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Guidelines for Implementing Managed Lanes (2016)

Chapter: Chapter 4 - Traffic Control Devices

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Suggested Citation:"Chapter 4 - Traffic Control Devices." National Academies of Sciences, Engineering, and Medicine. 2016. Guidelines for Implementing Managed Lanes. Washington, DC: The National Academies Press. doi: 10.17226/23660.
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Suggested Citation:"Chapter 4 - Traffic Control Devices." National Academies of Sciences, Engineering, and Medicine. 2016. Guidelines for Implementing Managed Lanes. Washington, DC: The National Academies Press. doi: 10.17226/23660.
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Suggested Citation:"Chapter 4 - Traffic Control Devices." National Academies of Sciences, Engineering, and Medicine. 2016. Guidelines for Implementing Managed Lanes. Washington, DC: The National Academies Press. doi: 10.17226/23660.
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Suggested Citation:"Chapter 4 - Traffic Control Devices." National Academies of Sciences, Engineering, and Medicine. 2016. Guidelines for Implementing Managed Lanes. Washington, DC: The National Academies Press. doi: 10.17226/23660.
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Suggested Citation:"Chapter 4 - Traffic Control Devices." National Academies of Sciences, Engineering, and Medicine. 2016. Guidelines for Implementing Managed Lanes. Washington, DC: The National Academies Press. doi: 10.17226/23660.
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Suggested Citation:"Chapter 4 - Traffic Control Devices." National Academies of Sciences, Engineering, and Medicine. 2016. Guidelines for Implementing Managed Lanes. Washington, DC: The National Academies Press. doi: 10.17226/23660.
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Suggested Citation:"Chapter 4 - Traffic Control Devices." National Academies of Sciences, Engineering, and Medicine. 2016. Guidelines for Implementing Managed Lanes. Washington, DC: The National Academies Press. doi: 10.17226/23660.
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Suggested Citation:"Chapter 4 - Traffic Control Devices." National Academies of Sciences, Engineering, and Medicine. 2016. Guidelines for Implementing Managed Lanes. Washington, DC: The National Academies Press. doi: 10.17226/23660.
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Suggested Citation:"Chapter 4 - Traffic Control Devices." National Academies of Sciences, Engineering, and Medicine. 2016. Guidelines for Implementing Managed Lanes. Washington, DC: The National Academies Press. doi: 10.17226/23660.
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Suggested Citation:"Chapter 4 - Traffic Control Devices." National Academies of Sciences, Engineering, and Medicine. 2016. Guidelines for Implementing Managed Lanes. Washington, DC: The National Academies Press. doi: 10.17226/23660.
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Suggested Citation:"Chapter 4 - Traffic Control Devices." National Academies of Sciences, Engineering, and Medicine. 2016. Guidelines for Implementing Managed Lanes. Washington, DC: The National Academies Press. doi: 10.17226/23660.
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Suggested Citation:"Chapter 4 - Traffic Control Devices." National Academies of Sciences, Engineering, and Medicine. 2016. Guidelines for Implementing Managed Lanes. Washington, DC: The National Academies Press. doi: 10.17226/23660.
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Suggested Citation:"Chapter 4 - Traffic Control Devices." National Academies of Sciences, Engineering, and Medicine. 2016. Guidelines for Implementing Managed Lanes. Washington, DC: The National Academies Press. doi: 10.17226/23660.
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Suggested Citation:"Chapter 4 - Traffic Control Devices." National Academies of Sciences, Engineering, and Medicine. 2016. Guidelines for Implementing Managed Lanes. Washington, DC: The National Academies Press. doi: 10.17226/23660.
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Suggested Citation:"Chapter 4 - Traffic Control Devices." National Academies of Sciences, Engineering, and Medicine. 2016. Guidelines for Implementing Managed Lanes. Washington, DC: The National Academies Press. doi: 10.17226/23660.
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Suggested Citation:"Chapter 4 - Traffic Control Devices." National Academies of Sciences, Engineering, and Medicine. 2016. Guidelines for Implementing Managed Lanes. Washington, DC: The National Academies Press. doi: 10.17226/23660.
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Suggested Citation:"Chapter 4 - Traffic Control Devices." National Academies of Sciences, Engineering, and Medicine. 2016. Guidelines for Implementing Managed Lanes. Washington, DC: The National Academies Press. doi: 10.17226/23660.
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Suggested Citation:"Chapter 4 - Traffic Control Devices." National Academies of Sciences, Engineering, and Medicine. 2016. Guidelines for Implementing Managed Lanes. Washington, DC: The National Academies Press. doi: 10.17226/23660.
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Suggested Citation:"Chapter 4 - Traffic Control Devices." National Academies of Sciences, Engineering, and Medicine. 2016. Guidelines for Implementing Managed Lanes. Washington, DC: The National Academies Press. doi: 10.17226/23660.
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Suggested Citation:"Chapter 4 - Traffic Control Devices." National Academies of Sciences, Engineering, and Medicine. 2016. Guidelines for Implementing Managed Lanes. Washington, DC: The National Academies Press. doi: 10.17226/23660.
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75 Traffic Control Devices Overview Traffic control devices (TCDs) are an integral part of an overall communication plan to promote user understand- ing of routing and operations of managed lanes. This chap- ter provides guidance on how to find relevant sections of the Manual on Uniform Traffic Control Devices for applica- tion to managed lanes. The chapter also discusses challenges unique to managed lanes regarding selection and placement of signs, pavement markings, and related TCDs. As man- aged lane designs and operations continue to evolve, TCD plans must depend on the general principles put forth in the MUTCD to provide good signing for both familiar and non-familiar users. Defining Traffic Control Devices The MUTCD is approved by the Federal Highway Adminis- trator as the national standard for TCDs on any street or high- way open to public travel (1). Each state then adopts the federal manual, adds state-specific supplements, or creates its own state manual patterned after the federal version. A list of state MUTCD supplements can be found on the FHWA MUTCD website (89). The federal MUTCD website also includes infor- mation on interim approvals, interpretations, and revisions. Users of the MUTCD should check the website frequently for updated information. At the time of writing this document, the 2009 MUTCD was in force with the next planned major update to be completed in 2016. The 2009 MUTCD was the first manual to address TCDs for priced managed lanes. This version also reorganized and consolidated past sections on preferential lanes including HOV and bus-only lanes. The MUTCD is referenced extensively throughout this chapter, and the 2009 edition with revisions (1) is the version from which the guidelines and standards are drawn. Relevant interim approvals and official interpretations since 2009 are also included in this chapter. Along with the MUTCD, the federal standard highway signs and markings publication, which includes detailed design infor- mation, is available. The layouts for the new signs introduced in the 2009 MUTCD are included in the 2012 supplement to the 2004 edition of Standard Highway Signs (90). Another resource that may assist with making general deci- sions on signs and markings is the Traffic Control Device Hand- book, Second Edition (91); however, the document does not contain specific information regarding managed lanes. The MUTCD defines a traffic control device as: Signs, signals, markings, and other devices used to regulate, warn, or guide traffic, placed on, over, or adjacent to a street, highway, pedestrian facility, bikeway, or private road open to public travel by authority of a public agency or official having jurisdiction. The MUTCD applies to toll roads under the jurisdiction of public agencies or mobility authorities or public–private partnerships. These facilities, including managed lanes, are considered public highways by the MUTCD. Terms for Toll Collection Methods Electronic toll collection (ETC) in the MUTCD definitions includes transponders, license plate capture systems that bill a registered user, and license plate capture systems that bill the registered vehicle owner by mail [see FHWA (1), p. 13, Defini- tion 59]. As payment systems continue to evolve, these defini- tions may change. At the time the 2009 MUTCD was being written, license plate capture systems were just entering the marketplace as acceptable forms of payment for vehicles not preregistered in the system. Because of this, the guidance on whether so-called pay-by-mail systems qualify as registered ETC accounts is not clear in the MUTCD. In the definition of ETC, pay-by-mail systems are included, but the use of the phrase “registered ETC accounts” elsewhere in the manual may cause confusion. A subsequent MUTCD interpretation request resulted in an official ruling from FHWA regarding C h a p t e r 4

