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Guidelines for Implementing Managed Lanes (2016)

Chapter: Chapter 1 - Introduction to Managed Lanes

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Suggested Citation:"Chapter 1 - Introduction to Managed Lanes." 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 1 - Introduction to Managed Lanes." 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 1 - Introduction to Managed Lanes." 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 1 - Introduction to Managed Lanes." 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 1 - Introduction to Managed Lanes." 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 1 - Introduction to Managed Lanes." 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 1 - Introduction to Managed Lanes." 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 1 - Introduction to Managed Lanes." 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 1 - Introduction to Managed Lanes." 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 1 - Introduction to Managed Lanes." 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 1 - Introduction to Managed Lanes." 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 1 - Introduction to Managed Lanes." 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 1 - Introduction to Managed Lanes." 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 1 - Introduction to Managed Lanes." 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 1 - Introduction to Managed Lanes." 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 1 - Introduction to Managed Lanes." 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 1 - Introduction to Managed Lanes." 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 1 - Introduction to Managed Lanes." 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 1 - Introduction to Managed Lanes." 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 1 - Introduction to Managed Lanes." 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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3 Introduction to Managed Lanes Overview Subject Context Managed lanes in the context of these guidelines are desig- nated (also defined as preferential) lanes and roadway facilities located on or adjacent to controlled-access urban/suburban metropolitan highways that are actively operated and man- aged to preserve operational performance over comparable general traffic lanes. Operational performance implies more optimal travel speeds and reliability than would be observed on adjacent general-purpose lanes that are not subject to the same level of active management. Various operational strat- egies are applied to preserve these benefits in response to specific goals and objectives. Most managed lanes serve long- distance mobility needs and are often the leftmost lanes next to the median barrier. These lanes are typically located within a public right-of-way defined as a freeway corridor. They may include provisions to address needs of specific users, such as transit stations for express bus transit. They may be adjacent to other lanes and/or physically separated. Definitions of Managed Lanes While the application of managed lanes dates back almost 50 years and covers early busway, bus lane, and high-occupancy vehicle (HOV) lane treatments, the term “managed lanes” was not commonly applied until the late 1990s. While technical and operational practitioners apply the expression “managed lanes” to a wide variety of dedicated or preferential lane treat- ments found on urban freeways and arterials, the public may be exposed to a wider range of terms based on how the projects are marketed and implemented locally. Some consistency of use is also found in terms that the Manual on Uniform Traffic Control Devices (MUTCD) gives to managed lane signing (1). In the MUTCD, managed lanes serving carpools and buses are termed “HOV lanes,” while priced managed lanes are termed “express lanes” because they often serve long-distance trips and have more restricted access than other freeway lanes. Within each locale or state, locally recognized names may be applied, such as “diamond lanes” in Texas or “carpool lanes” in California. These legacy names now recognized by generations of motorists do not necessarily need to be consistent with terms that technical practitioners apply to define a particular type of facility or operation. Within the transportation practitioner community, vari- ous definitions are ascribed to managed lanes for general and specific design and operational applications. Some terms are applied specifically by the technical practitioner commu- nity at a national level (i.e., practitioners who are planning, implementing, and operating managed lanes). Other terms are sometimes applied by practitioners within a designated region and are locally familiar. Still other terms are locally or regionally applied to aid in branding for public understand- ing and customer marketing. Thus, similar managed lanes are labeled by different names based on the practitioner and customer understandings and preferences. Each perspective is highlighted in the following sections. Overall Concept Definitions The 2013 Federal Highway Administration (FHWA) Priced Managed Lane Guide (2) provides perhaps the most succinct definition for managed lanes: Managed lanes are designated lanes or roadways within highway rights-of-way where the flow of traffic is managed by restricting vehicle eligibility, limiting facility access, or and in some cases collecting variably priced tolls. Managed lanes over the first 30 years were typically termed “bus” or “HOV” lanes; they reserve lanes for bus, vanpool, and carpool use during periods of greatest demand. By offering reserved lanes for multi-person vehicles, HOV lanes emphasize person movement rather than traditional vehicle movement, C h a p t e r 1

4thus improving the roadway’s ability to move more people in fewer vehicles. The following definition for HOV lanes is from NCHRP Report 414: HOV Systems Manual (3): A lane(s) or roadway dedicated to the exclusive use of specific high-occupancy vehicles, including buses, carpools, vanpools or a combination thereof, for at least a portion of the day. Borrowing from referenced sources that follow, and based on prior references and prior definitions adopted by the Transportation Research Board (TRB) Committee on Man- aged Lanes, the research team offers the following definition of managed lanes for this guide: Managed lanes are dedicated lanes or roadways implemented in congested freeway corridors that are actively controlled through a variety of strategies to limit flow rates and thereby preserve an acceptable level of service. By taking such measures, managed lanes generate significant travel benefits, including time sav- ings and improved reliability and operational efficiency to the roadway system. Such lanes can be added either along with new roadway facilities or as modifications to existing facilities; they should not typically be converted from existing general-purpose lanes. Managed lanes can be considered for specific bottlenecks, as corridor treatments, or as networks or systems in a metro- politan region. FHWA (2): defines managed lanes as highway facilities or a set of lanes in which operational strategies are implemented and managed (in real time) in response to changing conditions. Managed lanes are distinguished from other traditional forms of lane man- agement strategies in that they are proactively implemented, managed, and may involve using more than one operational strategy. States may apply their own definitions. For example, the Texas Department of Transportation (TxPUBLIC–PRIVATE) has developed the following definition for managed lanes (4): A managed lane facility increases freeway efficiency by pack- aging various operational and design actions. Lane manage- ment operations may be adjusted at any time to better match regional goals. As specific managed lane projects in Texas undergo plan- ning and development, this definition is tailored to address specific project needs. For example, the following variation was developed for the I-635 Lyndon B. Johnson (LBJ) Free- way managed lane project in Dallas (4): Managed lanes increase freeway efficiency by offering a pre- dictable trip with little congestion for commuters to carpool, ride bus transit, ride a motorcycle, or drive alone for those willing to pay a toll. Lane management operations and pricing structures may be adjusted at any time to better serve modal needs. The preceding Texas project definition specifically addresses priority user groups and the use of variable pricing to achieve objectives for the project. The Washington State Department of Transportation (WSDOT) developed the following definition of managed lanes in 2010 (5): Managed lane facilities include any roadway lane that can be managed to prevent congestion from occurring. In managed lanes, one or more of these techniques is used to control the number of vehicles using the lane or roadway: •  Limiting access—providing infrequent on-ramps, as on the I-5 and I-90 express lanes. •  User eligibility requirements—such as HOV only, truck only, permit only, etc. •  Pricing—tolls can be varied by time of day to control traffic volumes. By considering different forms of traffic management, it is possible to utilize the best combination of tools to keep a roadway from becoming congested over time and to optimize traffic to achieve the best person and vehicle throughput. A common element in the definitions is a broad range of potential strategies and user groups. An emphasis is made on achieving a preferential operating condition within the managed lanes, either explicitly stated within the definitions (freeway efficiency, reduction in congestion and optimized throughput) or through implicit qualities such as travel time savings, travel time reliability, free-flow speeds, or higher speeds than adjacent lanes. Definitions for Facility Types From a practitioner’s perspective, HOV lanes have histori- cally been the most widely applied form of managed lanes fitting the previously described definitions. However, HOV lanes are only one of many dedicated lane applications that currently exist or are proposed. The facility types listed in Table 1 could be considered managed lanes if they employ an operational strategy that preserves an enhanced travel con- dition. As described later in this chapter, the most common operational strategies include restricting vehicle eligibility, access control, or variable pricing through electronic toll collection. As noted, more than one term may describe the same gen- eral concept. For example, depending on who is tolled or who is given free use, the terms “high-occupancy toll (HOT) lane,” “express lane,” and “express toll lane” may all describe the same general operation. More complete definitions for each type of managed lane are found in the glossary. Table 1 contains the adopted terms and definitions used within this guide and are terms consistently applied in many prior national guidance documents sponsored by NCHRP (3),

