normally require one-way street systems with reasonable spacing between signalized intersections, generally 500 feet or more. They usually operate at all times. 3-2.4.1. Design Features Typical contra flow lane designs are shown in Figure 3-11. Contra flow bus lanes should be at least 12 feet wide. How- ever, a 13- to 15-foot-wide lane is desirable to let buses pass around pedestrians who step off the curb. Left turns in the opposing direction of travel should be prohibited unless protected storage lanes and special traffic signal phases are provided. Loading of goods should be prohibited from the lanes at all times unless special space is provided for midday loading. Contra flow lanes may be provided in the interior lane offset one lane from the curb in places where delivery and service vehicles must use the curb lane. This improves the ability to provide access to adjacent properties and improves pedestrian safety, although it requires an extra lane of road space. Such a treatment was installed on Sansome Street in downtown San Francisco in 1997. Because pedestrians will be conditioned by the appear- ance of one-way traffic operation, precautionary measures are 3-12 necessary to reduce the probability of accidents, especially when the lanes are first installed. Accordingly, special signs may be needed at major pedestrian crossings. Buses should operate with their headlights on at all times so they can be seen more easily by pedestrians. This method of operation is used along Spring Street in Los Angeles. Pedestrian safety can be improved by (1) strict enforce- ment of “jay-walking” ordinances, (2) signage and marking that warns pedestrians to “look both ways” at designated cross- walks, (3) special visual or audible warning devices installed on contra flow lane buses, and (4) a special yellow stripe 1 to 2 feet wide with “bumps” for pedestrians who are sight impaired and a warning message painted on the sidewalk adjacent to the curb. 3-2.4.2. Assessment Contra flow lanes retain existing bus routes when new one- way street patterns are instituted, allow new bus service on existing one-way streets, utilize available street capacity in the off-peak direction of flow, and permit passenger loading on both sides of one-way streets, thereby increasing curbside bus loading capacity. Buses are removed from other traffic flows and are not affected by peak-hour queues at signalized Recovery Lane Recovery Lane Queue Bypass Queue Bypass Buses and Right Turns extend beyond limits of queue. Queue Bypass for buses Barrier Right Turn Lane APPROXIMATE SCALE (FEET) 0 20 40 60 80 100 1. Typical Condition 2. Special Condition - Northbound Left Turn and Eastbound Right Turn on special phase Figure 3-9. Queue bypass concepts.

3-13 accidents drop. When the lanes operate on a street that pre- viously was one way, an increase may occur, especially ini- tially. The predominant cause of accidents is the inability of crossing pedestrians to recognize a street’s “wrong way” operation. These individuals may scan for traffic in the gen- eral traffic direction when crossing and fail to look for con- tra flow bus traffic. These perceptual deficiencies occur because the design of contra flow facilities violates basic driver and pedestrian expectancy. From a BRT perspective, the lanes have several dis- advantages: (1) they disperse buses onto two different streets, thereby detracting from BRT identity; (2) passing stopped or disabled buses is difficult unless dual bus lanes are pro- vided; and (3) buses run “against” the traffic signal progres- sion, although this can be partially offset. 3-2.5. Concurrent Flow—Interior Bus Lanes There are situations where curb parking must be retained. In these cases, concurrent flow interior BRT lanes can be provided adjacent to the parking lane on both one-way and two-way streets. Examples of such lanes are found in downtown Ottawa and along Washington Street in Boston, where they serve the Silver Line BRT. Photo 3-B illustrates the part of Boston’s Silver Line running way where curb parking is retained. 42' - 48' 52' - 60' 62' - 66' 76' - 80' NOTES: Prohibit Right Turns from Bus Lane Whenever Possible Left Turns may be Prohibited where Traffic Conditions Warrant Prohibit Left Turns Figure 3-10. Concurrent flow curb bus lanes for two-way streets. Photo 3-A. Curb bus lane, Silver Line, Boston. intersections. The lanes provide a high degree of bus service reliability and identity. Contra flow lanes can allow direct bus routings with sav- ings in bus miles, hours, and operating costs. They are “self- enforcing” because the presence of violators is easily detected. Although they can be used along radial arterial street couplets, buses would operate counter to the established traffic signal progression, and this could limit BRT speeds. Contra flow lanes have a mixed accident history. When the lanes operate on a street that previously was two way, total

3-14 enforcement is essential because the lanes—unlike contra flow lanes—are not self-enforcing. 3-2.5.2. Assessment Interior bus lanes remove buses from curb lane conflicts with often illegally parked vehicles, provide for unrestricted access to adjacent properties, and do not affect left-turn access. Right turns can be permitted from the bus lane or provided in the curb lane by prohibiting curb parking on the intersection approach. Bus bulbs can be provided on the far side of inter- sections for stops and stations. The downside of interior lanes is that if parking is permitted (e.g., in the off-peak period), there may be conflicts with parking and/or idling cars. 3-2.6. Median Bus Lanes and Median Arterial Busways BRT can operate in the center of streets in median bus lanes or median arterial busways. Median lanes may be delineated by painted lines for exclusive bus use. Although median arte- rial busways are physically segregated from adjacent street traffic lanes, the running ways are sometimes used by street- cars and LRT. It can be a challenge to provide pedestrian access to stations and deal with left turns, whether they are used by BRT, streetcars, or LRT. Both median bus lanes and Add 2-3 feet in areas with heavy pedestrian flow Alternatively provide loading from highway lane side.** * Can also serve as bus bypass lane. Figure 3-11. Contra flow bus lane designs. Photo 3-B. Interior bus lane, Silver Line, Boston. 3-2.5.1. Design Features Concurrent flow interior lanes should be at least 11 feet wide and be clearly delineated by pavement markings, tex- ture and/or color. Figure 3-12 gives a rendering of interior bus lanes on a multilane street. It is desirable to provide left- turn lanes wherever space permits; this results in a minimum cross section of about 60 feet (without left-turn lanes) and a cross section of 70 feet when turn lanes are provided. The bus lanes can be delineated by special pavement colors. Effective

median arterial busways can provide attractive running ways and stations. The median bus lanes have continuous access, making enforcement difficult, but providing routes around disabled buses (e.g., back into mixed traffic). Segregated median arte- rial busways are easier to enforce and provide a clear sense of identity. Both facilities superimpose at least three- to four- lane-wide envelopes, including platforms at on-line stations and off-line on the available street space. When passing lanes for buses are provided—as in South American cities— additional street space is required. Photo 3-C illustrates the passing capabilities of the running ways used in the Bogotá TransMilenio system. The actual street envelope (curb-to- curb width) depends on (1) how many lanes must be reserved for general traffic on each side of the busway and (2) whether left turns can be prohibited at stations. 3-2.6.1. Background and Examples Perhaps the first median bus lane in the United States oper- ated along Washington Street in downtown Chicago from the early 1950s to the mid-1970s. Canal Street, in New Orleans, 3-15 NOTE 1: Left-turn lanes should be provided wherever possible NOTE 2: Stops should be long enough to accommodate peak requirements NOTE 3: Near-side right-turn lanes could replace parking lanes Figure 3-12. Interior bus lanes. is the best example of a median arterial busway. The “neutral ground” on this 140-foot-wide street was converted from streetcar to bus-only operation in 1966, although streetcar service is scheduled to resume in 2004. A section of Number Three Road in Richmond, British Columbia (a Vancouver suburb), has an arterial median bus- way (see Photo 3D). Cleveland is planning median bus lanes on Euclid Avenue (with an approximately 100-foot right-of- way) that will be separated from general traffic flow by a 1-foot rumble strip. Examples of median running ways are illustrated in Photo 3-E (the Rouen system) and Photo 3-C (median running ways on the TransMilenio system in Bogotá). 3-2.6.2. Operations Median arterial busways for BRT should have two-way operation. Reversible one-way lanes along two-way streets can be used in situations in which bus service is provided “inbound” in the a.m. peak and “outbound” in the p.m. peak (e.g., to/from Montreal’s “Pie IX” metro station), but these are unlikely situations for most BRT applications. The bus lanes should be used only by BRT vehicles, with local buses