76 such pay-by-mail systems (issued November 2013). This ruling indicated systems that employ license plate capture systems for non-registered users are described in Section 2F.13 of the MUTCD concerning conventional toll roads and that these provisions apply to managed lanes as well. The official ruling included a typical layout drawing for such payment systems for managed lanes (92). Terms for Channelizing Devices A wide variety of other traffic control devices, ranging from overhead lane controls to gates for reversible and contraflow lanes, can be found in practice and are found in a variety of guidance treatises including the MUTCD. Some devices may be proprietary or customized for specific operations, such as movable barrier treatments for contraflow lanes. In such cases, the devices may not be commonly found in current guidance. Pylons used to separate managed lane operations from general-purpose traffic are not specifically addressed in the MUTCD. The word “pylon” was first used in managed lane parlance in the 1970s on contraflow lanes in New York City, Marin County, and Houston. Pylon appears in the Texas Managed Lanes Handbook (4), while California uses channel- izers in its state MUTCD (75), and Florida uses express lane markers in its state handbook (72). The California MUTCD 2014 edition defines channelizers as “flexible retroreflective devices for installation within the roadway to discourage road users from crossing a line or area of the roadway. Unlike delineators, which indicate the roadway alignment, channel- izers are intended to provide additional guidance and/or restriction to traffic by supplementing pavement markings and delineation” (75). A review of the federal MUTCD reveals that the device as used with a managed lane is not specifically discussed. The term “channelizing” is a general term covering several devices (e.g., cones, tubular markers, vertical panels, drums, barri- cades, and longitudinal channelizing devices) that are used for numerous purposes. These include providing for smooth and gradual changes to vehicular traffic flow in conditions such as a reduction in the number of lanes, channelizing traffic away from an area, providing visual separation, or prohibiting lane changing. The temporary traffic control chapter in the 2009 MUTCD shows several examples of channelizing devices in Figure 6F-7 (1). The device that is similar to what is installed to separate a managed lane from a general-purpose freeway lane is labeled “tubular markers.” Note that the devices shown in MUTCD Figure 6F-7 are orange and white since that chap- ter is concerned with work zones. Orange should not be used when there is no work zone present. While these channelizing devices have been used with managed lanes for a long time, they are not described in the national MUTCD for that application, perhaps because they have not been considered a traffic control device but rather a design feature. Whether the device is a traffic control device or a design feature could affect the use and terminology. For example, is the device supplementing another traffic con- trol device such as pavement markings, or is it a stand-alone device? Ultimately, it will be up to FHWA, with input from others such as the National Committee on Uniform Traf- fic Control Devices, to develop and/or adopt a term on a national level if this managed lane device is considered to be a traffic control device. For this document, the term “pylon” will be used. Addi- tional discussion on pylons is in Chapter 3 (pylon separation). Relevant MUTCD Sections The majority of signs and markings prescribed in the MUTCD apply to managed lane facilities. The MUTCD intro- ductory chapter (2A) for signs contains many general principles, such as for sign spreading, that are applicable and particularly important for managed lanes facilities. In addition to the overall guidance, the MUTCD contains an entire chapter specific to preferential and managed lanes. The MUTCD uses the term “preferential lane” as a high-level category descriptor for any highway lane that is reserved for the exclusive use of one or more specific types of vehicles or vehicles with at least a specific number of occupants. This term first appeared in the 1976 MUTCD and at that time focused on bus and carpool lanes. The specific type of vehicle in the case of managed lanes could include vehicles with the proper toll payment transponder, those preregistered in some other way, or those willing to pay a fee assessed through license plate recognition. The category of vehicles with a specified mini- mum number of occupants refers to traditional HOVs. A preferential lane specifies a highway lane, not an entire high- way, so toll roads where all lanes are tolled at all times are excluded from this definition. MUTCD Section 2G.01 states that toll roads utilizing ETC payments are not considered preferential lanes. The MUTCD notes that preferential lanes (Section 2G.01) can be concurrent or contraflow or be on an independent roadway on a separate right-of-way, which would include elevated roadways. These lanes may operate continuously or only at certain times of day. A preferential lane can be buf- fer separated (including the use of pylons, rumble strips, or other lane-separating devices in the buffer), contiguous (separated from the adjacent general-purpose lane only by pavement markings), or barrier separated. The MUTCD uses special terminology to distinguish among the many types of preferential and managed lanes. Figure 64 diagrams the relationship among the different terms used in the manual.

77 A managed lane in the MUTCD is a type of preferential lane defined as follows: Managed Lane—a highway lane or set of lanes, or a highway facility, for which variable operational strategies such as direc- tion of travel, tolling, pricing, and/or vehicle type or occupancy requirements are implemented and managed in real-time in response to changing conditions (emphasis added). Managed lanes are typically buffer- or barrier-separated lanes parallel to the general-purpose lanes of a highway in which access is restricted to designated locations. There are also some highways on which all lanes are managed. [FHWA (1), Section 1A.13, Defi- nition 112] Managed lanes typically restrict access to designated locations only. [FHWA (1), Section 2G.01] Priced managed lanes typically use open-road tolling where vehicles travel at highway speeds and pay tolls using a tran- sponder or through license plate capture. The MUTCD pro- vides some definitions related to open-road tolling as it relates to traditional toll roads [FHWA (1), Definitions 128–130, p. 17]. The definition of electronic toll collection specifically includes both transponders and optical scanning of license plates as collection methods [FHWA (1), Definition 59, p. 13]. The following sections of the MUTCD contain informa- tion specific to managed lanes: • Chapter 2F. Toll Road Signs. This chapter includes topics related to purple background color as well as size and use of ETC pictographs. Some of the guidance on placement of regulatory and payment signs over specific lanes at toll plazas could also inform decisions about placement for managed lane approaches and payment areas. • Chapter 2G. Preferential and Managed Lane Signs. This section was based on information for HOV lanes con- tained in older versions of the MUTCD. For this reason, some users may find it confusing when applying TCDs to newly constructed managed lane facilities not converted from existing HOV lanes. This chapter addresses regula- tory, warning, and guide signs for managed lanes. Sec- tion 2G.16 contains new content specific to more modern priced managed lanes and how to adapt the HOV sign guidance to apply to priced managed lanes. • Chapter 3D. Markings for Preferential Lanes. This chap- ter addresses lane markings as well as word and symbol pavement markings. • Chapter 3E. Markings for Toll Plazas. This chapter may be useful to review for possible pavement marking applica- tions in tolling areas for managed lanes. • Chapter 3H. Channelizing Devices Used for Emphasis of Pavement Marking Patterns. This chapter includes guid- ance for size and color of channelizing devices, such as pylons, tubular markers, vertical panels, and lane separators. General Sign Design Considerations Operating agencies are allowed to use pictographs on signs to denote a particular toll payment system. A pictograph is defined as follows: Pictograph—a pictorial representation used to identify a gov- ernmental jurisdiction, an area of jurisdiction, a governmental agency, a military base or branch of service, a governmental- approved university or college, a toll payment system, or a government-approved institution. [FHWA (1), Section 1A.13, Definition 146] Pictographs shall be simple, dignified, and devoid of any advertising. [FHWA (1), p. 29] The ETC pictograph [see FHWA (1), Chapter 2A] shall be of a size that makes it a prominent feature of the sign legend Preferential Lane Priced Lane All users pay all of the time 24/7 or fixed schedule HOV Lane Bus/Truck-Only Lane No charge, 24/7 or fixed schedule Managed Lane Changes in response to current conditions Express Lane Priced managed lane; can include HOT lanes Figure 64. Relationship among different MUTCD terms.