5 the American Association of State Highway and Transporta- tion Officials (AASHTO) (6), the Institute of Transportation Engineers (ITE) (7), and FHWA (2). To give some framework to these different facility types and the management strategies that most influence what they are called, Figure 1 was generated. Historically, the strategies relied upon limited access, borrowed from early interstate express lanes that were constructed in such cities as Seattle (I-5 north) and Chicago (I-90 Dan Ryan and Kennedy), and restricted use by eligibility, which included widespread application of bus and HOV lanes nationwide. As elec- tronic toll collection technology emerged in the mid-1990s and was adopted among a wide range of tolled facilities, it offered improved lane management and led to the creation of HOT lanes where HOVs were given preferential pricing treatment. Active traffic and demand management is a fourth tool that offers various ways to dynamically manage traffic under changing conditions [see FHWA, Office of Operations (8)]. The latest applications of pricing strategies are leading to more extensive use of access, eligibility, and related active traffic management strategies on both corridor projects and regional systems that are currently being implemented. As these tools are enhanced and new technologies that influence these management strategies emerge, greater opportunities Type of Facility Brief Definition High-occupancy vehicle lane Managed lane restricted primarily to high-occupancy vehicles (no tolling applied) High-occupancy toll lane (also referred to as value-priced lanes) HOV lane that is electronically tolled for single- or lower- occupancy vehicles and free to higher-occupancy vehicles Truck lane/roadway Dedicated lane(s) for trucks Bus lane, busway, or transitway Managed lane dedicated primarily for buses Express lane Managed lane that restricts access or, according to the MUTCD definition, a managed lane that employs electronic tolling in a freeway right-of-way with or without access restrictions Toll lane (or road) Any lane/road that employs manual or electronic tolling (may not be a managed lane if travel benefits are not assured) Express toll lane(s) Managed lane employing electronic tolling that charges users a toll except those exempted Table 1. Brief definitions for various managed lanes. Figure 1. Managed lane facility types and management strategies. Source: Adapted from Collier and Goodin (9), Figure 1. This material is based upon work by the Federal Highway Administration. Any opinions, findings, conclusions, or recommendations, and translations thereof, expressed in the FHWA publication are those of that publication’s author(s) and do not necessarily reflect the views of FHWA. Incorporates all management strategies - - M an ag em en t S tra te gy Managed Lane Facility Types

6may be created to expand the range of managed lane facility types and applications. Locally Recognized Terms Some local and state agencies have used other terms from time to time to substitute for the generally recognized types of facilities described previously. Many examples where pub- lic branding is used to substitute for a specific term can be found. Table 2 lists several of these examples found in various guidance documents and published reports. Select components of managed lanes also have variations in the terms used to describe them. For the device used as a separation treatment installed in a buffer section between a managed lane and a general-purpose lane, terms that have been used include (in alphabetical order) the following: chan- nelizer, channelizing device, delineator, express lane marker, flexible delineator, lane separator, plastic delineator, plastic pole, plastic pylon, plastic traffic channelizer, plastic wall, pole, pylon, tubular marker, vertical channelizing device, and vertical panel. Another example of a feature that has different names is the device that electronically collects tolls. Trans- ponder is the most common term; however, toll tag, tag, and pass are also used in different regions of the country. Even HOV lanes have been known by different names (e.g., car- pool lanes or diamond lanes). For this document, the terms pylon, transponder, and HOV lane will be used, respectively. Managed Lanes Within the Broader Context of Transportation Demand and Congestion Management Managed lanes attempt to meter through eligibility, or in more recent examples involving pricing, actively man- age lane capacity in order to promote a preferential level of service, and thus they can be and often are complementary to many other transportation demand management (TDM) strategies commonly applied for congested metropolitan areas. Some of these measures, including rideshare promotion, preferential parking, or parking pricing programs, have related benefits when implemented in conjunction with managed lanes. These and many other strategies are referenced in TCRP Report 95: Traveler Response to Transportation System Changes (10, 11). Managed lanes are also applied as part of corridor conges- tion management programs, which typically involve a com- bination of strategies to address recurring and non-recurring congestion (i.e., crashes, weather, and special event incidents). These strategies are aimed at addressing overall management of traffic conditions and include both typical and emerging examples such as improved traffic surveillance and incident management, freeway service patrols, ramp metering, vari- able speed control, and a wide variety of advanced operational approaches. These and many other strategies are highlighted in the 2011 edition of the Freeway Management and Operations Handbook (12). Locale/Project Common Term Regional Term (Technical) Branding Term (Public Use) California, all HOV lanes HOV lane Carpool lane (1988– 2012) Carpool lane prior to 2012 California, Los Angeles (until 2013), I-10 HOV lane El Monte Busway El Monte Busway California, Orange County, SR-91 HOT lanes Express lanes, HOT lanes 91 Express Colorado, Denver, I-25 HOT lanes Express lanes Express toll lanes Florida, Ft. Lauderdale, I-595 Express toll lanes Express lanes 595 Express Florida, Miami, I-95 HOT lanes Express lanes 95 Express Georgia, Atlanta, I-75, I-575, I-85 HOT lanes Express lanes Peach Pass Lanes Massachusetts, Boston, I-93 HOV lane HOV lane Zipper lane Minnesota, Minneapolis, I-394, I-35W HOT lanes MnPass lanes MnPass lanes, diamond lanes New Jersey, SR-495 Bus lane XBL (exclusive bus lane) XBL Texas, Dallas, I-635 Express toll lanes Express lanes LBJ TEXpress Texas, Ft. Worth, SH-183/ I-820 Express toll lanes Express lanes North Tarrant Express, TEXpress Texas, Houston, I-10 HOT lanes HOT lanes Katy Tollway Utah, Salt Lake City, I-15 HOT lanes Express lanes Express lanes Washington, Seattle, SR-167 HOT lane HOT lane Good-to-Go, HOT lane Table 2. Examples of different terms used for the same facility.