3-16 imum width, and the higher values give the desirable mini- mum. Total curb-to-curb street widths generally range from 75 to 90 feet. In most situations, a 100-foot total width is desir- able to provide wider lanes and/or space for landscaping. Guidelines for the design of bus lanes are as follows: 1. A single-curb traffic lane without any provision for access should be provided for only one or two blocks when road space is seriously constrained. 2. Ideally, left turns should be prohibited in station areas and provided elsewhere. 3. Left turns from general traffic lanes should be discour- aged. When provided, they should be signal-controlled with special phases. 4. The “midblock” space within the busway, on each side of the median busway between the BRT running ways, could be devoted to bus passing lanes or parking. 3-2.6.4. Design Features The design of median arterial busways should be keyed to the available total curb-to-curb street width and the need for left turns and curb access. Figure 3-13 gives a conceptual design for a wide arterial boulevard that provides these func- tions. It also identifies desired treatment for turn lanes and bus stops, signal controls, pedestrian access, “escape” lanes, and cross-street closures. The following features are illustrated: 1. Buses may join the general traffic flow at busway ter- minal points; however, special signal controls will be needed where buses turn right or left. 2. Intermediate right-turn entry and exit points to and from the outer roadway can be provided via slip ramps where space permits. 3. Right-turn exits from the busway via slip ramps should be located a sufficient distance from downstream traffic signals to enable buses to safely merge and weave across the roadway to enter the outermost lane.Photo 3-D. Median arterial busway, Vancouver. using the outside roadways. However, when the total peak- hour, one-way bus volumes are less than 20 buses, both local and BRT service can use the lanes. 3-2.6.3. Design Envelopes The curb-to-curb width at stations should be based on the parameters listed below. Curb Access Lanes 8 feet each Travel Lanes 10 to 12 feet each Barriers 2 to 4 feet minimum Left-Turn Lanes 10 feet Two-Lane Busway 22 to 24 feet Station Platform (side) 8 to 10 feet Minimum curb-to-curb widths for typical design condi- tions are given in Table 3-6. They assume far-side bus stops offset on either side of intersections and near-side left-turn lanes where provided. The lower values give the absolute min- Photo 3-C. Median arterial busway, Bogotá. Photo 3-E. Median running way, Rouen, France, TEOR system.

3-17 TABLE 3-6 Minimal roadway envelopes for median arterial busways (curb to curb) Left Turns Prohibited Left Turns Provided Single Traffic Lanes Each Side No Parking With Parking Lane 64–68 68–74 74–78 78–84 Two Traffic Lanes Each Side 76–84 86–90 NOTES: Lower values for 8-foot loading platform, 2-foot separation, 18-foot parking plus travel lane. Higher values for 10-foot loading platform, 4-foot separation, 19-foot parking plus travel lane. Design Condition Minor Street intersections restricted to right turns M IN OR S TR EE T A Platform length should accommodate a minimum of two buses M AJ OR S TR EE T TRAFFIC SIGNAL BUS STOP BUS STOP FENCE FENCE TRAFFIC LANES BUSWAY TRAFFIC LANES150' R 150' R 16' 22' - 24' If buses turn from cross street to busway, stop line on busway should be 60 ft. from crosswalk. Buses turning at cross street should exit busway at least one block in advance of the intersection. A 8'-12' SW 30'-36' TRAFFIC LANE 12'-16' 24'-25' BUSWAY 2'-6' 10' L. TRN LANE 30-36' TRAFFIC LANES 8'-12' SW 124'-152' R/W Conflicts between left turns and busway traffic should be avoided Suggested Signal Phasing: A B C (SOURCE: Adapted from Levinson et al., 1975) Figure 3-13. Median arterial busway design for a wide roadway. 4. Traffic signals should control movements at crossing roads. Buses should move on the green phase for through traffic that is followed by the left-turn phase. (This sequence is essential to minimize same-direction bus- automobile crashes.) 5. Pedestrian access to the stations should be provided at signalized intersections. 6. Traffic signal–controlled, near-side, left-turn, storage lanes are shared with the far-side bus station platforms; special signal phases should be provided wherever left turns must be accommodated. 7. Bus stops located in the islands must have passenger protection, and fencing is desirable to channel pedes- trian entry and exit to intersection crosswalks. Most rights-of-way will require more limited space designs; however, the same basic principles apply. Figures 3-14a and 3-14b show more likely configurations. Figure 3-14a illus- trates a configuration with left-turn lanes, and 3-14b illustrates a configuration without left-turn lanes. These designs require total rights-of-way widths of 100 to 105 feet and 90 to 95 feet, respectively, assuming 10-foot-wide sidewalks. When left turns are prohibited, the busway is offset about 6 to 8 feet; this offset decreases as the width of the median island increases. However, such lateral offsets should be minimized. Physical separations may be provided by raised islands with mountable curbs. A minimum separation of 4 feet between the busway and adjacent travel lanes will provide refuge for pedestrians and space for signs. When space is extremely tight, channelization such as flexible posts placed in predrilled holes can be used. Far-side “transit” signal indications, such as those used for LRT lines, should indicate to bus drivers when they may proceed or must stop. This will minimize confusion to approaching motorists (see Chapter 4). Passenger loading areas for bus stops should be adequate for expected peak-hour bus flows. Generally, they should provide at least two loading positions (100 feet for regular buses and 140 to150 feet for articulated buses). Stops may be located either midblock or on the far side. They should be at least 8 feet wide; a 10-foot width is preferred.

Figure 3-15 shows the “staggered” station platform design used in South America. The design provides a center lane for express buses; its direction alternates, resulting in a three- lane running way envelope. 3-2.6.5. Indirect Left Turns Along arterial roads with wide median strips, “indirect” left turns can be provided to simplify intersection conflicts and traffic signal phasing. This treatment has applicability in growing suburban areas where new roadways are being developed and where BRT is being considered. The indirect- left-turn concept, as shown in Figure 3-16, is in effect along Canal Street in downtown New Orleans where buses run in the central “neutral ground.” It is also used extensively on highways with wide medians in Michigan, where benefits in capacity, travel times, and safety have been documented. The indirect-left-turn concept prohibits all left turns at intersections and replaces them with far-side “U” turns cou- pled with a right turn; these kinds of turns are also known as indirect left turns. The indirect left turn permits simple two- 3-18 phase traffic signal operations at intersections. The “U” turns move on the same phase as the cross-street traffic. To make pedestrian access to stations safe and convenient, the “U” turn channels should not be provided at intersections with stations. The “U” turns should be placed where they have minimal impact on BRT service. 3-2.6.6. Assessment Median arterial busways located in the center of the street eliminate the passenger loading, curb access, and right-turn problems associated with curb lanes. They can be readily enforced and provide a strong sense of identity in running ways (preferably specially colored pavement) and stations. They can be grade separated at major intersections where space permits to eliminate traffic signal delays. They do, how- ever, pose problems in dealing with left turns, and pedestrian access to stations is less attractive than with curbside stops. They also usually require total roadway rights-of-way of 90 to 100 feet. Such rights-of-way are not common in most North American cities. Figure 3-14a. Typical median arterial busway designs with left turns.

3-19 (SOURCE: Gardner et al., 1991) Bus stop Bus stop BUS BUS BUS BU S BU S BU S BUS Typical Bus Stop Layout, Avenida Cristiano Machado, Belo Horizonte, Brazil Typical Bus Stop Layout, Avenida 9 de Julho, Sao Paulo, Brazil˜ Figure 3-15. Typical South American median arterial busway. Figure 3-14b. Typical median arterial busway designs without left turns.