78 as necessary for conspicuity for those road users with registered ETC accounts seeking such direction, as well as for those road users who do not have ETC accounts so that it is clear to them to avoid such direction when applicable. [FHWA (1), Section 2F.04, goes on to provide guidance on sizes for pictographs] A pictograph is different than a symbol. The term “symbol” is limited to apply to only traffic control messages, for exam- ple, the use of a curved arrow on a warning sign as opposed to the word message CURVE AHEAD. Symbols must undergo human factors testing to determine adequate levels of com- prehension, recognition, and legibility. Unique symbols not adopted by the MUTCD may not be used on traffic control devices, except through FHWA’s official experimentation process. Symbol—the approved design of a pictorial representation of a specific traffic control message for signs, pavement markings, traffic control signals, or other traffic control devices, as shown in the MUTCD. [FHWA (1), Definition 227, p. 21] The term “logo” is often used to refer to the image, color, and letters used to identify a particular toll collection system (e.g., TxTag). The word “logo” in the MUTCD is used only on specific service signs [FHWA (1), Chapter 2J], such as gas, food, and lodging. In MUTCD parlance, the TxTag logo is called a pictograph (see Figure 65). Section 2F.13, Paragraph 11 provides a standard for the use of the pictograph on guide signs: If only vehicles with registered ETC accounts are allowed to use a toll highway, the guide signs for entrances to such facilities shall incorporate the pictograph adopted by the toll facility’s ETC payment system and the regulatory message ONLY [see MUTCD Figures 2F-1 (reproduced as Figure 66 in this document), 2F-5, and 2F-6]. The use, size, and placement of the ETC pictograph shall comply with the provisions of Sections 2F.03 and 2F.04. Source: TxDOT (93), Figure 2F-1TA. Figure 65. Example of pictograph used in Texas for electronic toll collection. Figure 66. MUTCD examples of ETC account pictographs and use of purple backgrounds and underlay panels. Source: FHWA (1), Figure 2F-1.

79 The 2009 MUTCD assigned the color purple to be used on portions of signs that include information on the required ETC payment system. No sign shall ever contain a full purple background; the purple is always used as the background color for a section of the sign, or as the background color for an underlay panel to provide contrast and emphasis for ETC pictographs. The assignment rules for purple are contained in the MUTCD toll road chapter, Section 2F.03. Because the 2009 MUTCD was unclear about ETC payment systems that use license plate capture, FHWA issued an official interpreta- tion in 2013 that indicates that a purple background is not required for these systems (92). One other section that may be relevant to managed lanes concerns the use of Internet addresses and phone numbers. Many managed lane operators like to provide enrollment information on traffic signs. These are prohibited in general in Section 2A-06 and specifically addressed for application to ETC systems in MUTCD Section 2F.18. Except as provided in Paragraph 16 and except for the Carpool Information (D12-2) sign [see Section 2I.11], Internet addresses and e-mail addresses, including domain names and uniform resource locators (URL), shall not be displayed on any sign, supplemental plaque, sign panel (including logo sign panels on Specific Service signs), or changeable message sign. [emphasis added, FHWA (1), p. 29] Section 2F.18 ETC Program Information Signs Standard: 01 Except as provided in Paragraph 2, signs that inform road users of telephone numbers, Internet addresses, including domain names and uniform resource locators (URLs), or e-mail addresses for enrolling in an ETC program of a toll facility or managed lane, obtaining an ETC transponder, and/or obtaining ETC program information shall only be installed in rest areas, parking areas, or similar roadside facilities where the signs are viewed only by pedestrians or occupants of parked vehicles. Option: 02 ETC program information signs displaying telephone numbers that have no more than four characters may be installed on roadways in locations where they will not obscure the road user’s view of higher priority traffic control devices and that are removed from key decision points where the road user’s view is more appropriately focused on other traffic control devices, roadway geometry, or traffic conditions, including exit and entrance ramps, intersections, toll plazas, temporary traffic con- trol zones, and areas of limited sight distance. One last section to highlight comes in the general design of signs section and provides some flexibility in word messages that managed lane designers may want to use: State and local highway agencies may develop special word message signs in situations where roadway conditions make it necessary to provide road users with additional regulatory, warn- ing, or guidance information, such as when road users need to be notified of special regulations or warned about a situation that might not be readily apparent. Unlike colors that have not been assigned or symbols that have not been approved for signs, new word message signs may be used without the need for experi- mentation. [FHWA (1), Section 2A.06 Design of Signs, p. 29] Guide and Regulatory Signs The introduction to MUTCD Section 2G.16 is mandatory reading for anyone concerned with the design of signs for priced managed lanes. It makes a number of key points: • Preferential lanes can be easily named by the type of vehi- cle that uses them, for example, HOVs or buses. • It is difficult to establish a naming convention for the vari- ous types of managed lanes due to continuing evolution in operational strategies. • Designing sign sequences for managed lanes must consider access points and the need to repeat operational information near every access point. The MUTCD makes several distinctions concerning termi- nology and color for signs based on whether all vehicles trav- eling that road or lane are required to provide payment through ETC accounts. These standards and guidance are spread across Chapters 2F and 2G. Note that some state MUTCDs (e.g., Texas) have included additional criteria to accommodate local practice and existing regional facilities. The MUTCD has adopted the term “express lane” to apply to priced managed lanes including those that offer discounts to HOVs. The express lane term only applies to a managed lane that has pricing as one of its operational strategies. For those facilities that only use occupancy eligibility as their management strategy, signs should designate the facility as an HOV lane and use the HOV diamond symbol [see FHWA (1), Section 2G.16, Paragraph 07]. The thinking behind this dis- tinction is that the term express lane conveys that some special requirement exists such that access is limited and pricing is employed (along with occupancy restrictions on some facili- ties). It also distinguishes these lanes (where SOVs and HOVs are both allowed) from traditional HOV lanes where an SOV would be considered a violator. Since signs in the managed lane may be visible to drivers in the general-purpose lanes, it is critical to distinguish the managed lane signs by the use of a header panel. Examples of header panels can be seen in Figure 66 on the top row. Sign placement can also help distinguish the signs intended for the different users. MUTCD Section 2E.11 includes helpful guidance on the number of signs at overhead installations and discusses the idea of sign spreading. If a single sign structure supports signs for both the man- aged and general-purpose lanes, maximum lateral separation while maintaining position relative to the center of respective lanes is desirable. For median-oriented managed lanes, canti- levered signs over the managed lane located from the median