7 Attributes Critical to the Success of Managed Lanes There are implicit conditions that should exist for managed lanes to be considered viable. These include the following: •  Recurring congestion (level of service [LOS] D or worse, or average travel speeds below 30–35 mph) within a corridor or region for a significant period of time. •  Significant backlog of unmet travel demand. •  Lack of available resources (right-of-way, funding, envi- ronmental, and public support) to address capacity needs in a more conventional manner that involves adding general- purpose road or fixed-guideway transit capacity. •  Interest and ability to minimally increase or alter existing roadways by managing their use for specific dedicated pur- poses to ensure that a high level of service can be provided as an alternative to recurring congestion. •  Consideration of managed lanes within the overall frame- work of congestion management and TDM strategies (i.e., managed lanes are not a stand-alone solution). Legacy of Managed Lanes The need to consider managed lanes occurred in parallel with the growth of demand on America’s newly created sys- tem of interstate highways that were being extended into and through major urban areas in the 1960s. Many treatises have documented the prevalence of recurring urban traffic conges- tion that soon followed. While some corridors were designed flexibly enough to allow for conventional roadway widening to meet added growth in demand, some early planning efforts were undertaken to make initial freeway corridors better suited to serving bus rapid transit. These efforts aimed to make urban freeways more capable of meeting future growth by serving person movement as a higher priority than vehicle movement. Notable corridors advancing this concept included the I-95/I-395 corridor (Shirley Highway) in suburban North- ern Virginia (near Washington, DC; see Figure 2) and I-10 (San Bernardino Freeway) in Los Angeles (see Figure 3). Both projects involved reconstruction of the roadways to create dedicated lanes for express buses. Some of the earli- est guidance issued to help practitioners included NCHRP Report 143: Bus Use of Highways: State of the Art in 1973 (13) and NCHRP Report 155: Bus Use of Highways: Planning and Design Guidelines in 1975 (14). This guidance included many design attributes still being applied today for in-line transit facilities and direct-access treatments. Simultaneously, corridors suffering from recurring con- gestion that included high volumes of bus commuters began to receive attention. The country’s largest patronized bus cor- ridor, SR-495 approaching the Lincoln Tunnel in northern New Jersey, suffered from daily morning commute delays averaging more than 20 min for over 35,000 commuters (13). The westbound side of the facility was converted as a contra- flow lane and opened as an eastbound-only bus lane on December 18, 1970. Figure 4 shows a photo of the contraflow bus lane in operation. The exclusive bus lane was one of several U.S. Department of Transportation (U.S. DOT) urban corridor demonstration projects to test new ways of moving people on dedicated lanes. This 2.5-mi-long project continues to serve over 35,000 com- muters daily. Other similar demonstrations for express bus transit on dedicated lanes followed in Boston, Miami, Seattle, and Houston through the 1970s. The I-10 Los Angeles El Monte busway opened in 1975 at the same time as the I-95/I-395 Shirley Highway reversible lanes. Both projects were subse- quently opened to carpools carrying three or more (3+) or four or more (4+) occupants per vehicle, respectively. Figure 2. Managed lanes on I-395 in 1980, Virginia. Source: Chuck Fuhs. Figure 3. Managed lane on I-10 in 1980, Los Angeles. Source: Chuck Fuhs.

8The Federal Role Federal policy and funding legislation have played an impor- tant role in the managed lane evolution up through the most recent priced managed lane projects that have opened. Selected events that appear to have the most significant impact on this evolution include the following: •  Federal Clean Air Act, as amended, that set the stage for air quality monitoring, mitigation plans for areas meeting non- attainment, and use of Congestion Mitigation and Air Quality (CMAQ) funds by state departments of transportation (DOTs) to implement HOV lanes as a mitigation measure. •  Federal policies that encouraged consideration of bus and HOV lanes as a congestion management measure for cor- ridors facing mobility challenges. Rules governing the expenditure of federal funds were relaxed in stages, and, by 1987, FHWA Division policies were allowing state DOTs to determine operation rules governing HOV lanes, including allowance for lowering minimum occupancy requirements to HOVs with two or more (2+) occupants. In the 1990s, federal legislation provided for motorcycle and inherent low- emission vehicle use of HOV lanes. Coupled with federal policies, states began to adopt policies supporting the consid- eration of HOV lanes. Early states to adopt such policies were California, Minnesota, Florida, Virginia, and Washington. •  Federal legislation in the 1990s encouraged improved multi- modal planning through corridor major investment studies. These studies in a number of locales often found that man- aged lanes were a particularly cost-effective strategy to pre- serve future travel demand in lieu of conventional roadway widening. •  Federal legislation over the past 15 years allowed pilot pro- grams to test variable pricing in a variety of freeway loca- tions. This program was expanded to include subsequent solicitations and grants for urban partnership agreements (UPAs) and congestion reduction demonstrations (CRDs). Project demonstrations from the 1970s through UPAs and CRDs issued in the mid-2000s have offered the most visible and recurring examples where the state of the art has been noticeably moved forward and subsequently adopted as the latest evolution in lane management practice. Such practices include variable tolling in many forms, tolling and signing for multiple access zones, provisions for active traffic manage- ment, innovative use of marketing and social media, switch- able transponders, bus transit enhancements, credit provisions for disadvantaged populations, and automated enforcement. Growth of Managed Lane Projects In 1970, only three HOV projects were operating on free- ways. Today, there are over 200 managed lane facilities. Cali- fornia leads the nation in managed lane mileage with about 36% of the national total. California was also the first state to introduce variable pricing on managed lanes. In the mid- 1990s, SR-91 in Orange County became the first managed lane to be constructed as a public–private partnership with construction and operation funded through pricing (see Fig- ure 5). I-15 in San Diego followed as the first HOV lane to be retrofitted with electronic toll collection to promote better corridor utilization in a two-lane reversible facility. These two examples generally reflect the dual practices since repeated in various other states of either constructing new managed lanes that are variably priced without carpool incentives or improving operational performance on exist- Source: Steven Yoshizumi. Figure 5. Priced managed lanes on State Route 91 in California. Figure 4. Example of exclusive bus lane in 1985, New Jersey. Source: Chuck Fuhs.