3-2.7. Bus Streets Bus streets or malls can provide early action cost-effective downtown distribution for both BRT and local buses. They may be warranted where high bus volumes traverse narrow streets or as part of downtown revitalization proposals. Bus streets or malls may include the last block of an arterial street, a dead-end street at the end of several bus routes, a “bus loop” to change directions at major bus terminals, downtown bus malls, and bus circulation through automobile-free bus zones. Reserving streets for BRT and other buses can improve service speeds, reliability, and identity. Care must be taken to select streets that provide maximum advantage without hindering other traffic and access to adjacent premises. Gen- erally, bus streets should serve major concentrations of bus flow resulting from the convergence of individual lines onto a single street. They should penetrate the heart of the city cen- ter to provide easy, direct pedestrian access to major activi- ties. They provide logical passenger distribution for BRT run- ning ways on radial arterials or freeways, and they should be integrally tied to pedestrian mall development. 3-2.7.1. Rationale Bus streets clearly identify transit routes, and they are easy to enforce. They enable buses to pick up and drop passengers at places where shopping and business activity is at the high- est level. Bus streets are found in several U.S. cities and are used extensively throughout Western Europe. Examples in the United States include the Fulton Street Transitway in Brooklyn and the Nicollet Mall in Minneapolis. Bus streets increase walking space for pedestrians and waiting space at bus stops and can be ideal locations for off- board fare collection. They can be part of an overall down- town improvement program that is designed to stimulate activity and investment. But as their use by buses increases, they tend to become less attractive for pedestrians. Bus streets 3-20 are a compromise between giving buses unhindered passage to carry passengers close to their desired destination and pro- viding freedom of pedestrian movement. 3-2.7.2. Property Access Bus streets should incorporate curb loading zones for off- peak service vehicles when the necessary service cannot be provided from intersecting streets or off of the street. When other options are not practical, pickups and deliveries can be permitted from the bus streets when the bus traffic is low (i.e., night hours). Access to parking garages is a constraining factor that may require allowing automobiles on short discontinuous sections of street. Such an arrangement is incorporated in Portland Oregon’s dual lane, one-way, Fifth and Sixth Avenue bus streets where automobiles must turn off at the first cross street after leaving the parking garage. 3-2.7.3. Design Features Bus streets should provide passing opportunities around stopped buses when bus flows are heavy, the distances involved are more than 1⁄2 mile, and both BRT and other buses use the street. Stopping positions for BRT should be separated from those for local buses, but walking between them should be easy. Illustrative designs are shown in Figure 3-17. Bus streets usually are 22- to 24-foot two-way roads. This configuration is adequate when there are less than 50 peak-hour buses one way. When there are more than 60 buses per hour, it is desir- able to provide passing opportunities at stops. The stops may either lie near-side or far-side and should accommodate at least three articulated buses. When blocks are closely spaced, the stops may extend an entire block; however, designs should limit the passing opportunities to one lane. In cases of very 1 2 1/4 - 1/2 mi le BRT Signal Phasing at Locations A. B. C. D. Stat ion A B C D 120' Min - + Figure 3-16. Indirect left-turn concept for median arterial busways.

heavy bus volumes (e.g., over 90 buses per hour), dual lanes are desirable in both directions. Specific designs can include bus pull-outs, central medians at key points, widened side- walks, and passenger amenities. Care must be taken to ensure that other traffic is not unduly impacted and that parallel routes are available for displaced traffic. When the length of a bus street is less than three or four blocks, it may be feasi- ble to eliminate cross vehicular movements if traffic flows on cross streets are low. 3-2.7.4. Operations Bus streets generally should operate at all times. However, during late evening and overnight periods, when bus flows are very light or there is no bus service, other vehicles could use the bus lanes. Operations and service design are described more fully in Chapter 8. 3-3. OFF-STREET RUNNING WAYS Off-street BRT running ways are desirable in “line-haul” BRT operations to permit high speeds and to minimize traffic interferences. A desirable goal is to provide as much BRT route mileage as possible in reserved lanes or dedicated busways. Rapid and reliable BRT service is best achieved when buses operate in busways or reserved lanes on freeways. Locations in order of desirability are (1) separate right-of-way, (2) one 3-21 side of freeway, and (3) within freeway medians. A major issue with freeway medians is poor pedestrian access to sta- tions and the difficulty in integrating them with their sur- roundings to promote transit-oriented development. Busways have the advantages of better penetration of markets, a close relationship of stations to surrounding areas, and a stronger identity. Facilities in freeway corridors (reserved bus lanes) may be easier to develop because rights-of-way are already available. BRT use of freeways will benefit from bus-only ramps to the BRT facility and metered ramps with bus bypass lanes. These ramps have the dual benefits of reducing bus delays and/or improving main-line flow. Other HOVs could also use the bypass lanes. 3-3.1. Busways Dedicated, often grade-separated busways provide the most attractive running ways for BRT. Busways permit fast, reliable bus operations that are free from traffic interference and afford speeds comparable to those provided by rail rapid- transit lines. They provide a strong sense of identity and can achieve collateral land development benefits. Busways provide (1) line-haul BRT services to city cen- ters, (2) BRT service that extends rail transit lines, and (3) short bypasses of major congestion points. They segre- gate buses from other types of traffic, and they include ancil- lary passenger-bus interchange and parking facilities. They NOTE: If over 90 buses each way, dual-width lanes may be desirable. 22' 11'66' MIN 33' MIN 66' MIN 22' MIN 22' 22' 22' MIN 24' DESIRABLE BUS STOP BRT STOP 11' 22' OTHER BUSESBRT BRT STOP OTHER BUS STOP 60-90 PEAK-HOUR BUSES EACH WAY 20-60 PEAK-HOUR BUSES EACH WAY Figure 3-17. Typical bus street designs.

may be constructed at, above, or below grade (as in tunnels), either in separate rights-of-way or within freeway corridors. They may be designed as “open” systems that let buses enter or leave at intermediate points or as “closed” systems in which buses operate only on the busway. They may be fully or par- tially grade separated or entirely at grade. 3-3.1.1. Planning, Location, and Configuration Busways should form the backbone of the BRT system whenever suitable corridors are available and a sufficient number of buses is available to establish a BRT “presence” along the corridor. Busways should save at least 5 minutes of travel time over alternate bus routings, on average. They are also desirable where freeways are congested and where physical, social, and/or environmental conditions preclude major road expansion. Downtown busway development (e.g., bus tunnels) may be appropriate when peak-hour bus speeds are less than 5 to 6 miles per hour, when the congested area extends for more than a mile, and when surface-street priority options cannot substantially improve speeds. 3-3.1.2. Cost-Effectiveness The number of passengers along the busway and the esti- mated travel time savings should bear a reasonable relation- ship to the development costs incurred. Ideally, the travel time benefits, measured in the value of time saved for bus passengers, should exceed the annualized development and operations and maintenance costs. Typical cost-effectiveness values for busways and bus tunnels are shown in Table 3-7. 3-3.1.3. Location Options Busways may be built on separate rights-of-way, along- side freeways, or within freeway medians. Locations in order of desirability are (1) separate right-of-way, (2) one side of a freeway, and (3) within freeway medians. 3-22 TABLE 3-7 Busway riders needed to produce a net benefit Time Savings, Min / Mile Busway Cost (Millions of Dollars per Mile) 1 2.5 5 7.5 10 25 50 11,000 27,500 55,000 4,000 11,000 22,060 22,000 5,500 110,000 1,500 27,000 7,300 Bus Tunnel 200 300 220,000 330,000 88,000 132,000 44,000 66,000 29,300 44,000 NOTES: Typical values are underscored. Capital recovery: 50 years @ 5% interest, 300 days per year, $10/hour value of time. Photo 3-F. East (MLK) Busway, Pittsburgh. Busways located on their own right-of-way can penetrate high-density residential and commercial areas, traverse city centers and other major activity centers, and allow easy bus and pedestrian access to stations. Access points can be developed simply. Constraining factors include land avail- ability, time to develop, and costs. Sometimes busways can be located along active or aban- doned rail lines, as in Miami and Pittsburgh (shown in Photo 3-F) and in the case of the proposed New Britain– Hartford Busway. This can reduce land acquisition costs, community impacts, and construction periods. However, right-of-way availability should be balanced with proxim- ity and access to key transit markets. Many rights-of-way are geographically removed from residential and employ- ment concentrations and offer limited opportunities for transit-oriented development. Exclusive busways within a freeway corridor may be located either within the median or along one side of the free-