80 barrier can be used to visually separate managed lane signs from others. The best solution is to use separate sign struc- tures staggered longitudinally so that each sign sequence on the left (managed) or right (general-purpose) is perceived as a separate sequence, separated laterally and longitudinally. This type of sign structure strategy can be costly and may result in sign clutter, but if done early in the design process, proper spacing may be achieved. Appropriate structural references and standards should be consulted, such as the AASHTO Standard Specifications for Structural Supports for Highway Signs, Luminaires, and Traffic Signals, Sixth Edition (94). Sign plans should also include all necessary warning signs, such as those indicating merging traffic (W-4 series), espe- cially for traffic entering from the left. Curve speed advi- sories, advisory speeds at access points, and lane ending warnings are other examples of typical warning signs used in managed lanes. Regulatory Signs for Priced Managed Lanes MUTCD Section 2G.17 addresses regulatory signs for priced managed lanes. Earlier regulatory sign sections [FHWA (1), Sections 2G.03–2G.07] address general signing needs that apply to all types of preferential lanes. MUTCD Section 2G.17 addresses exceptions to these standards in the case of priced managed lanes. Regulatory signs must address pricing, vehicle eligibility, hours of service, and possibly enforcement. The possibility of information overload is great with regulatory signs, especially if a complicated operational strategy is in place. Design choices concerning priority of guide signs compared to regulatory signs will need to be made. This is one area where practitio- ners should consider alternative methods of communication regarding operational rules rather than try to place multiple signs dense with information near access points. With full-time priced facilities, it may be necessary to post additional signs or plaques to reinforce the message that tolls will be collected, particularly in advance of and at entrance ramps. The standards in MUTCD Chapter 2F concerning toll roads also apply to full-time priced facilities and require the posting of the word TOLL prior to the entrance before there is no opportunity to take another route [FHWA (1), Section 2F.13]. This MUTCD chapter further stipulates the addition of the ETC-only auxiliary sign, which is the agency’s pictograph along with the word ONLY [FHWA (1), Section 2F.12]. The toll message can be introduced in route sign assem- blies serving surface street access points, as shown in MUTCD Figure 2F-4, which illustrates a yellow plaque with the word TOLL in black letters above the route cardinal direction plaque. For freeway access points, a similar yellow sign indi- cating LAST EXIT BEFORE TOLL may be needed at points where a non-priced managed lane transitions to a priced managed lane [FHWA (1), Section 2F.10]. The sections con- cerning regulatory and guide signs for toll facilities [FHWA (1), Sections 2F.10–2F.12] should be consulted for additional information. Although these sections are intended for tradi- tional toll facilities, the principles they contain can be applied to priced facilities. The issue of whether or not to post NO CASH messages at access points is one that every ETC toll facility has faced. If license plate recognition tolling is implemented, however, the need for these signs may not be as great. If drivers enter the facility expecting to pay cash and later receive a video tolling bill, the billing statement can include additional educational information about regulations and obtaining a transponder. This approach could generate a few angry customers at first but would reduce the risk of driver information overload due to cluttered signs. If there are other toll facilities in the region that accept cash, the need for the NO CASH sign is greater in order to differentiate it from other facilities. Guide Signs for Priced Managed Lanes MUTCD Section 2G.18 contains information for guide signs for priced managed lanes. It includes several layout draw- ings of sign sequencing at access points to managed lanes. One example is shown in Figure 67. State DOTs and other operating agencies must adapt the guidance provided in the MUTCD for their own unique situations. WSDOT developed the typi- cal signing plan shown in Figure 68 for a new managed lane facility opening in the Seattle area in 2015. Note that some of the signs shown in the plan do not conform to MUTCD guidance regarding maximum number of lines per sign for changeable message signs. WSDOT did follow MUTCD guid- ance on providing an exit destination supplemental guide sign to indicate general-purpose lane exits served by the upcoming egress points. Note that WSDOT uses the word ACCESS on the advance signs for the general-purpose lane to the man- aged lane rather than the word ENTRANCE used in the MUTCD examples. Driver Information Overload and Driver Expectancy Violations When designing sign sequences for managed lanes, it is very easy to overload the driver. The MUTCD provides some guidance on priority of signs in Section 2G.10 and more gen- erally in Section 2A.16: The Preferential Lane signs should be designed and located to avoid overloading the road user. Based on the importance of the sign, regulatory signs should be given priority over guide signs. The order of priority of guide signs should be Advance Guide,

81 Source: FHWA (1), Figure 2G-24. Figure 67. MUTCD example of signing for the intermediate entry to, egress from, and end of access-restricted priced managed lanes.

82 Preferential Lane Entrance Direction, and finally Preferential Lane Exit. Because regulatory and warning information is more critical to the road user than guidance information, regulatory and warning signing whose location is critical should be displayed rather than guide signing in cases where conflicts occur. Community wayfind- ing and acknowledgment guide signs should have a lower prior- ity as to placement than other guide signs. Information of a less critical nature should be moved to less critical locations or omitted. [FHWA (1), Section 2A.16, Paragraph 10] Several key issues related to sign design and installation to reduce driver information overload are addressed in MUTCD Section 2D.07 with the following guidance statement: Except where otherwise provided in this Manual, guide signs should be limited to no more than three lines of destinations, which include place names, route numbers, street names, and cardinal directions. Where two or more signs are included in the same overhead display, the amount of legend should be further minimized. Where appropriate, a distance message or action information, such as an exit number, NEXT RIGHT, or direc- tional arrows, should be provided on guide signs in addition to the destinations. [FHWA (1), Section 2D.07, Paragraph 02] Research has shown that one of the main reasons drivers do not use managed lanes is that they are not sure where they go (95). This uncertainty can be addressed in a signing plan using one or more of the following techniques: • Supplemental guide signs before and along the route of the managed lane can be used to provide information about which exit to use to access major traffic generators and major roads and streets not directly served by the man- aged lanes. Source: Chuck Fuhs, WSDOT. Figure 68. Typical signing layout for I-405 managed lane in Seattle.