9 ing HOV lanes through variable pricing (e.g., allowing solo vehicles to pay a toll while allowing HOVs to travel free or at a discount). The vast majority of projects are concurrent lanes operated next to the median barrier as either HOV or express lanes (see Figure 6). They may operate part time or full time with a narrow buffer differentiating them from adjacent lanes. Thousands of miles of managed lanes are in operation in congested metropolitan areas (15). Figure 7 shows growth in development of managed lanes from 1970 to 2015. While the majority of projects operate as HOV lanes, since 1995 the number of projects applying tolling either as HOT or express lanes has grown. This trend is expected to continue. Practi- cally all managed lanes are added-capacity facilities, not con- verted from existing general-purpose lanes. Conversion has been tried, and except for isolated cases where no negative operational impacts resulted, the adverse traffic and politi- cal issues created were too great. This is often because a con- gested traffic lane that is converted will result in low initial levels of vehicle use, causing noticeable worsening of traffic conditions on remaining lanes and thoroughfares. Tolling a converted lane—managed lane or general-purpose lane— poses even greater challenges because citizens and drivers believe what was previously constructed and paid for with tax dollars should not be tolled. Managed lanes can provide benefits only when an assured level of service is preserved and time savings and reliability that encourage demand are realized. To provide these time and reliability benefits, managed lanes must be regulated at a flow rate that is below traditionally defined highway capac- ity. This flow rate is typically around 1600 to 1800 vehicles per hour per lane and can vary based on design and vehicle mix. When managed lanes are operated at acceptable flow rates, reliability can be assured and benefits sustained. For the subcategory of HOV lanes, moving more persons than a traditional general-purpose lane has been a benchmark for successful operation; for priced managed lanes, optimizing vehicle flow rates while preserving travel benefits has been important, particularly if project goals include generating revenue to offset implementation and operation costs. Framing the Concept: Goals and Objectives The needs and purpose commonly assessed early in corridor and regional planning studies often frame whether managed lanes are appropriate to consider in the broad mix of potential solutions. Typically, the needs and deficiencies that best charac- terize managed lane consideration include the following: •  Need for improved corridor/regional travel mobility and reli- ability, often associated with advanced traffic management. •  Need to manage travel demand growth. Source: Chuck Fuhs. Figure 6. I-405 HOV lanes in southern California. Source: Chuck Fuhs. Figure 7. Route-miles of managed lane facilities, 1970 to 2015.

10 •  Need to manage at least some roadway capacity in perpetuity. •  Need to increase access controls. •  Desire for increased person movement/vehicle throughput. •  Need for more modal choices. •  Lack of funding and need for revenue generation. •  Lack of available right-of-way and related resources to meet forecast demand. •  Inadequate transit service coupled with potential markets and supportive land uses. •  Need to support throughput for longer-distance travel. Purpose Goals for the implementation of managed lanes can vary by corridor and regional context. The following performance goals that help determine conceptual feasibility for both concept designs and operations are commonly found in many planning studies (16): •  Sustain or improve mobility, particularly during periods of peak demand, by preserving options. •  Improve roadway efficiency, safety, and reliability. •  Improve air quality. •  Promote bus transit and ridesharing. •  Improve operational safety. •  Provide travel options to meet user needs, such as time- sensitive travel. •  Generate revenue. Common themes echoed in such studies include trying to obtain more performance out of the existing roadway pavement or public right-of-way; making improvements that generate more benefit for less cost; developing projects that can stand on their own merit (i.e., physically, operationally, and financially); and examining technologies, solutions, and delivery approaches that help manage traffic better. These themes universally rec- ognize the limitations faced in a post-Interstate-building era where the existing roadways that convey people, goods, and services into and through metropolitan areas are a precious resource and need to be treated with a high level of attention in how they are designed to promote optimized performance. These themes recognize that managing congestion (not always removing or relieving it) is often the only practical goal since the effects of increasing demand will often outpace any modest capacity that can be provided. This reality is implicit in a range of corridor management strategies that include managed lanes. Objectives The developed objectives tend to be even more corridor specific and have a threshold that specifies a metric for achievement. An example objective would be the following: “The managed lane is expected to move 50% of its total vol- ume as carpools.” Example metrics currently applied include the following: •  Increasing or optimizing person and vehicle movement capacity. •  Enhancing service to bus transit and rideshare modes. •  Fitting improvements within the existing pavement or right- of-way. •  Incentivizing the use of selected vehicles, such as motor- cycles or low-emission vehicles. •  Promoting travel time savings, reliability, or efficiency for selected travel modes. •  Promoting air quality based on modal shifting. •  Generating revenue to cover construction and/or opera- tion, maintenance, and enforcement costs. •  Improving performance efficiency or enforcement on an existing HOV lane. •  Improving the movement of commerce (goods and services). •  Supporting community land use and development goals, particularly in major areas of employment. Adoption of emerging technologies such as driverless vehicles may result in consideration of other metrics. (More details on the planning process associated with establishing goals and objectives are discussed in Chapter 2.) Managed lane implementation may be represented by improvements to existing projects or new projects. For the period from 1995 through 2015, a number of existing HOV lanes were modified to incorporate tolling, add capacity, and improve performance with anticipated short-term benefits. Objectives common with such operational changes are high- lighted by representative projects in Table 3. New projects may address broader and more long-term objectives than represented by projects in Table 3. To evaluate effectiveness, goals and objectives need to be tied to that which can be measured. Linking goals and objec- tives to outcomes can help agencies respond to the following key questions: “Is the facility working as planned, and are the initial operational goals being met?” Not all measures may be quantifiable, and some may be generated from attitudinal input such as public and customer feedback. Chapter 2 (plan- ning) and Chapter 6 (performance monitoring) offer further insights into the need to study and measure performance related to stated goals and objectives. Iterative Process Goals and objectives for a corridor improvement or man- aged lanes project should inform the design, operational strategy, and project delivery approach that is employed. Expe-