Photo 3-G. Busway adjacent to freeway, Brisbane, Australia. ( ) Figure 3-18. Busway located alongside freeway at interchange. 3-23 way. Both have the advantages of using existing publicly owned land and operating in reserved lanes and mixed traf- fic at the outer ends of the busway. Busways located along one side of a freeway (such as the South East Busway in Brisbane, shown in Photo 3-G) provide a better identity, easier access to stations, and sim- plified intermediate and terminal access points; they are also conducive to transit-oriented development along one side, as has occurred in Ottawa. However, they may require grade separations at freeway interchanges to avoid conflicts with ramps. When freeway corridors are wide enough, the busway can be located beyond the interchange; when rights-of-way are constrained, the busway may have to be grade separated at all ramps. Examples of possible configurations are shown in Figure 3-18. For diamond interchange configurations, the busway could be located outside of the interchange area; for other configurations, separate structures may be required. Busway locations within a freeway median are desirable where freeways are suitably located and costs make it essen-

tial to minimize rights-of-way. They work best if the major- ity of demand is to/from a single location (e.g., a CBD), and there are few attractions at intermediate stations. These treat- ments are relatively simple to achieve, usually involve lower capital costs, and have minimum impact on ramp or inter- change geometry. However, complex intermediate bus access points may be needed to avoid weaving across the main free- way lanes. Pedestrian access to stations may be difficult, and direct across-the-platform bus interchange (from BRT to other buses) is not possible. Finally, the identity and image of the busway can be overwhelmed by the freeway, making it dif- ficult to use facility and stations to promote transit-oriented development. 3-3.1.4. Configuration and Operating Concepts Busways should be straight, penetrate high-density areas, and minimize the number of branches. Figure 3-19 shows desirable and undesirable busway configurations. Some configuration and operating concepts for busways are the following: 1. Radial Character. Busways serving a CBD should radiate outward from the city center and ideally pass through it. Cross-town lines should be developed only when clearly warranted by land use and travel densities. 2. Market Penetration. Busways should penetrate high- density residential areas and provide convenient down- town distribution. They should serve both high-density (urban) and lower-density (suburban) markets. 3. Through Service. Through routes are preferable when- ever operating and demand conditions permit. Through service increases passenger convenience and simplifies movements in the city center. However, because of schedule variances, through service may not always be advisable, especially on long routes. 4. Simplified Route Structure. Busways should have simple, understandable route patterns. The number of branches should be minimized and be consistent with needs to promote route identity, maintain frequent ser- vice, simplify station berthing requirements, and keep dwell times low. 5. High Operating Speeds. Portal-to-portal bus speeds between the city center and outlying areas should be comparable to automobile speeds. This can be achieved by providing all-stop and express service along bus- ways. Good geometric design and sufficient distance between stations are important for achieving high operating speeds. 6. Station Access. Busway stations should be accessible by foot, bicycle, automobile, or bus. They should be placed at major traffic generators and intersecting bus lines. Park-and-ride facilities should be provided in 3-24 outlying areas where most access is by automobile. Bicycle locking facilities should be provided where space is available. 7. Station Spacing. Station spacing should vary inversely with population density. Close station spacing (1⁄4 to 1 mile) should be provided where passengers can walk to stations; wider station spacing is feasible where peo- ple ride buses to stations (1⁄2 to 1 mile) or drive to sta- tions (1 to 3 miles). The need for stations is diminished when buses can leave busways for local collection and distribution. To facilitate downtown, off-street, pas- senger distribution, it is desirable to provide at least three stops at 1⁄4- to 1⁄3-mile intervals. This will avoid concentrating all boardings and alightings at one loca- tion with attendant increases in bus dwell times. 8. Convenient Transit, Pedestrian, and Automobile Inter- change. Park-and-ride facilities and, in some cases, bus transfer facilities should be provided in outlying areas where population densities are too low to gener- ate sufficient walk-in patronage. 9. Maximum Driver Productivity. The number of peak- hour passengers per bus driver should be maximized through (1) service configurations that allow multiple trips in peak hours, (2) use of high-capacity (e.g., artic- ulated) vehicles, and (3) high speeds. 10. Downtown Distribution. BRT service in the city cen- ter may be provided by bus streets or bus lanes or in off-street bus tunnels or busways. The goal should be to provide unimpeded through service wherever pos- sible (see Figure 3-20). However, in some cases, ter- minals can be provided at the edge of the CBD, where walking distances to/from most trip destinations are less than 5 to 10 minutes. 3-3.1.5. Design Criteria and Guidelines Busway design should permit safe and efficient operation. Some guidelines for busway design are the following: • Busway designs should enable buses to pass stopped or disabled vehicles without encroaching on the opposite direction whenever possible. This can result in cross sections ranging from 48 to 80 feet at stations including platforms, medians, stopping lanes, and through lanes. • Busways could be designed for possible future conver- sion to rail or other fixed guideway transit in terms of horizontal and vertical curves, drainage requirements, and so forth. • Busways should operate normal flow (with shoulders provided wherever possible), special flow (with a cen- tral shoulder or passing lane), or contra flow (with a central shoulder passing lane). Normal flow designs are the simplest and most common. Contra flow configura-

3-25 HIGH-DENSITY AREA CBD CBD HIGH-DENSITY AREA CARRY SPECIAL R/W BEYOND FREEWAY RING PARK-RIDE PRESERVE R/W FOR FUTURE EXTENSION DIRECT FREEWAY ACCESS TRAVERSE CBD PENETRATE HIGH-DENSITY AREA EXCESSIVE SERVICE VARIETIES NO BUSWAY FREEWAY ACCESS TERMINAL ECCENTRIC TO CBD, REQUIRING SECONDARY DISTRIBUTION POOR SERVICE THROUGH HIGH- DENSITY AREA STATION TERMINAL BUSWAY BUS ROUTE ON SURFACE STREET FREEWAY FREEWAY WITH BUS LANE LEGEND DESIRABLE UNDESIRABLE (SOURCE: Levinson et al., 1975) Figure 3-19. Desirable and undesirable busway configurations.

tions permit common center-island station platforms that minimize the number of station stairways, supervision, and maintenance requirements. However, they require crossovers at beginning and end points or vehicles with doors on both sides. Typical criteria drawn from contemporary highway and busway practice are given in Table 3-8. The criteria are given for two basic types of busways. Class 1 busways are com- pletely grade separated and support service levels comparable to rail rapid transit. Examples include Adelaide, Ottawa, and Pittsburgh. Class 2 busways are partially grade separated or at grade and support service levels similar to LRT lines. Examples include the South Miami-Dade Busway and the New Britain–Hartford Busway. Busway Use. Transit buses of more than 18 passengers and operated by professional drivers should be allowed to use busways (and contra flow freeway bus lanes). Busways should permit use by emergency vehicles—ambulances, fire trucks, police cars—and by maintenance vehicles. Design Vehicle. Roadway geometry should be governed by the performance and clearance requirements of standard 40- to 45-foot buses and 60- to 70-foot articulated buses. Joint-use guideways should be wide enough to accommodate LRT vehicles. Loads. Structures should be designed to accommodate AASHTO H20-S-16-44 live loads. Design Speeds. Desirable design speeds are 70 miles per hour for Class1 busways, 50 miles per hour for Class 2 3-26 busways, and 40 miles per hour for bus ramps. Minimum design speeds are 50, 40, and 30 miles per hour, respectively. A busway may incorporate sections having different design speeds, but the changes should be few and gradual. Alignment. Safe stopping sight distances, horizontal cur- vature, and vertical curvature should reflect AASHTO prac- tice. Each is keyed to design speeds. Table 3-8 shows repre- sentative values for the mid-range speeds. When future convertibility is a factor, the minimum radius should be at least 250 feet. Cross Slopes. Pavement cross slopes should be between 1.5 and 2%. Slopes on shoulder and border areas can be up to 4 and 6%, respectively. Gradients. Busway grades should be less than 6% when future conversion to rail is anticipated and 9% otherwise. Clearances. Minimum vertical clearances of 13 to 14.5 feet should be provided. Where rail rapid transit is anticipated, vertical clearance will be governed by the future system needs. Lateral clearances (overall) should be at least 6 feet for busways. However, under restricted conditions, minimum 1-foot clearances can be provided along each side of Class 2 busways and along ramps. Center medians, when used, are limited to station areas. Envelopes. Busway envelopes include the travel lanes, center median (if used), shoulders, and outside curbs/parapets along elevated or depressed sections. Many existing Class 1 and Class 2 busways do not use center medians. This has the advantage of allowing passing of a slow or stopped lead- CBD BUS LANES CBD BUS TUNNEL BUSWAY BUSWAY BU SW AY Figure 3-20. Through-service concepts with CBD distribution.