83 • Use of an exit destination sign well in advance of the entrance point can inform potential managed lane users in the general-purpose lanes which exits are served while also noti- fying drivers already in the managed lane of upcoming exit points. This is illustrated in Figure 69. • Interchange sequence signs that list the distance and des- tination of the next few exits can also help. An example of interchange signs can be found in MUTCD Figure 2E-31. The application guidance for these signs is found in MUTCD Section 2E.40. They are typically used in advance of and just after interchanges the entire length of a route in urban areas. If one considers an access point to or from a managed lane to be a type of interchange, then the guidance in this section is easily applied. Another way to indicate destina- tions served is through the use of NEXT EXIT X MILES plaques, as described in MUTCD Section 2E.35. • Guide signs at intermediate egress points that reference local exits served by those egress points help reinforce the access plan for the managed lane for drivers in the lane and in adja- cent general-purpose lanes [FHWA (1), Section 2G.18]. • All guide signs along the route must be consistent in their use of control cities and destination names [see FHWA (1), Section 2E.13]. Likewise, signs should be consistent in the use of numbered highways or the common name of a route (e.g., State Highway 67 vs. Beltline Rd.). The overall sign sequence must consider spacing and place- ment to avoid further driver overload. Drivers may also be confused about destinations served due to an imbalance in directions served at interchanges and access point: • A managed lane is often designed to serve only one direction of travel (e.g., toward downtown) at an interchange. Where the managed lane intersects with another major freeway, it may be the case that drivers can access the intersecting freeway in only one direction. All interchange sequence and advance guide signs must indicate the cardinal direction of routes where only partial access is provided. • Many surface street or T-ramp access points offer access in only one direction. This is particularly common near the terminus of the managed lane where a direct-access ramp may be provided for inbound traffic but outbound traffic is expected to use the exit from the general-purpose lane. This can be addressed in informational materials and with signing as space permits to indicate inbound only access. As with general freeway design and signing, any roadway geometry that violates driver expectancy poses safety issues as well as decreased capacity: • It may be the case that some access points have unexpected directions of travel or directions of turns from surface streets. For instance, in order to access a southbound man- aged lane, an access ramp may need to run north before turning around to reach the southbound travelway. In cases like this, additional confirmation signing may be needed on the ramp as it is heading north to assure drivers that they are on the correct ramp. • Connector ramps from managed lanes to major interchanges may come earlier than expected and run parallel (or as a col- lector road) for quite a distance before turning to meet an intersecting freeway. A confirmation or pull-through sign should be provided to reassure drivers that they have taken the proper ramp. • This is also true for at-grade access points requiring merg- ing and crossing several lanes of traffic to reach the down- stream general-purpose ramp. Supplemental advance guide signs may be needed to alert drivers to exit the managed lane well before their destination is visible. • Left exits violate driver expectancies. All signs for access to and from the managed lanes should follow the guidance found in the general guide sign sections of the MUTCD. These include the use of a LEFT or left exit number plaque along the top of the sign [FHWA (1), Section 2E.31]. Note that the use of a full-width LEFT EXIT plaque at the bottom of the sign is not permitted by the MUTCD. The use of pull-through signs at left exits is also recom- mended to reinforce the main travelway for local-access left-hand ramps from the managed lane [see FHWA (1), Section 2E.12]. Left-side-oriented ramps may need to be treated with skip stripes across the gore to emphasize the mainline travel path for motorists. • When a facility includes both at-grade access points and grade-separated ones, it is necessary to indicate direction of the exit. The geometric design should be analyzed for direction of access in terms of how a driver enters or exits at Source: FHWA (1), Figure 2G-19. Figure 69. MUTCD example of an exit destination sign for a managed lane.

84 each access point. If drivers entered the lane by changing lanes to the left, then a right-exit flyover ramp might vio- late their expectation of how they will exit. By listing the directions of access, the designer can highlight potential areas for confusion and provide for additional advance signing, particularly for multilane facilities. Special Considerations for Surface Street Access Points MUTCD Section 2D.37 Destination Signs provides guid- ance on how to utilize destination names on guide signs on surface streets. The principles contained in this section may apply to certain managed lanes access points. MUTCD Section 2D.44 Advance Street Name Signs con- tains helpful information about use of phrases such as NEXT RIGHT to aid wayfinding to managed lane access points from surface streets. MUTCD Section 2D.45 Signing on Conventional Roads on Approaches to Interchanges covers signing from conven- tional roads approaching interchanges. Again, these prin- ciples will apply to advance managed lane signs for access points from surface streets. The use of an entrance direction sign with directional arrows allows the driver to be in the proper lane well before the turn into the managed lane. This is especially true if the managed lane entrance point is sepa- rate from the entrance to the general-purpose lanes. Exam- ples of these types of signs applied to managed lanes can be found in MUTCD Figure 2G-18. Wherever possible, these advance signs should be placed overhead to maximize vis- ibility. Such advance entrance and trailblazer signs can use an auxiliary plaque containing the ETC pictograph [see FHWA (1), Figure 2G-18]. Drivers may change their mind about using the managed lane once they see the current toll or estimated travel time. For this reason, open-access zones or paths at each access point to provide a way for drivers to avoid entering the lane after seeing the price, time, or destination sign should be pro- vided. For surface streets, this may mean placing these signs well in advance of the entrance point and not placing them on entrance ramps where drivers have already committed to entering. Exiting to surface streets requires adequate deceleration lane length along with an Exit Advisory Speed sign (W13-2). For many T-ramps, the intersection with the surface street is signal controlled, so a Signal Ahead sign (W3-3) may be appropriate on the T-ramp. In order to reduce weaving on the stem of the T-ramp, supplemental lane assignment signs on deceleration ramps exiting the managed lane should inform drivers which lane to be in for major traffic generators prior to the intersection. Changeable Message Signs A changeable message sign (CMS) is a traffic control device that is capable of displaying one or more alternative messages and can have a blank mode when no message is displayed. CMSs cannot include advertising, animation, rapid flashing, fading, dissolving, exploding, scrolling, or other dynamic ele- ments. The MUTCD contains specific language regarding the design and operational use of CMSs (e.g., number of lines, number of characters per line, spacing, minimum character height, and width-to-height ratio) and the design of CMS messages (e.g., length and units of information). For brevity, these items are not discussed in detail herein, and the reader is referred to MUTCD Chapter 2L. The colors used for the legends and backgrounds on CMSs must comply with the common static sign colors. If a black background is used, the color used for the text on a CMS should match the background color of the static sign it is dis- playing (e.g., white for regulatory). The MUTCD acknowl- edges newer full-matrix, full-color CMSs and encourages their use. However, the messages, signs, and symbols must comply with the applicable provisions for that type of message provided in the MUTCD. The message should be designed so that it is legible during normal daytime and nighttime condi- tions from at least 800 ft and 600 ft, respectively. When the legibility distance cannot be practically achieved or environ- mental conditions reduce visibility and legibility, messages composed of fewer units of information should be used and the message should be limited to a single phase. CMSs may be used to change the speed limit for traffic or ambient conditions (see example in Figure 70) for managed Source: Beverly Kuhn. Figure 70. Changeable message sign near Seattle indicating current managed lane speed limit different from general-purpose lanes.