11 rience over the past 40 years suggests that reaching this deter- mination involves simultaneous attention to both design and operation needs and is iterative successively through some, and perhaps many, stages of concept screening, refinement, and project development. This process will be addressed in more detail in Chapter 2 (planning). As a backdrop to this process and based on 40 years of proj- ect experience reflected in prior guidance, an implicit set of conditions that typically exist for any form of managed lane to be considered include the following: •  Congestion. A recurring congestion problem to LOS D or worse (defined as average speeds below 30 mph) within a corridor or region during the defined peak hours each weekday. •  Limited resources. A significant backlog of unmet travel demand and lack of available resources (right-of-way, fund- ing, regional consensus, or environmental issues) to address deficiencies in a more conventional means through adding roadway or transit capacity. •  Desire to promote mobility. An interest and ability by agency stakeholders to minimally or incrementally increase roadway capacity by managing its use to specific dedicated purposes to ensure that a high level of service can be pro- vided as an alternative to recurring congestion for at least some users. The public must support this approach. Managed Lane Designs Most managed lanes are retrofitted to existing corridors. Design concepts typically applied include the following: •  Concurrent flow lane. •  Separate roadway. •  Reversible lane. •  Contraflow lane. •  Queue bypass. •  Part-time shoulder use. These terms are applied in this guide for describing specific types of managed lane designs. The order presented generally corresponds to the magnitude of application in terms of lane- miles of facilities as of 2015. Each is briefly described in the following subsections. Concurrent Flow Lane Adding a dedicated left-side-oriented concurrent lane in each direction next to the median barrier has become the Project and Location A dd C ap ac ity M an ag e A dd ed C ap ac ity V eh ic le Th ro ug hp ut R el ia bi lit y M in im iz e O n- Si te En fo rc em en t G en er at e R ev en ue Le ve ra ge P ri va te Fu nd in g Pr om ot e Tr an sit Se rv ic e Bu s R ap id Tr an sit H an dl e Sp ec ia l Ev en ts I-75/I-575 Atlanta Yes Yes Yes Yes Yes Yes Yes Yes I-75 South Atlanta Yes Yes Yes Yes Yes Yes Yes Yes I-635 LBJ Dallas Yes Yes Yes Yes Yes Yes Yes SH-183/I-820 Ft. Worth Yes Yes Yes Yes Yes Yes Yes SH-114/SH-121 DFW connector Dallas–Ft. Worth Yes Yes Yes Yes Yes Some I-35E Dallas–Denton Yes Yes Yes Yes Yes Yes I-35W Ft. Worth Yes Yes Yes Yes Yes Yes Yes SH-183 extension Dallas Yes Yes Yes Yes Yes Yes I-405 Seattle Yes Yes Yes Yes Yes Yes SR-167 southbound extension Seattle Yes Yes Yes Yes Yes I-15 San Diego Yes Yes Yes Yes Yes Yes Table 3. Examples of objectives for new construction of managed lanes.

12 most widely applied concept. The popularity of this concept is due to the symmetrical layout of urban freeways with a cen- ter barrier, center-oriented bridge columns, and sign gantry columns; the availability of median shoulders, which are often converted to travel lanes; and a direction split in travel demand that is often balanced. Concurrent flow lanes can be separated from adjacent traffic by differentiating pavement markings, a painted buffer (with or without pylons), or a concrete barrier. Illustrative layouts are shown in Figure 8 for a concrete bar- rier and in Figure 9 for a painted buffer. Specific cross sec- tions detailing layouts are provided in the design discussion (Chapter 3). The physicality of separation is influenced by the concept of operations. Figure 10 shows an example of concurrent flow lanes that were retrofitted onto a freeway. Concurrent HOV lanes are found in Atlanta, Miami, Charlotte, Phoenix, Nashville, Memphis, Seattle, Dallas, Houston, Portland (Oregon), Norfolk, and Washington, DC metro areas, and most metropolitan areas in California. Separate Roadway Managed lanes can take the form of either separate road- ways or a freeway within a freeway. They may be oriented in a wide median or outer separation area or located over or under the existing freeway alignment. Increasingly, a wide variety of design concepts are being applied to separate roadways that include two-, four-, and six-lane sections with an equal num- ber of lanes in each direction. Some are implemented as two- and three-lane reversible facilities (see the following section on reversible lanes). If located alongside the freeway general- purpose lanes, they may be separated by pavement markings, pylons (example shown in Figure 11), or concrete barriers. By their nature, separate roadways have very infrequent access and typically employ grade-separated or median flyover ramps for access to handle large volumes of traffic. Examples include I-10 in Houston, I-635/I-35E/Loop 12 in Dallas, I-35W/SH-183/ I-820 in Ft. Worth, I-95 and I-495 in Northern Virginia, I-595 near Ft. Lauderdale, I-75/I-575 in Atlanta, and SR-91 in Orange County, California. Such designs may require their own inter- changes with other managed lanes on intersecting freeways. Reversible Lane As implied, a reversible facility is one to three lanes oper- ating in one direction (typically inbound) in the morning Source: Chuck Fuhs. Figure 10. Example of concurrent flow lanes in California. Figure 9. Graphic example of concurrent flow lanes with buffer separation. Figure 8. Graphic example of concurrent flow lanes with concrete barrier separation. Source: Chuck Fuhs. Figure 11. Example of roadway separated by pylons on I-10 in Houston.

13 and the other direction in the afternoon. Permanent con- crete barriers separate these lanes to prevent oncoming traf- fic conflicts. Reversible lanes are typically located between opposing directions (examples shown in Figures 12 and 13), but some projects, such as the I-75/I-575 Northwest Corridor in Atlanta, are elevated or located in the outer roadway right-of-way in a design setting representing a separate roadway. Gates and other forms of attenuation are employed at reversible ramps to safely channelize traf- fic into and out of the reversible lanes (Figure 14). Ramps Source: Chuck Fuhs. Figure 12. Example of reversible lanes on I-395 in Virginia. Figure 13. Graphic example of reversible-flow median lane. Source: Chuck Fuhs. Figure 14. Example of entrance gate on I-5 in Seattle. Figure 15. Graphic example of contraflow lane. Source: Chuck Fuhs. Figure 16. Example of contraflow lane in Dallas. can be channelized from the left of the general-purpose lanes, or flyover ramps might be provided to/from the right side. Most reversible roadways employ a wide enough typical section to include the travel lane(s) and break- down shoulder(s). Examples include I-279 in Pittsburgh, I-395/I-95 in Northern Virginia, I-25 in Denver, I-394 in Minneapolis, I-5 and I-90 in Seattle, I-595 in Ft. Lauderdale, I-75 north and south in Atlanta, and various projects in Houston and Dallas. Contraflow Lane Where the directional split is uneven, typically with 60% or more of the peak-hour traffic traveling in the peak direc- tion, there may be an opportunity to borrow an off-peak direction lane for peak direction flow. Contraflow lanes may be separated by traffic pylons placed in the pavement (SR-495 in New Jersey), as shown in the graphical example in Figure 15. They may also be separated by movable bar- rier (I-30E in Dallas or I-93 in Boston), as exemplified in Figure 16. Either form of deployment requires a regiment of support staff to safely close off and reopen the lane to general-purpose traffic before and after each operating period.