ing bus. These envelopes may vary based on local conditions, although they should be wide enough to permit safe and effi- cient operation. Envelope requirements are the following: • Lanes should be 12 feet wide. However, 11-foot lanes are acceptable in constricted areas, at terminals, and along Class 2 busways. • Shoulders are desirable to accommodate disabled buses and should be provided whenever space permits. Full- width (8- to 10-foot) shoulders are desirable, although narrower shoulders may be used when space is con- strained. Shoulders may be reduced or omitted along elevated structures, in tunnels, and in other situations in which right-of-way is limited. 3-27 Pavement Widening on Busway Curves. Additional lateral width is needed on curves for the maneuvering and overhang of various parts of the buses. Pavements should be widened 1.5 to 2 feet on curves 1,000 feet or less, depending on design speed and busway width (see Table 3-9). These values accommodate a 40-foot-long, 8.5-foot-wide design vehicle, but they will also accommodate a 60-foot articulated bus that requires similar maneuvering space. Ramps. Class 1 busway ramps should be designed for speeds of 30 to 40 miles per hour. Class 2 busways should be designed for speeds of 20 to 30 miles per hour. Lanes should be 12 to 14 feet wide and shoulders should be 10 feet wide. A total width of 22 to 24 feet is desirable, but a total width may TABLE 3-8 Busway design criteria DESIGN PARAMETER CLASS 1 BUSWAY FULLY GRADE SEPARATED CLASS 2 BUSWAY PARTIALLY GRADE SEPARATED OR AT GRADE DESIGN SPEED (MPH) 50–70 30–50 ALIGNMENT (MID-VALUES) (FEET) Stopping Distance 640 300 Horizontal Curvature 200 125 Desirable Minimum 1350 500 Minimum—Convertible to Rail 250 250 Minimum—Convertible to Light Rail 100 100 Absolute Minimum 100 100 Super Elevation 0.06 0.08 GRADIENTS (%) Maximum (Convertible to Rail) 3–4% 3–4% Maximum 3–5% 4–6% Minimum 0.3% 0.3% CLEARANCE (FEET) Vertical 14.5(a) 14.5(a) Lateral (each side) 6 2–6 ENVELOPE (TYPICAL) (FEET) Lane Width 13–13.5(b) 11–12 Shoulders 8–10 2–6 Envelope 42–47 26–36 ENVELOPE (SPECIAL) (FEET) Elevated 30–36 30 Tunnel (Minimum) 31–32 31–32 NOTES: (a) should be 16 feet where overhead collection (for bus or rail) is planned. (b) 12-foot lanes with 2–3 foot paint separator. TABLE 3-9 Pavement widening on two-way, two-lane busway curves ROADWAY WIDTH 24 FEET 22 FEET Design Speed, MPH Design Speed, MPH RADIUS 30 40 50 60 70 30 40 500 feet 1.5 2.0 2.5 3.0 750 feet 1.0 1.0 1.5 2.0 2.0 1,000 feet 0.5 1.0 1.0 1.5 1.5 2.0 2,000 feet 0.0 0.0 0.0 0.5 1.0 1.0 1.0 3,000 feet 0.0 0.0 0.0 0.0 0.5 0.5 1.0 4,000 feet 0.0 0.0 0.0 0.0 0.0 0.5 0.5 NOTE: Values less than 1.5 may be disregarded. SOURCE: Levinson et al., 1975.

be narrower for limited distances in restricted situations. Ramp exit and entrance speed-change design should follow AASHTO criteria when possible. 3-3.1.5.1. Bus Tunnels Suitable provisions for tunnel ventilation are essential. Stations may have “conventional” at-curb platforms (high or low level) or may use a transparent wall or door. These trans- parent doors, which separate the passenger waiting area from the busway lanes and reduce noise levels, open only when the buses arrive. Such doors are used in the downtown Brisbane bus tunnel. Electric trolley buses and dual mode buses are used in Seattle’s bus tunnel and will be used in Boston’s Silver Line tunnel. Hybrid diesel-electric buses are also being introduced that will allow tunnel operations under battery power. Tun- nels for these newer “improved air quality” buses require less ventilation capacity than is required for conventional buses. Vertical clearances should be adequate to accommodate the trolley poles and overhead wires, as appropriate. Suitable facilities for moving, storing, and passing dis- abled buses should be provided. This is accomplished by pro- viding a third lane at stations in Seattle’s tunnel and by pro- viding several “storage areas” between opposing directions in Boston’s Silver Line tunnel. 3-3.1.5.2. Sample Cross Sections Illustrative cross sections are shown in Figures 3-21 and 3-22. Figure 3-21 shows typical busway cross sections for locations between stations. Ideally, two 12-foot lanes should be separated by a 2- to 3-foot painted median and by 8- to 10-foot shoulders. This results in a 42- to 47-foot envelope. Under restricted situations, the center painted median can be 3-28 MINIMUM 28 - 36 FEET 12' 2'-6'2'-6' 12' DESIRABLE 42 - 47 FEET 12' 8'-10'8'-10' 2-3' 12' Figure 3-21. Typical busway cross sections. eliminated, and the shoulders can be reduced to 2 to 6 feet. This results in a 28- to 36-foot envelope. Examples of this busway design are found in Miami, Ottawa, and Pittsburgh. Envelopes at stations are wider to allow passing lanes for buses and facilities for passengers. Figure 3-22 shows mid-station busway cross sections within a freeway median. In all designs, a barrier median sep- arates the busway from the freeway lanes. The “desirable” treatment shown in Design A provides a 42- to 47-foot enve- lope, whereas the minimum design, Design B, has 2-foot rather than 8- to 10-foot shoulders and results in a 28-foot envelope. Designs C and D show busway lanes separated by 10-foot and 14-foot painted medians, respectively. Both designs have 2-foot shoulders. The resulting envelopes are 38 to 42 feet. This concept has not been applied in practice. 3-3.1.5.3. Stations Busways are typically widened at stations to enable express buses to pass buses making stops. Generally, the number of busway lanes is increased from two to four, and the shoulder areas are eliminated. An alternate concept, proposed along the New Britain–Hartford Busway and used on several median arterial busways, provides a single passing lane and staggered station platforms, reducing the overall width (including lanes, medians, and platforms) to roughly 50 feet. Further details on station guidelines are provided in Chapter 5. 3-3.1.5.4. Busway Access Special access treatments are required where busways begin, end, or branch and where buses enter and leave at intermediate access points. Providing this access is straight- forward when busways operate on separate rights-of-way. It becomes more complex when busways are located within freeway medians or alongside freeways. In this case, access can be provided directly onto freeway lanes, or by means of special structures to cross streets. Busway access options include (1) at-grade slip ramps to freeways, (2) direct ramps to cross streets, (3) flyover ramps, and (4) at-grade, bus-only connections to other busways or streets. In special situations, as in Houston, special “T” ramps from busways in freeway medians to off-line stations can be provided (see Photo 3-H). Location of access points should reflect street geometry and likely bus routes. Traditional intersection and freeway design standards should be applied per AASHTO and other design and capacity guidelines. Examples of busway freeway connections at the starting and ending points for median and side-aligned busways are shown in Figure 3-23. Transitions to freeway travel lanes are made by high-speed merging and diverging movements. Access to cross streets is by means of a standard “T” ramp.