85 lanes and general-purpose lanes. CMSs on roadways with speed limits 55 mph or higher should be visible from 0.5 mi under both day and night conditions. CMSs are most appropriate when travel conditions change or where operational approaches are varied throughout the day, week, or in real time. A CMS may be used to supplement, substitute, or be incorporated into preferential lane regulatory signs. Figure 71 illustrates CMS messages used by WSDOT on the I-405 Express Lanes to indicate current lane occupancy requirements. These messages are incorporated into static signs to indicate current occupancy requirements or toll pricing if applicable (96). MUTCD Section 2G.03, Paragraphs 23–25, contain information about using CMSs to display variable occupancy regulatory information as well as open/closed lane status information. Back-up and Fail-Safe Modes for Changeable Message Signs When designing power and communications systems for CMSs, agencies should provide appropriate back-up and fail- safe modes. Operating procedures should specify the default occupancy and/or toll that is to be displayed on the CMS in case of power or communication failure. Providers should have a return-to-service requirement in line with the frequency at which messages typically change. Variable Pricing and Occupancy Changeable Message Signs CMSs displaying tolling information that varies by time of day and type of vehicle are described in the MUTCD [see FHWA (1), Figure 2G-21]. When locating pricing signs, the designer should consider the sufficient distance needed between the sign and the access point so as to provide drivers with ample time to make their cost–benefit decision about whether to enter the priced lane. Driver workload is high near access points due to lane changing, weaving, and speed maintenance. For this reason, pricing signs should not be placed immediately at the gore point of the access point. Pric- ing signs should be placed upstream so the driver has time to decide whether to enter and then has adequate time to com- plete the vehicle maneuvers to do so. Drivers must be able to rely on the information provided by the CMS. The designer should coordinate with the developers of the concept of oper- ations and/or business rules for facility operation to ensure that changes to the toll charged on the facility allow drivers that have seen the previous rate displayed on the CMS to be charged the rate displayed when they were observing the sign. Some agencies use a two-phase CMS to alternate travel time information with pricing or occupancy information. While this is technically allowed in the MUTCD, driver infor- mation overload is a concern with this practice if adequate sign spacing is not provided. Traveler Information CMSs can be used to provide traveler information concern- ing incidents in the managed lane, work zone activity, and other advisory information. CMSs on general-purpose lanes should be used to provide advanced information about managed lane conditions. Messages on general-purpose CMSs must be clear in indicating that the advisory condition exists in the managed lane, not the general-purpose lane. The MUTCD does not cur- rently have standards or guidance as to how to accomplish this. Table 2L-1 of the MUTCD provides guidance on the structur- ing of multiple line messages and recommends using the first line to state the nature of the incident and the second line to indicate where the incident is occurring. Applying this prin- ciple would result in listing the name of the managed lane (e.g., express lane, HOV lane) on the second line. Travel information CMSs located in the managed lane could be used to display general-purpose lane conditions prior to an egress point. These signs will be visible to general- purpose drivers, so some agencies have used the header panel from the managed lane static sign and placed it above the CMS to indicate that the sign is intended to be read by drivers in the managed lane. The MUTCD does not provide guidance on this practice. Traveler information can also include travel time informa- tion. Many drivers will base their decision on whether to use the managed lane on their perception of the travel time sav- ings. If properly instrumented, managed lane travel times can be estimated and incorporated into a traffic management cen- ter travel time and speed information system. MUTCD Figure 2G-20 illustrates a travel time information sign that compares times in the managed lane to the general-purpose lane. This type of sign should appear in a sequence that includes advance exit information signs (listing managed lane exit points) and Source: Google Earth. Figure 71. Variable occupancy messages displayed on changeable message sign over HOV lane on I-405 Express Lanes in Seattle.

86 pricing signs to further inform the driver of the costs and ben- efits of using the managed lane. Research has shown an even split in driver understanding regardless of whether the toll price sign came before or after a comparative travel time sign (95). The MUTCD prohibitions on displaying phone numbers and website addresses applies to CMSs as well as static signs. Lane-Use Control Signals Lane-use control signals are overhead signals located over a certain lane or lanes that permit, prohibit, or indicate the impending prohibition of the use of lane(s). Lane-use control signals can be used for controlling reversible lanes in addition to indicating the open or closed status of one or more freeway lanes when any of the following situations apply: • It is desired to close certain lanes at certain hours to facili- tate the merging of traffic from a ramp or other freeway. • An indication of a lane ending is needed, such as near the managed lane terminus. • A lane may be temporarily blocked by a crash, breakdown, construction, or maintenance activities, or similar tempo- rary conditions. Shoulder-use managed lanes, in particular, benefit from lane-use control signals or larger CMSs that display open and closed status using word messages. Display Figure 72 presents the lane-use control signal symbols cur- rently included in the MUTCD and their meanings. A steady downward green arrow is used to indicate a lane is open to drivers. A steady yellow X is used to alert motorists of the need to vacate the lane over which the steady yellow X is displayed. A steady red X tells motorists that the lane is closed and they should not be driving in that lane. MUTCD Section 4M.04 contains standards and guidance on lane-use control signal operation. Each lane that may be closed must have a signal face capable of displaying the downward green arrow and red X symbols. Note that all of the symbols are steady (i.e., they do not flash). Lane-use control signals must be operated continuously, except those used only for special events or other infrequent occurrences and those on non-reversible freeway lanes, which can be darkened when not in operation. Location MUTCD Section 4M.03 specifies that color of the lane- use control signals must be clearly visible for 2300 ft under normal atmospheric conditions, unless otherwise physically obstructed (e.g., horizontal or vertical alignment). If the seg- ment to be controlled is longer or physically obstructed, inter- mediate lane-use control signals must be located over each lane at frequent intervals. Motorists must be able to see at least one signal and preferably two along the roadway. Lane-use control signals must also be located as follows: • In a straight line across the roadway. • Approximately at right angles to the roadway alignment. • Approximately over the center of the lane controlled. Reversible and Contraflow Lane Traffic Control Devices Little national or practitioner guidance is specifically pro- vided for reversible and contraflow lanes because there are so few applications, and the application often needs to be cus- tomized to each setting and design. General TCD guidance is summarized in this section for features that are considered most critical to each design. Reversible Lanes Operations on reversible lanes typically function inbound in the morning and outbound in the afternoon, and as such, the facility functions in one direction or the other during most hours of the day and night. These lanes employ gates, chan- nelized access treatments, and other traffic control devices to help prevent potential wrong-way movements, which repre- sent the greatest safety need. While some customized TCD Symbol Name Meaning Steady Downward Green Arrow Permitted to drive in the lane Steady Yellow X Prepare to vacate the lane Steady Red X Not permitted to use the lane Figure 72. Summary of 2009 MUTCD lane-use control signals.

87 concepts are applied, most employ the following devices at channelized high-speed ramps with general-purpose lanes: • Railroad gate arms of varying length to block off the ramp transition to the gore point. Placement is every 50 to 60 ft and usually involves a series of 4 to 10 gates depending on the length of the ramp taper (see Figure 73). • Crash attenuation devices at the ramp gore, usually in front of a concrete barrier. • Lane control or CMS to indicate the ramp is open or closed (see Figure 74). • Breakaway gate (in open or closed position). A vehicle- arresting device is used to stop a vehicle that goes through the breakaway gate. The screen is often automated and low- ered into position only when the ramp is closed. A typical installation is shown in Figure 75. • Similar series of railroad-type gate arms inside the revers- ible lane to channelize managed lane traffic away from the closed gate and out the other side. Fewer of these vehicle-arresting devices are employed at low-speed intermediate-access ramps from a surface street or transit support facility. The minimum device complement at these locations may include advance CMS signing, lane con- trol or CMS lane status at the entrance, and a gate that is closed. Traffic cones are sometimes used in advance of the gate to reinforce status. Figure 76 shows the reversible lane entrance/exit on I-35E in Dallas. Most projects are at least semi-automated, allowing the transition from one direction to the other to be accomplished remotely from a traffic operation center or off-site location. Confirmation of proper transition of gate closures and changes in traffic control devices using live video feeds can be useful, and almost all projects employ some modest on-site presence to verify there are no stalled vehicles in the facility prior to opening and TCDs are properly engaged for the requisite operation period. Optional traffic control devices along a reversible lane may include lane controls to reinforce the direction of travel and post information about operational status of downstream exits. Source: Chuck Fuhs. Figure 73. Transitional gate arms. Source: Chuck Fuhs. Figure 75. Tower vehicle-arresting device in place when the managed lane is closed. Figure 74. Lane control at reversible lane entrance. Source: FHWA (1), Figure 2G-1.