14 Queue Bypass A short, dedicated lane may be implemented around a point- specific traffic bottleneck. This bottleneck may be operational or geometric in nature. The most common queue bypasses exist on approaches to bridges and tunnels, approaches to toll plazas, and metered entrance ramps. The bypass may be functional only for the period of time that a queue typically forms, and some queue bypasses are now tolled at a differential rate from other lanes if implemented at a toll plaza. Examples include most bridge approaches in the San Francisco Bay Area, and many ramp meters located throughout California. A photo example is shown in Figure 17, and a graphic example is shown in Figure 18. Part-Time Shoulder Use In a few locations, vehicles are allowed to travel on emer- gency breakdown shoulders (also known as part-time shoul- der use or dynamic shoulder lanes) under specific conditions. A left shoulder may be converted and posted for part-time shoulder use operation using a variety of traffic control devices, as is represented by the I-35W HOT lane project in Minneapolis (see Figure 19). Other right shoulders in Minneapolis–St. Paul are conditionally used by transit buses whenever congested speeds fall below a given threshold. A right-side shoulder was opened to general-purpose traffic on I-66 in Northern Virginia during the same hours that a left- side general-purpose lane was restricted for HOV-only use (see Figure 20). One or more facility types may be found in a given project, corridor, or regional system. There are various ways to safely transition from one facility type to another. Managed Lane Strategies Common managed lane strategies used to regulate demand fall into three broad categories: •  Vehicle/user eligibility. •  Access control. •  Variable pricing through electronic toll collection. Historically, before the mid-1990s, managed lanes applied vehicle/occupancy eligibility often in combination with access control to regulate lane demand. Figure 21 shows example facil- Source: Chuck Fuhs. Figure 17. Example of queue bypass in California. Figure 18. Graphic example of queue bypass. Source: Kay Fitzpatrick. Figure 19. Example of left shoulder used as a managed lane in Minneapolis.

15 ity regulatory signage. After the advent of electronic toll collec- tion, pricing became a demonstrated and adopted strategy that continues to gain interest and practice. While these strategies are applied in other traffic management applications and may offer unique benefits in these other settings, they have specific relevance to actively managing lane demand in this context. A wide variety of emerging projects are expanding how each strat- egy is applied. Each strategy can be applied and implemented individually or in combination, depending on the unique travel demand conditions associated with each project setting. Vehicle Eligibility The purpose of restricting vehicle eligibility in a managed lane has been primarily to encourage more person movement over solo driver vehicles on constrained corridors where lim- ited capacity is available. This purpose dovetails well into the goals of transportation demand management and requires users to switch modes (i.e., into carpools, vanpools, or transit from private solo commuting) during periods of peak demand. HOV lanes serve this purpose as a typical application. Other eligible users, notably motorcyclists and low-emission vehicles, have also been allowed as exempt from the minimum occu- pancy restriction on HOV lanes. In this context, encourag- ing rideshare formation and use of transit and low-emission vehicles can also fit well as a mitigation measure to improve a region’s air quality goal. Safety also plays a role, as segregating motorcycles into a dedicated lane from the general traffic stream can promote a safer operation. Other occupancy-exempt vehicle classes include emergency vehicles, deadheading buses, and para- transit vehicles. Eligibility restrictions can be in effect 24 hours a day or vary by time of day or day of the week. A managed lane using a variable eligibility strategy may restrict use to 3+ occupant HOVs during the peak commute hours and relax restrictions to include lower-occupancy vehicles during off periods or weekends. Experience from almost 40 years of HOV lane operation suggests that this concept has worked well and is trans- ferable into a number of operational and design settings. HOV lanes are found in at least 29 metropolitan areas in the United States and Canada, with additional implementa- tion in Australia and Europe. Some projects stretch more than 50 mi in length, while others may only serve as short queue bypasses on ramps and on approaches to bridges and tunnels. Typical experiences reflect the following overall findings: •  The typical project is usually at least 8 to 10 mi in length. •  Time savings generated average about 0.5 min per mile during peak hours. •  The vast majority of HOV lane projects are operated con- current flow (i.e., with the flow of traffic and often sepa- rated by pavement markings or a marked buffer). •  About half of all projects operate in the peak periods only, reverting to a general-purpose lane in the off-peak period; the other half operate full time. •  Most HOV projects were sponsored, implemented, and operated by the respective state DOT. HOV lanes are examples of limiting use to specific vehicle classes such as carpools based on the number of persons they are carrying. In the example in Figure 22, buses operated on reversible express lanes. Most commonly, user restrictions on HOV lanes have taken the form of eligibility requirements based on the requisite minimum number of people traveling in a vehicle. Source: Chuck Fuhs. Figure 20. Example of part-time shoulder use sign in Virginia. Source: Chuck Fuhs. Figure 21. Occupancy restrictions on HOV lanes in Santa Clara County, California.

16 Access Control Some practitioners may consider the first managed lanes to have been express lanes incorporated into controlled- access urban roadways in the late 1950s and early 1960s. Such projects as the I-70 Daniel Boone Expressway in St. Louis, I-94 Dan Ryan and Kennedy Expressways in Chicago, and I-5 express lanes in Seattle conceived designs that limited access to a few designated locations, thereby achieving a high level of service for longer-distance travelers. (Note that the term “express lane” found on signs in this early context was likened to express buses that traveled the same corridor but had limited stops, rather than the definition of express lane currently found in the MUTCD for tolled managed lanes, which applies the same terms.) Access control has been similarly applied to many man- aged lane projects since then, but always in context with other strategies. For example, the reversible lanes on the I-5N HOV lanes in Seattle, by the very nature of operating a roadway that reverses by time of day, must be barrier separated from other lanes and thus limit access to a very few designated locations. The most widespread use of access control is associated with concurrent flow managed lanes located next to the median barrier where an access restriction is more liberal, provid- ing for ingress/egress or weave movements about every 1 to 3 mi. Many projects restrict access to reduce friction caused by indiscriminate entering and exiting; to discourage shorter- distance travel, which can promote an excessive number of weaving movements; and, for tolling purposes, to make toll collection easier to manage by having fewer toll zones than might otherwise be required. Limiting access has traditionally been applied to HOV and express lanes as a means of regulating entry and exit move- ments. Restricting access by this method helps ensure that dedicated lanes do not become overloaded regardless of the level of demand they generate. Access restrictions may also help alleviate specific traffic bottlenecks where short-distance trips cause a lane to exceed its capacity. As an example, as Figure 23 illustrates, HOV access restrictions are applied on many projects in the Los Angeles area where demand is high. Access is also restricted in various multilane facilities and on reversible facilities where positive separation between opposing flow is required. Access can be restricted by design or dynamically managed by (a) metering demand at entrance ramps via the use of traffic signals or gates, (b) limiting access at specific ramps to selected users like HOVs (e.g., I-5 Seattle downtown ramps), or (c) limiting the number of entrance and exit ramps so that free-flow is ensured (e.g., I-5N in Seat- tle and I-15 in San Diego). Access control is not required for electronic tolling or variable pricing, and some projects such as SR-167 express lanes in Seattle have adopted a more open- access strategy since opening. Electronic Tolling and Variable Pricing The adoption of electronic toll collection technology has allowed variable pricing to become an increasingly practical and more precise way of regulating demand in real time. Examples of signs are shown in Figures 24 and 25. Variable pricing, where tolls vary in accordance with a fixed schedule or demand, can help maximize the use of available lane capacity while continu- Source: WSDOT. Figure 22. Express lanes on I-5 North in Seattle with bus-only ramp (in 1980). Source: Chuck Fuhs. Figure 23. Typical HOV lane access in California.