3-29 2' 24'-25' 8'-10'8'-10' 42-45 FEET FREEWAY DESIRABLE DESIGN A 24' 2'2' 28 FEET FREEWAY MINIMUM DESIGN B FREEWAY FREEWAY 14' 12'12' 42 FEET FREEWAY DESIRABLE DESIGN C FREEWAY 2' 10' 12'12' 38 FEET FREEWAY REDUCED DESIGN D FREEWAY 2' 2' Figure 3-22. Busway cross sections within freeway median. BUSES ALONGSIDE FREEWAY BUSWAY ON SPECIAL R/W FREEWAY FREEWAY BUSWAY IN FREEWAY MEDIAN BUSWAY IN FREEWAY MEDIAN CR O SS S TR EE T FREEWAY NOTES: 1. Minimum outside radius for Busways - 50 ft. 2. Minimum lane width for Busways: Through Lanes - 12 ft. Left Turn Lanes - 11 ft. (SOURCE: Levinson et al., 1975) Figure 3-23. Busway and freeway transitions.

Figure 3-24 illustrates busway transition concepts for side- aligned busways connecting with ramps at diamond and partial-cloverleaf interchange ramps. Figure 3-25 provides transition details for busways on their own right-of-way or within the median of a freeway. Figures 3-26 and 3-27 give examples of at-grade bus ramp connections. Generally, a 1-in-50 transition of through lanes around left-turn lanes is required. Stop signs or traffic signals should control move- ments and give preference to main line busway movements. It is estimated that the at-grade controls can effectively man- age bus flows of 3 to 5 buses per minute (180 to 300 buses per hour). 3-3.1.5.5. Class 2 Busways Class 2 busways combine both grade-separated and at- grade intersections. Examples include the South Miami-Dade Busway and the Runcorn Busway. They are similar to arte- rial median busways except that they should operate on sep- arate rights-of-way. A Class 2 busway concept is shown in Figure 3-28. Class 2 busways can utilize narrow rights-of-way in urban and suburban areas. When streets and land developments fol- low rectangular grids, rights-of-way approximately one lot wide can be acquired, and the busways can be developed at grade. Minor streets should terminate in loops or cul-de-sacs, and grade crossings should be signalized. The busways should be separated from parallel arterial roadways by at least 660 feet. The separation will allow signal controls along intersecting streets to operate independently. Bus-actuated signals at crossing roads should give preferen- tial treatment to buses (advanced green, retarded red cycles); however, this may not be practical when busways intersect heavily traveled crossroads. In such cases, bus actuations should come about in a specified period of the overall back- ground signal cycle. Class 2 busways also have applicability in new commu- nities and large planned-unit developments. Busways can 3-30 penetrate residential developments, with streets and parking located along the outside perimeter. This will reduce walking distance to bus stops and help achieve a synergistic transit– land use relationship. 3-3.1.5.6. Guided Busways Mechanically guided busways operate in Adelaide, Aus- tralia; Leeds, United Kingdom; and in Nancy and Caen, France. In Adelaide and Leeds, special guideways provide curbing on each side of single-line “tracks,” and busway track width is sized to fit the distances between three sets of side guidance wheels on each side of the bus. The wheels, which are connected to the power steering system, bear against the concrete curbs. A typical cross-section view is shown in Figure 3-29. The 20-foot section is several feet less than sections required for conventional busways. Specially fitted standard buses can be used. Their size can vary as long as the horizontal guide wheels are uniformly spaced. Buses can enter the guided busway at 25 miles per hour and operate at a cruising speed of about 60 miles per hour. They can dock precisely at stations. In Nancy and Caen, a central guidance track is contacted by a metal guidance wheel that steers the vehicles. 3-4. FREEWAY RUNNING WAYS Freeway running ways can provide a cost-effective basis for BRT. They can speed bus service, improve bus reliability, and also provide a strong sense of identity where stations are provided. They can be used by conventional all-day, high- frequency routes and peak-hour nonstop service, depending on specific facility design and service requirements. Running way types vary in their placement along the roadway, number of lanes provided, direction of travel, and type of separation. Table 3-10 summarizes the various freeway-related running ways and gives their general applic- ability for BRT. 3-4.1. Eligible Vehicles A major policy decision is whether running ways should be used only by buses or by other HOVs as well. Initial instal- lations in the United States were used only by buses. How- ever, most freeway running ways currently are shared with other HOVs. This practice maximizes throughput in terms of person miles per hour, and it avoids the “empty lane syndrome” in places where bus volumes are low. To avoid impacting the lane’s effectiveness for BRT, a minimum level of service can be specified. For example, whenever the level of ser- vice drops below level “C,” the HOV criteria for persons per vehicle can be adjusted or pricing techniques (such as high- Photo 3-H. “T” ramp in Houston.

3-31 NOTES: 1. Minimum outside radius for Busways - 50 ft. 2. Minimum lane width for Busways: Through Lanes - 12 ft. Left Turn Lanes - 10 ft. BUSWAY ALONGSIDE FREEWAY BUS ROUTING: FREEWAY BUSWAY BUS STOP "STOP" OR "YIELD" BUS STOP BUS STOP LEFT TURN LANE, BUS ONLY FREEWAY (SOURCE: Levinson et al., 1975) NOTES: 1. Minimum outside radius for Busways - 50 ft. 2. Minimum lane width for Busways: Through Lanes - 12 ft. Left Turn Lanes - 10 ft. BUSWAY ALONGSIDE FREEWAY STOP OR YIELD BUS STOP ACTUATED SIGNAL LEFT TURN LANE BUS ONLY BUS STOP Figure 3-24. Busway-freeway transitions at interchanges.

3-32 (SOURCE: Levinson et al., 1975) BUSWAY IN FREEWAY MEDIAN ACCESS FROM FREEWAY 400' MIN. 400' MIN. BUSWAY IN FREEWAY MEDIAN ACCESS FROM CROSS STREET BUSWAY ALONGSIDE FREEWAY OR IN SPECIAL R/W ACCESS FROM CROSS STREET 75' MIN. 75' MIN. Figure 3-25. Busway access. (SOURCE: Levinson et al., 1975) NOTEs: 1. Where high-speed operations are destined on both main line and branch route, grade-separate junction should be used. 2. With minor variations, illustrations are also applicable to special flow busways. 3. Through lanes should utilize curves in transition areas, using radii appropriate for design speed. Figure 3-26. Busway junctions.

3-33 (SOURCE: Levinson et al., 1975) Figure 3-27. Example of layout for busway intersection. (SOURCE: Levinson et al., 1975) Figure 3-28. Class 2 busway concept.

TABLE 3-10 Freeway facility options for BRT BRT APPLICATION FACILITY CONVENTIONAL ALL-DAY BRT SERVICE PEAK-HOUR COMMUTER EXPRESS SERVICE (NO STOPS) Exclusive Two-Way Facilities (Busways)1 Common Shoulder Separation ✓ ✓ Physical Barrier Separation ✓ ✓ Exclusive Reversible Roadways Single Lane ✓ Dual Lanes ✓ Concurrent Flow Bus Lanes Right Outside Lane (or Shoulder) Short sections where interchanges are widely spaced. Median Lane ✓ Contra Flow Bus Lanes Single Lane ✓ Dual Lanes ✓ Queue Bypass Lanes Bus-Only Ramps Complements other running ways. Bus Bypass of Metered Entrance Ramps Complements other running ways. NOTES: 1 See Section 3-3.1 of this chapter. SOURCE: Adapted from Texas Transportation Institute et al., 1998. 3-34 (SOURCE: Richards, 1990) Figure 3-29. Guided busway and conventional busway sections.