88 Contraflow Lanes As noted in the glossary, contraflow lanes borrow an off- peak direction lane on a controlled-access roadway and oper- ate it in the peak direction during high-demand periods typically coinciding with the morning and afternoon peak hours. Contraflow lanes require a full complement of on- site operational staffing to safely separate the lane, usually employing either a movable barrier or pylons placed into pre- drilled holes in the pavement. Either approach means that the level of automation and sophistication associated with placement of traffic control devices needs to first and fore- most protect motorists and deployment personnel. Therefore, setup procedures when closing the lane must travel with the flow of traffic, protecting deployment personnel from their rear and reversing when traffic control devices are removed. Figure 77 shows a typical deployment for a movable barrier, and Figure 78 illustrates a typical deployment for pylons. The most important aspect of contraflow design from a TCD standpoint is the crossovers that allow traffic to enter and exit the borrowed lane on each end (see example in Fig- ure 79). Crossovers involve various forms of gating, movable barrier alignments, advance signing, and often supplemen- tary traffic cones to channelize traffic into or away from the crossover, depending on the operating condition. All forms need to consider breakaway design features in case they are struck by a motorist. The crossover needs to include the same advance signing found for any other type of managed lane, plus the posted lane status through CMS elements in the sign. Pavement Markings MUTCD Chapter 3D provides information on markings for preferential lanes. Several considerations address man- aged lane pavement markings and may not be evident on reading the referenced sections. Since managed lanes, by their very operational nature, create a speed differential between themselves and adjacent lanes, separation markings need extraordinary attention. Markings installed need to be bold Source: TTI. Figure 76. Reversible lane entrance/exit on I-35E in Dallas. Source: Chuck Fuhs. Figure 77. Deployment of contraflow lanes by movable barrier. Source: Chuck Fuhs. Figure 78. Deployment of contraflow lanes by pylons.

89 and may need to consider strategies such as rumble treat- ment that discourage motorists from crossing the marking if the lane is access restricted (see Figure 80 for example). MUTCD Section 3A.06 provides basic definitions of double lines, solid lines, broken lines, etc., that should be considered when designing preferential lane markings. Word and Symbol Markings Words and symbols can be powerful communication tools to reinforce to drivers that they are about to enter a managed lane and to provide confirmation en route that they remain in the lane. Pavement markings with words and symbols are considered supplementary to signs. Words and symbols may also be desirable in declaration lanes in tolling zones where vehicles separate based on occupancy while passing under a tolling gantry. MUTCD Section 3D.01 dictates the standards for color and placement of preferential lane word and symbol markings, noting that all markings shall be white and shall be positioned laterally in the center of the preferential lane. For contiguous buffer-separated lanes, an additional stan- dard calls for the lane to be marked with one or more of the following symbol or word markings for the preferential lane use specified: • HOV lane—diamond-shaped symbol. • Toll lane—word marking indicating ETC account only, such as E-Z PASS ONLY (e.g., MUTCD Section 3D.01). • Bus-only lane—word marking BUS ONLY. • Other type of preferential lane—word marking appropriate to the restriction. For facilities that use more than one operational strategy, the symbol or word marking for each use shall be installed. This means that for managed lanes that function as HOV lanes and toll lanes, both the HOV diamond and the ETC account word (e.g., E-Z PASS ONLY) should appear in the lane in sequence. MUTCD Section 3D.01 provides guidance and support statements regarding the spacing of the markings, recom- mending engineering judgment that considers the prevailing speed and other factors such as sight distance. It also advises that preferential lane markings should be placed at strategic locations such as major decision points and should be visible to approaching traffic from all applicable lanes. MUTCD Chapter 3E contains information about mark- ings at toll plazas that may also be considered when marking tolling zones within managed lanes. Separation from Main Lanes Longitudinal markings serve two purposes for managed lane facilities: to indicate when ingress and egress are allowed and to provide demarcation of the travel lane. Regardless of whether the managed lane is separated from the general- purpose lane by barrier or buffer, pavement markings are a key component of the TCD plan. Reversible facilities have unique pavement marking needs because the typical application of yellow markings on the Source: Chuck Fuhs. Figure 79. Typical median crossover on a contraflow lane on I-30 in Dallas. Source: Chris Swenson. Figure 80. Double white wide lane lines separating managed lanes and general-purpose lanes on I-285 near Atlanta.

90 left to indicate opposing traffic depends on the direction of travel. MUTCD Figure 3D-1 is reproduced here as Figure 81 and illustrates the basic lane line color applications for revers- ible and non-reversible facilities. Separation for concurrent lane treatments takes the form of either a single wider-than-typical pavement marking or a delineated buffer employing typically two parallel markings. The width of the buffer varies, and some are much wider and incorporate pylons or other channelizers to separate traffic flows. Buffers may include gore markings (Figure 82A), but this treatment can be more complicated to maintain. Main- taining marking presence also deserves more attention than typical in order to define the space for the faster-moving lanes. For buffer-separated preferential lanes located on the left- hand side, a normal solid yellow lane is on the left-hand edge, while one of the following is on the right-hand edge: • Where crossing of the buffer is prohibited: a wide solid double white line along both edges of the buffer space (see Figure 82A). • Where crossing the buffer is allowed but discouraged: a wide solid single white line along both edges of the buffer space (see Figure 82B). WSDOT implemented the single white line on SR-167 to allow continuous access to the managed lane, after initially operating the lane with designated access points. An image used in the public information concerning the change is shown in Figure 83. • Where crossing the buffer space is permitted, such as at ingress/egress areas: a wide broken single white line along both edges of the buffer space, or a wide broken white lane line within the buffer space (see Figure 82C). The prohibited and discouraged movements shown in Sec- tion C of Figure 82 (which is an exact reproduction of Fig- ure 3D-2 from the MUTCD) conflict with an earlier section of the MUTCD. In MUTCD Section 3B.04, there is a standard that states the following: “Where crossing the lane line mark- ings is prohibited, the lane line markings shall consist of a solid double white line.” This inconsistency should be cor- rected in future editions of the MUTCD. The 2009 MUTCD also provides guidance regarding right- hand-side, buffer-separated preferential lanes and contiguous preferential lanes, which are typically found on surface streets for bus or taxi lanes. Access Points The MUTCD does not discuss pavement markings for an access point specifically beyond indicating a broken line where lane changes are permitted. In typical layout drawings in the guide signing sections, the MUTCD does provide examples of pavement markings. For example, MUTCD Figure 2G-9 provides an example of signing for an intermediate entry to a barrier- or buffer-separated HOV lane. Within this graphic is an illustration of gore pavement markings for lane channelization. ETC Areas on a Managed Lane At tolling zones, pavement markings typically do not vary if the toll reader and cameras are mounted overhead and all users are required to have ETC accounts. If a facility utilizes declara- tion areas near electronic tolling gantries where drivers are seg- regated by vehicle type (e.g., HOV vs. SOV), appropriate word markings may be used as described previously. In addition, solid double white lines that separate different managed lane user types may channelize movements into the various lanes and prohibit lane changes on approach to the tolling zone. Lane markings may delineate buffers with the use of pylons or other channelizing devices to enhance lane placement to improve toll and camera reads for some electronic tolling sys- tems (see Figure 84). Source: FHWA (1), Figure 3D-1. Figure 81. MUTCD markings for barrier-separated preferential lanes.

91 Managed Lane Bypasses at a Toll Plaza Managed lanes are sometimes applied as peak-hour bypasses at toll plazas commonly leading to bridges or tunnels. Lanes approaching a toll plaza may be operated as HOV- or bus-only lanes or may be open to other vehicles with certain registered ETC accounts. When such a lane is provided, word markings and longitudinal markings are to be used on the approach to the point where the lanes diverge [FHWA (1), Section 3E.01]. These white lane markings may be supplemented by purple markings if the conditions for the use of purple apply. The bypass is to be accompanied by appropriate channelizing devices that are discussed in MUTCD Section 3H.01 (see Figure 85). This separation should begin on the approach to the mainline toll plaza at approximately the point where the vehicle speeds in the adjacent cash lanes drop below 30 mph during off-peak periods and should extend down- stream beyond the toll plaza approximately to the point Source: FHWA (1), Figure 3D-2. Figure 82. MUTCD markings for buffer-separated preferential lanes.