17 ing to prioritize operation for users. This type of tolling offers an opportunity to manage a preferential lane or roadway in real time as capacity allows. Tolling in general can be a crude or fine-tuned tool. If fixed tolling is applied, it simplifies the message to users but limits the ability to regulate demand. Varying tolls by a fixed schedule that rises and falls in accordance with observed demand can accomplish the desires of managing demand and assure the customer of the toll that will be charged at a selected time. Dynamically varying tolls in accordance with real-time demand is often a better solution from the opera- tor’s perspective but makes communicating the toll to users potentially harder, particularly if there are multiple toll zones involved. The primary purpose of variable pricing in most applications is to keep the lane(s) from becoming congested and assure a high degree of reliability. U.S. federal law, current as of the Fixing America’s Surface Transportation (FAST) Act of 2015, requires a 45-mph mini- mum speed threshold for managed lanes approved under Title 23 U.S. Code (U.S.C.) Section 166, including all federally funded HOV lanes and some priced managed lanes. Addi- tionally, many priced managed lanes that have been approved under 23 U.S.C. Section 129 have adopted the same mini- mum threshold as for Section 166 facilities. Taken together, most priced managed lanes in operation by 2015 maintain this 45-mph minimum speed threshold, and do so through the use of variable pricing. Higher tolls are usually charged when congestion is heaviest and delay is at its worst, while lower tolls are often posted during off-peak periods of low demand. Higher levels of tolling can encourage some peak- period users to shift their trip to lower-demand periods or shift into the managed lane with the belief that the toll reflects degraded mainlane conditions ahead. If the priced managed project allows free or discounted use to HOVs with a certain minimum number of persons, then it may be referred to as a HOT lane. In the MUTCD (1), all priced managed lane projects are referred to as express lanes on signs and may carry the locally recognized project brand and pictograph of the toll transponder program(s). In 2015 variable pricing was in use on 30 projects nation- ally, employing electronic toll transponders based on pre- established customer accounts. These projects reflected both new capacity treatments like SR-91 express lanes in Orange County and conversions of prior HOV lanes like SR-167 HOT lanes in the Puget Sound region. Traffic Management Technology A wide variety of traditional and emerging intelligent transportation system (ITS) strategies are employed on man- aged lanes. Posting travel time on changeable message signs was perhaps one of the earliest applications. More recently, active traffic management concepts are being applied on corridors such as I-5S in Seattle (see Figure 26) and I-35W in Minneapolis (see Figure 27). In both cases, active traffic management employed for the entire roadway is designed Source: Chuck Fuhs. Figure 24. Example of electronic toll collection sign in Minneapolis. Source: Kay Fitzpatrick. Figure 25. Example of electronic toll collection on a managed lane in Atlanta. Source: WSDOT. Figure 26. Dynamic speed signs in Seattle (HOV lane is leftmost with higher speed).

18 to complement the respective HOV or express lane opera- tion. Tools employed include dynamic advisory speed limits (e.g., in Minnesota; see Figure 27), dynamic regulatory speed limits (e.g., in Washington State; see Figure 26), queue warn- ings, lane controls advising of closures, and dynamic pricing information. Combining Strategies— Looking Forward Many managed lane projects employ multiple strategies. Since a high percentage of future managed lane projects will include some application of variable pricing or tolling, the practitioner can expect to see most projects continue to embrace all of these tools for the foreseeable future. In the extreme, pricing may only be employed on some HOV lanes to smooth out periods of excessive use when lane operations are degraded and infill demand when available space allows. For tolled facilities needing to meet revenue targets, free use (if any) may be limited to registered transit buses. Observed trends looking forward, based on projects being planned and in development, suggest that managed lanes will continue to expand. Managed lanes also appear to be the focus of attention for the next adopted technol- ogy, whether it be simply making enhancements to toll collection and account management or implementing auto- mated vehicle–highway strategies to improve operational performance. Tolling enhancements will likely involve easier means for customers to use toll facilities throughout the United States, based on federal legislation requiring interoperability among tolling agencies. Mobile applications that permit easier cus- tomer account management and use of tolled managed lanes through mobile devices also appear to be on the threshold of adoption. These and other means will give users more ways to use managed lanes. Automated vehicles (AVs, also referred to as “automated vehicle–highway technology” or “autonomous vehicles”) may address a wide range of markets within managed lanes. The National Highway Traffic Safety Administration issued a preliminary statement of policy concerning AVs in which different automation levels and possible contributions of automated vehicles are explained. Potential benefits of vehi- cle automation are enhanced safety, reduced fuel consump- tion, enhanced mobility for motorists with disabilities, and reduced congestion (17). In addition to the automation of vehicles, there are con- nected vehicles (CV), which are able to communicate with each other [vehicle to vehicle (V2V)] and with the roadway infrastructure [vehicle to infrastructure (V2I)]. FHWA esti- mates that V2I has the potential for advancement in safety and operations of surface transportation. This automation service will improve traveler information and service by mak- ing it possible for infrastructure and vehicles to communicate and cooperate (18). A study for the Metropolitan Transpor- tation Commission in the San Francisco–Oakland Bay Area identified nine use cases for V2I technologies on managed lanes. These uses include toll collection, dynamic pricing, in-vehicle account management, back-office toll processing, vehicle occupancy, automated enforcement, probe vehicles, traveler information, and traffic management for the region and the corridor (19). While some AV applications may be ready for demonstra- tion soon, other applications to expand throughput or to per- mit reduction of lane widths to squeeze in additional managed lane capacity may be several or perhaps many years ahead. Some practitioners believe these applications may be better suited for initial demonstrations in the segregated design environment of managed lanes before being more widely adopted. These applications have many policy implications and may be demonstrated within the next few years before more widespread adoption. The past 40 years show how many times managed lanes have evolved in embracing new strategies while preserving the overall intent of maintaining mobility to the greatest number of users. Decision-Making Process Traditional Process for New Projects Historically, the decision-making process for managed lanes follows a project development path that traditionally involved a design–bid–build–operate–maintain paradigm not unlike any other highway in an urban setting. The nuances often missed included a much greater need to focus on public and political support; marketing and outreach to customers Source: Kay Fitzpatrick. Figure 27. Dynamic speed signs in Minneapolis.