3-35 3-4.3. Design Guidelines Running way design should be consistent with established standards for the adjacent general purpose freeway. A 70-mile- per-hour design speed is common, although lower speeds are sometimes used. Speeds should also reflect the type of running way. Table 3-11 gives illustrative design speeds for “desir- able” and “reduced” conditions. 3-4.4. Exclusive Two-Way Facilities Two-way bus roads (busways) within the freeway median can be physically separated from general purpose traffic lanes by a common shoulder (e.g., the San Bernardino Transit- way) or by a physical barrier. They can provide complemen- tary facilities such as stations, bus-bus interchange, and park- and-ride lots. 3-4.5. Exclusive Reversible Roadways Reversible roadways, which are typically separated from freeway lanes by islands or barriers, are provided in several cities for use only by HOVs for peak-period, peak-directional trips. These lanes also can be used for commuter express buses that run nonstop and then leave the lanes via special access points to provide park-and-ride lots with bus service or provide local street distribution service. Examples of such facilities include the Shirley Highway in Northern Virginia (I-395), initially a bus-only road; the I-15 Express/high occupancy toll (HOT) lanes in San Diego; and the I-25/HOV lanes in Denver. The largest system is found in Houston where a “Transitway” system that is over 100 miles in length operates in five radial corridors. These exclusive roadways may include intermediate reversible access ramps to streets and park-and-ride lots. Manual and automated methods for opening, reversing, and closing the exclusive roadways are used. Examples of cross sections are shown in Figure 3-30. A min- imum barrier-to-barrier envelope of 20 feet is shown, although this may require adjustments to mirrors to allow for passing capability. A 24- to 28-foot (minimum) envelope to facilitate passing disabled buses is desirable. Figure 3-31 gives an exam- ple of the “T” ramps used on the Houston Transitway system. The reversible ramps provide direct access to park-and-ride lots and bus terminals. Key design features include (1) acceleration TABLE 3-11 Typical design speeds for running ways within freeways Typical Design Speed Type of Running Way Reduced Desirable Barrier separated 80 km/h (50 mph) 120 km/h (70 mph) Concurrent flow 80 km/h (50 mph) 100 km/h (60 mph) Contra flow 40 km/h (30 mph) 80 km/h (50 mph) SOURCE: Fuhs, 1990. occupancy/toll lanes) can be considered. Other considera- tions for bus/HOV shared facilities include the following: 1. Placement of HOV lanes within the freeway may make it difficult to provide on-line stations unless they are considered in the original freeway design, 2. Buses stopping at stations can be delayed when they reenter the HOV lanes, and 3. Reliability may be less certain than with exclusive bus- only running ways. Where nonstop “commuter express service” is provided (as in Houston), the running ways may be shared with car pools and van pools with off-line BRT stations accessed from the facility with “T” ramps. 3-4.2. Planning and Operating Considerations Planning and operating considerations for running ways are listed below. Both median and right-side bus lanes have proven operable. Median lanes are removed from ramp conflicts at interchanges and can allow special median access to cross- roads. However, they require careful design of access points to stations. Right-side lanes allow easy bus entry and exit. However, they result in frequent weaving conflicts, especially where crossroad entry and exit ramps are closely spaced. Bus lanes generally should extend at least 5 miles when buses run nonstop to achieve a time savings of 5 miles per hour or more. The principal exceptions are queue bypass lanes on approaches to major arterial intersections, freeways, or river crossings. Existing freeway lanes in the heavy direction of travel should not be converted to bus lanes. It is better to provide additional lanes so that existing traffic congestion is not worsened. Where a BRT commuter service (such as in Houston) operates on an HOV facility, it is essential that the service have its own access/egress ramps to the off-line transit stations and/or its park-and-ride facilities. Residential collection should be done without requiring buses to weave across general traffic lanes to enter and leave station areas. Standardization of freeway entrance and exit ramps to the right of the through traffic lanes permits the use of median lanes by buses either in concurrent (normal) or contra flow traffic. Dedicated bus entry and exit ramps to and from freeway median bus lanes or roadways should be provided without interfering with normal automobile traffic on the right-hand ramps and requiring buses to weave across the main travel lanes.

(SOURCE: Texas Transportation Institute et al., 1998) Figure 3-30. Examples of cross sections for one-lane busway in freeway median. 3-36 (SOURCE: Texas Transportation Institute et al., 1998) Figure 3-31. Example of reversible flow “T” ramp.

and deceleration lanes where the elevated ramps enter the main HOV roadway and (2) a 22- to 24-foot cross section for the single HOV lane, including a shoulder and travel lane. The Houston Transitway HOV lanes have several advan- tages: (1) they make use of available right-of-way within a freeway median; (2) they provide a cost-effective approach to adding peak-direction person capacity; (3) the physically separated lanes are self-enforcing; and (4) a sense of BRT identity can be provided. Because exclusive reversible roadways permit BRT service only in peak periods, they are best suited for peak-hour com- muter express runs rather than for all-day, multi-function BRT. 3-4.6. Concurrent Flow Bus Lanes Concurrent flow bus lanes may be located on the outside lanes or shoulders of the main travel lanes or located within the median lane. The outside lanes are appropriate where inter- changes are widely spaced, weaving conflicts are manageable, and buses traverse a small number of interchanges. They are used for outlying sections of the Ottawa Transitway, as shown in Photo 3-I. Median lanes are the most common HOV treat- ment. They are removed from entry and exit conflicts, but they require special facilities for bus entry and exit. Like the median barrier BRT options, they include adding lanes to the freeway cross section. The additional lanes may be provided by widening the roadway, narrowing existing lanes slightly, and/or reducing the inside shoulder. 3-37 (SOURCE: Texas Transportation Institute et al., 1998) Figure 3-32. Examples of cross sections for concurrent flow bus (or HOV) lane located on the outside of a freeway. Photo 3-I. Queensway Busway shoulder lane, Ottawa. Examples of cross sections are shown in Figures 3-32 and 3-33. Lanes should be 12 feet wide with 2- to 10-foot inside shoulders for median lanes and 4- to 10-foot shoulders for outside lanes. Both lane widths and shoulders may be reduced under special circumstances. The lanes are usually separated from the main travel lanes by a solid white lane line that is broken at locations where vehicles may enter or leave. A 1- to

3-38 4-foot separation from adjacent lanes is desirable where space permits. Normally, entrance to the concurrent flow lanes and exit from them is made from the main travel lanes. These should be located where merging and diverging movements are removed from interchange areas. Concurrent flow median bus lanes often have advantages of relatively low costs, quick implementation, and minimum right-of-way requirements. However, they are subject to fre- quent violations and require constant, intensive enforcement to minimize violations—especially when incidents occur in the general purpose lanes. Intermediate, on-line stations at the freeway level or cross-street level could be provided, but they would require sufficient right-of-way width at the cross-street locations. Therefore, their use has mainly been for short nonstop runs (perhaps as links in a more extensive system) or for express bus runs. The BRT identity of the sta- tions could be enhanced by using special colored pavements. 3-4.7. Contra Flow Bus Lanes Contra flow lanes for BRT operate in the off-peak direc- tion of freeways. They are an adaptation of reversible lane concepts applied to urban freeways for a half century. They are well suited for peak-period express (nonstop) bus runs inbound to the city center in the a.m. peak and outbound in the p.m. peak. Both single and dual contra flow lanes can be provided. Buses can use single contra flow lanes because (1) the bus lane traffic stream is homogenous, and there is no need for overtaking slower vehicles; (2) buses are highly visible to other drivers, especially when emergency flashers are used; (3) professional bus drivers are generally well trained, expe- rienced, and highly disciplined; and (4) bus lane volumes are relatively low, making the risk of a collision no greater than along an undivided urban arterial or rural highway. Several a.m. peak-period contra flow lanes operate in the New York–New Jersey metropolitan area. A single bus-only lane has operated on the New Jersey approaches to the Lincoln Tunnel (as shown in Photo 3-J) since 1970. On the Queens approach to the Midtown Tunnel (I-495), a single bus/taxi lane has been operated since 1971. A contra flow bus/HOV lane is provided on the Brooklyn approach to the Brooklyn Battery Tunnel (I-278). Each is heavily used, provides significant travel time saving for bus riders, and has a satisfactory safety record. (SOURCE: Texas Transportation Institute et al., 1998) Figure 3-33. Examples of cross sections for concurrent flow bus (or HOV) lane located on the inside of a freeway.