92 where the vehicles departing the toll plaza in the adjacent cash lanes have accelerated to 30 mph. Other Methods of Disseminating Information Traffic control devices should not be the only method of explaining operations, routing, and payment to drivers. Other information sources such as media coverage, websites, advertising, and bill inserts should be used to explain these operations in detail. Some projects such as I-85 in Atlanta and I-10 and I-110 in Los Angeles have provided driving simulation videos via their websites to encourage potential customers to become familiar with the benefits and the look and feel of the facility beforehand, during the first months of operation, and thereafter for new customers. Minnesota DOT did an exemplary job of working with local media and community groups to educate the public leading up to the opening of its managed lanes (99). The local newspaper ran a series of short educational pieces in its transportation col- umn in the months leading up to the opening. Of course, there will always be out-of-town and unin- formed local drivers. Focus group research has shown that if drivers feel they do not understand or do not qualify for an unfamiliar facility, they are reluctant to enter and use it (100). Installation and Maintenance Considerations While the installation of traffic control devices will vary by degree of complexity, most are often the last features of the design to be implemented. For new construction where capac- ity is added to a roadway, the only unique installation chal- lenges relate to keeping unfamiliar motorists off the managed lanes until all traffic control devices are installed and the proj- ect is formally opened. This usually entails the employment of construction barrels, temporary barriers, or other means to prevent motorist confusion. Design of the traffic control devices needs to consider both the life-cycle needs and likeli- hood for repair and replacement. Most signing and pavement marking applications will represent a maintenance need that mirrors the roadway as a whole. However, CMS and toll- related devices, particularly the communication of business rules and pricing, may require rapid response to equipment failure, perhaps necessitating lane closure. To the extent pos- sible, redundancies should be considered to limit the need for lane closure. For example, multiple CMSs could provide the same information upstream and at an entrance. Multiple toll- ing readers within a given toll zone may protect integrity of the operation without the need for frequent maintenance closures. The installation of traffic control devices poses unique challenges, particularly if they are being augmented onto an existing managed lane operation. The most common aug- Figure 83. Public education image from WSDOT regarding change from designated access areas to continuous access on SR-167. Source: WSDOT (97). Source: Google Earth. Figure 84. Pavement markings at HOV declaration lane area on I-10 Katy Tollway in Houston, Texas. Source: Mark Burris (98). Figure 85. HOV bypass lanes at San Francisco– Oakland Bay Bridge.

93 mentation is the addition of pricing to an HOV lane. Often, such conversions involve more than merely implement- ing toll gantries and supplemental signing. Business rules may simultaneously require restriction of access, changes in hours of operation, and modifications of who is and is not charged to use the facility. These changes typically represent a wholesale reconfiguration and replacement of most traffic control devices on the prior roadway, and often the life cycle of prior devices has already been served. Updating traffic con- trol devices to current standards and retroreflectivity is an added benefit when such major operational changes occur. Implementing these changes can be challenging and subject the existing motorists to confusion. For example, a project in Miami restriped an HOV lane and shoulders to accommo- date two-directional managed lanes, and then over a week- end added pylons to physically separate the two lanes from other general-purpose lanes. Motorists the following Monday responded to this change by driving into the lanes, backing up, crossing through the pylons and generally creating such erratic movements that a rash of crashes resulted. The prior operation had allowed unimpeded access into and out of the lane; the modified operation restricted access. Inadequate public service announcements, driver education, project mar- keting, and installation procedures were blamed (101). This and similar experiences suggest a strategic roll-out of such changes is critical to acclimate motorists to the new managed lane operations. This roll-out will need to involve the sponsor- ing and operating agencies and installers working together to best preserve operation integrity and motorist safety. Trade-offs in Constrained Design Settings While the best TCD design follows guidance found in the MUTCD latest edition, many managed lane design set- tings are extremely constrained, with limited opportunities to place sign structures without encroaching on the travel- way. Some signing and pavement marking practices have been employed for these constrained settings on a project or statewide basis. Guidance for application of selected practices can be found in some state guidance treatises. Following are examples included in the Caltrans HOV Guidelines (53): • Median-mounted signs are placed higher than standard and/or tilted up to 43 degrees from center so that the sign will not protrude beyond the barrier footprint. • Frequency of repeating signs (e.g., hours of operation, restrictions for buffer crossing, or minimum occupancy definition of a carpool) is altered from desired standards. • Font size is reduced below the requisite design speed and abbreviations are applied for fixed-destination signing in order to reduce overall sign size. • The number of downstream destinations on destination signing is limited. • Warning signs are applied to the pavement in lieu of side- mount signs. • Barrier shapes are modified to protect the sign gantry or column. • Lane markings are placed closer together than desired, par- ticularly if multiple stripes delineate a designated buffer. • Pylons or other channelizing devices are placed in a desig- nated buffer area that is narrower than standard allowances. Another common challenge faced by practitioners is align- ment of pavement markings at a point-specific impediment that encroaches on the right or left of the travelway. These encroachments often consume much of the shoulder or lateral offset that promotes sight distance in an operation setting where speed differential requires good upstream visibility. The most common practice employed is to not deviate the lane marking around the impediment. Rather, the marking should maintain the alignment and line of sight within the travelway, as illustrated in Figures 86 and 87. The examples are not an endorsement to apply specific treat- ments but show that traffic control devices will not always fit the design setting, and some latitude is needed to give motorists sufficient information to safely navigate the lane, be informed of restrictions, and be able to make informed decisions. Additional Considerations Appropriate traffic control devices must be considered early in the planning and design process. Access points that are too close or too far apart, unusual ramp geometries, and lengthy collector roads can all violate driver expectations and cause Figure 86. Example of pavement markings at a roadside geometric impediment within a tangent section. Source: Chuck Fuhs.

94 erratic maneuvers that jeopardize safety and may also reduce the number of users. The application of additional traffic con- trol devices often cannot correct a fundamentally bad design. Traffic control devices must be considered alongside the development of a concept of operations as part of a broader user information system, which may include other media. The MUTCD points out that the limit to the complexity of an operational strategy may indeed be the ability to create signing plans to convey the information with adequate com- prehension and without overloading the driver with excessive amounts of information. The TCD plan for managed lanes must be considered in concert with existing (or new) static and dynamic signs and markings in the general-purpose lanes. Access treatments, lane separation, destination names, route numbers, and exit distances should be consistent across both sets of signs and preferably along a corridor or within a region. Source: Chuck Fuhs. Figure 87. Example of pavement markings at a roadside geometric impediment within a horizontal curve section.

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TRB's National Cooperative Highway Research Program (NCHRP) Report 835: Guidelines for Implementing Managed Lanes provides guidance for transportation agencies interested in designing, implementing, operating, and maintaining managed lanes. Guidance includes ways to define initial objectives, outline the necessary decision-making process, and address safety concerns, through the process of detailed design configuration and operation.

The contractor’s final report, NCHRP Web-Only Document 224: Research Supporting the Development of Guidelines for Implementing Managed Lanes, includes detailed background material, gap analysis, design elements, safety performance parameters, and additional related information that emerged through the case studies.

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