3-39 enough to permit buses to pass stalled vehicles (e.g., a 20- to 24-foot envelope), but this is not always practical. Therefore, careful monitoring of operations and provision for quick removal of disabled vehicles are essential. Travel lanes should be 12 feet wide, although 11-foot lanes have also been used. The lanes should have a 2-foot separa- tion from opposing traffic marked by plastic pylons (installed and removed each peak period), as is the case for each of the New York–New Jersey area lanes. Alternatively, the lane separation can be secured by movable barriers, as on the Brooklyn-Battery Tunnel approach, Boston’s Southeast Expressway, and Dallas’s East R.C. Thornton Freeway (I-30 East). Buffer lanes may separate bus and opposing traf- fic flows in eight-lane freeways when traffic volumes permit. Illustrative transition treatments are shown in Figure 3-35. A toll plaza provides a natural transition point since speeds are low, and enforcement is relatively simple. Transitions can also be located at (1) the junction of two freeways by provid- ing special bus ramps before the points of road convergence and (2) directly from normal freeway lanes. Ample signing should be provided at transition points and along the bus lanes. Overhead lane-control signals can be placed on special locations and on freeway over-crossing structures. Buses traveling in contra flow lanes should operate with flashers and headlights on to increase visibility to oncoming traffic. When feasible, contra flow lanes can be installed without increasing the number of freeway lanes. The lanes are free from traffic interferences or violations. Their implementation Photo 3-J. Contra flow lane on approach to Lincoln Tunnel, New Jersey. (SOURCE: Texas Transportation Institute et al., 1998) Figure 3-34. Example of cross sections for a contra flow bus lane. Contra flow bus lanes are appropriate when (1) there is a high directional imbalance in peak-period traffic, (2) the off-peak direction of travel will not be adversely affected, (3) the freeway is at least six lanes wide, (4) all normal free- way entrances and exits are to the right of the through traf- fic lanes, (5) the freeway is illuminated, (6) time savings to bus passengers exceed the time losses to traffic in the oppos- ing direction, and (7) there are at least 40 buses per hour. Examples of cross sections for contra flow lanes are given in Figure 3-34. Ideally, the lanes (and buffer) should be wide

(SOURCE: Levinson et al., 1975) (1) The illustrated layouts may be modified to accommodate either the beginning or the end of the contra-flow bus lane Figure 3-35. Transition sections for contra flow freeway bus lanes. costs are relatively low, although their operating costs are higher than for other types of lanes. Bus access is limited to beginning and end points, and sta- tions cannot be provided. Because the lanes only operate in one direction in each peak period, they do not permit all-day, two-way, multi-function BRT service. Therefore, they are suitable only for peak-period commuter express trips or as queue bypasses. 3-4.8. Queue Bypass Facilities Queue bypass lanes at metered freeway entrance ramps and on approaches to toll plazas can expedite bus flow. They are highly selective adjuncts to other BRT running way options. In this context, they can be useful as part of an overall BRT system. 3-4.8.1. Metered Freeway Ramps Separate lanes (or ramps) at metered freeway ramps can enable buses to bypass queues. Ramp metering with bus bypass lanes is appropriate when (1) freeways are congested with 3-40 lane densities of 40 to 50 vehicles per mile, (2) ramps can provide adequate storage to minimize spillback onto arterial streets, and (3) parallel surface routes are available. Illustrative designs for bus bypass lanes at metered ramps are shown in Figure 3-36. Twelve-foot lanes with shoulders are desirable to provide passing of stopped buses; however, narrower lanes without shoulders may be used in restrictive situations. The bus bypass lane can be provided on either side of a metered, mixed-flow lane or as a separate bus-only ramp on the far side (downstream) of a multilane metered ramp. Single lane entrances to the main freeway lanes are desirable. Traffic signal controls should be located a sufficient dis- tance from the freeway merging areas to allow general traf- fic to accelerate before reaching the freeway lanes. Either pre-timed or traffic-responsive traffic signal controls can be used. Space for enforcement areas is desirable. 3-4.8.2. Bus-Only Ramps Special bus ramps have been an integral part of the San Francisco–Oakland Bay Bridge and Lincoln Tunnel–Port Authority Bus Terminal express bus operations. These ramps are applicable when they (1) serve facilities with high travel

3-41 (SOURCE: Levinson et al., 1975) Figure 3-37. Example of layouts for separate bus (or HOV) ramps on freeway. (SOURCE: Texas Transportation Institute et al., 1998) Figure 3-36. Bus bypass lanes from bottleneck.

demands such as a bus terminal, transfer station, major park- and-ride facility, sports complex, or civic center and (2) provide access that would otherwise be slow, circuitous, or impossible. Bus ramps can be provided by building exclusive ramps or by converting general purpose ramps to exclusive bus use. The choice will depend on balancing the costs of new ramps against the impacts of automobile-ramp closures on freeway and arterial street traffic operations. Ramp design should provide adequate space to allow passing of disabled buses. This suggests that there should be a single lane with wide shoulders or a two-lane design. 3-4.8.3. Congestion Points and Toll Plazas Special bypass facilities may be appropriate at toll plazas and points where freeways converge. Queue bypasses are incorporated into several bridge toll plazas across the United States. Examples include the George Washington Bridge in New Jersey, the Coronado Bridge in San Diego, and the San Francisco–Oakland Bay Bridge. The bypass lanes should extend upstream beyond the normal queuing distance. Exam- ples of such bypass lanes are given in Figure 3-37. Bus lanes at toll plazas could pass through the center of the toll plaza or could be located at the far right side of the plaza. 3-5. CHAPTER 3 REFERENCES A Policy on Geometric Design of Highways and Streets—2001. American Association of State Highway and Transportation Offi- cials, Washington, DC (2001). Bus Rapid Transit Options in Densely Developed Areas. Wilbur Smith and Associates, U.S. Department of Transportation (February 1975). 3-42 Design Criteria for Metro Park and Ride and Transit Center Facili- ties. Metropolitan Transportation Authority, Houston, TX (2002). Fitzpatrick, K., K. M. Hall, S. Farnsworth, and M. D. Finley. TCRP Report 65: Evaluation of Bus Bulbs. Transportation Research Board, National Research Council, Washington DC (2001). Fuhs, C. A. High-Occupancy Vehicle Facilities: A Planning, Design, and Operation Manual. Parsons Brinckerhoff Quade & Douglas, Inc., New York, NY (1990). Gardner, G. P., P. R. Cornwell, and J. Cracknell. The Perfor- mance of Busway Transit in Developing Cities. Transport and Road Research Laboratory, Drawthorne, Berkshire, United Kingdom (1991). Guide for the Design of High-Occupancy Vehicle Facilities. Amer- ican Association of State Highway and Transportation Officials, Washington, DC (2001). Levinson, H. S., C. L. Adams, and W. F. Hoey. NCHRP Report 155: Bus Use of Highways: Planning and Design Guidelines. Transportation Research Board, National Research Council, Washington DC (1975). Levinson, H., S. Zimmerman, J. Clinger, S. Rutherford, R. L. Smith, J. Cracknell, and R. Soberman. TCRP Report 90:Bus Rapid Transit, Volume 1: Case Studies in Bus Rapid Transit. Transportation Research Board of the National Academies, Washington, DC (2003). Parsons Brinckerhoff Quade & Douglas. “NCHRP Project 20-7 (Task 135): Geometric Design Guide for Transit Facilities on Highways and Streets—Phase I Interim Guide.” Transportation Research Board, National Research Council, Washington DC (2002). Richards, B. Transport in Cities. Architecture Design and Technol- ogy Press, London, United Kingdom (1990). St. Jacques, K., and H. S. Levinson. TCRP Report 26: Operational Analysis of Bus Lanes on Arterials. Transportation Research Board, National Research Council, Washington, DC (1997). Texas Transportation Institute, Parsons Brinckerhoff Quade & Douglas, and Pacific Rim Resources, Inc. NCHRP Report 414: HOV Systems Manual. Transportation Research Board, National Research Council, Washington DC (1998).

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TRB's Transit Cooperative Research Program (TCRP) Report 90: Bus Rapid Transit, Volume 2: Implementation Guidelines discusses the main components of bus rapid transit (BRT) and describes BRT concepts, planning considerations, key issues, the system development process, desirable conditions for BRT, and general planning principles. It also provides an overview of system types. Bus Rapid Transit, Volume 1: Case Studies in Bus Rapid Transit was released in July 2003.

March 29, 2008 Erratta Notice -- On page 4-11, in the top row of Figure 4-7, in the last column, the cross street green for the 80 sec cycle is incorrectly listed as 26 sec. It should be 36 sec.

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