19 prior to opening; costs that were difficult to predict for long- term dedicated operation, enforcement, and maintenance; and regular performance monitoring to address changing traffic and demand conditions. Planning decisions were often the result of opportunities based on either funding or policy, or resulted from a program to rehabilitate or rebuild a corridor. Decisions were generally made within the state DOT or with transit, state police, or regional/municipal agencies that were local partners. In some areas, a transit or regional transportation agency would take the lead on an HOV or transit-oriented managed lane within the state’s right-of-way. These early partnerships proved what was possible. Many such projects were and have been legacy successes and, for the most part, transcended original agency staff that made them happen. The adoption of pricing and funding limitations have greatly expanded the decision-making process to include a wider array of potential funding, delivery, and partnership arrangements. It is noteworthy that the first public–private partnership in California involved a managed lane project in Orange County in the mid-1990s. The most creative and dynamic project to attempt to adjust to future demand— a four-lane facility in San Diego that could become a 2-2 or 3-1 configuration throughout the day—was born out of a unique local partnership between the California Department of Transportation (Caltrans) and the San Diego Association of Governments, an agency that serves as the metropolitan planning organization (MPO), transit provider, and toll oper- ator, as well as local funding implementer. The bulk of such public–public and public–private partnerships in Califor- nia, Colorado, Florida, Georgia, Texas, and Virginia similarly involve managed lanes. Traditional and newly organized state and regional trans- portation and toll authorities are playing an increasing role in partnering with state DOTs in the implementation and operation of tolled managed lanes. Each area appears to have unique partnering resources that, when taken as a whole, show funding decisions gravitating to local and state agen- cies, in concert with traditional federal participation. This decision-making process is allowing projects to be tailored to each region, and consistency of practice occurs at a regional rather than project-specific or state level. Based on past and recent experiences, the decision-making process for managed lanes needs to engage the agencies and operators who have the greatest potential for making the project successful, and they need to be involved at the out- set during the planning process. These agencies include the MPOs, implementing agencies (typically the state DOT and any regional transportation implementing agencies), transit operators, enforcement personnel, tolling providers if the facility is likely to be priced, and rideshare services if incen- tives to carpools and vanpools are envisioned. Decisions need to engage these participants actively. Inevitably, project expe- riences show that tough trade-offs are required to achieve a balance between desired operations, designs, financing, and policy considerations on how the managed lane is able to meet stated goals. The following planning (Chapter 2) and imple- mentation (Chapter 5) discussions offer further insights into how decision making occurs. Decision Making for Operational Changes The large number of managed lanes in operation—some for many decades—has led practitioners to make improve- ments to these projects to enhance performance and embrace the latest technology. While some operational changes may rise to the scope of representing new construction, most are modest changes with commensurately minor design impacts focused on near-term benefits and a short anticipated life cycle. Such changes may include addition of tolling infra- structure and changes in access or separation with adjacent lanes, signing, and other design and operational features. These changes often have minimal impact on corridor demand, particularly when examining the overall freeway. For these settings, the decision-making process should be simpler than what is currently occurring. Unfortunately, interviews with practitioners in 2015 as part of this guid- ance development indicated that decision making was being unnecessarily complicated. Some practitioners were trying to look at long-term impacts, which are frequently overshad- owed by macro-level traffic growth that the modest changes cannot affect. Some improvements can be controversial, requiring the same level of public dialogue that a full project might require. Safety Performance Managed lanes can provide safety and operational perfor- mance benefits over general-purpose facilities, but the man- aged lane strategy must be appropriate for the intended user group. Specific benefits in crash reduction seen at one facility do not necessarily translate to another facility, so the selected strategy must account for the conditions unique to a particu- lar facility. Crashes Within the Facility Crashes on managed lanes can be related to access, con- gestion, and sight distance (see Chapter 3). These factors are compounded by failure to appreciate driver expectancy that differs for managed lanes as compared to general-purpose lanes. Adequate attention to placement of traffic control devices can help (see Chapter 4). In addition to crashes near access points, crashes can also occur within a managed lane

20 facility. Common types of crashes within a facility include the following: •  Rear-end crashes due to congestion. •  Sideswipe crashes due to passing on two-lane facilities or within access zones. •  Crashes caused by drivers making unexpected maneuvers at the point where access restrictions apply or to avoid debris or disabled vehicles that may block the travelway. Crashes such as these underscore the need to have a cross section (e.g., number of lanes plus shoulder and buffer offset widths) that is sufficient to meet the needs of the expected users of the facility. A safety study for the I-394 MnPass Lanes in Minnesota (20) found the overall number of crashes to be reduced by 5.3%. A 4-year observation period was used before the start of tolling, as well as a 2-year post-deployment observation period. The economic benefit was found to be $5 million dur- ing the period of 2006 to 2008. The authors of the paper are not confident their results can be generalized to other HOT lane projects because of limited research on this issue (20). A 2013 paper (21) reported on an evaluation of the rela- tionship between cross-section design (i.e., lane width, shoul- der width, and buffer width) and safety performance for HOV lanes. The authors used 3 years (2005 through 2007) of crash data for 13 Southern California segments totaling 153 mi. The segments were buffer separated between the HOV lanes and the general-purpose lanes. Crashes included those that occurred on the median shoulder, in the HOV lane, or in the adjacent general-purpose left lane. Independent variables included geometric attributes and annual average daily traffic (AADT). The authors found that wider HOV lane width and wider shoulder width were associated with lower crash fre- quencies. For their dataset, buffer width and the width of the lane next to the HOV lane were not found to be statistically significant. The authors also provided case study examples of preferred cross-section allocation if converting a section from an HOV lane and left shoulder to a section having a buf- fer, HOV lane, and left shoulder. In all examples, the authors recommended the inclusion of a buffer by reallocating some of the shoulder width to the buffer. A Florida study (22) developed crash prediction equations for freeway facilities with HOV and HOT lanes by number of freeway lanes. Models were developed for 6-, 8-, 10-, and 12-lane freeways (number of lanes reflect both directions and include the managed lanes). For all the models, segment length and AADT were significant and included. For most of the models, left shoulder width was the only other significant variable. An increase in left shoulder width was associated with decreases in crashes. The effect of buffer type on crashes was found to be statistically significant only in the model for 10-lane freeways. The inclusion of a 2- to 3-ft buffer was asso- ciated with fewer fatal and injury crashes. The findings from the safety literature—along with guid- ance in the Highway Safety Manual (23)—are clear in that a reduction in a freeway left shoulder width is associated with an increased number of crashes. Safety studies for general- purpose freeway lanes also have found that reduction in lane width is associated with more crashes. Some of the increases in crashes due to reduction in lane or shoulder widths could be offset if the reductions are due to including an additional freeway lane (24). The evaluations of the safety benefits of buffers are lim- ited. For the two studies that included buffer-separated projects within the evaluations (21, 22), there was only one case (on 10-lane freeways) when the variable was statisti- cally significant. Limitations in sample size along with the distribution of the buffer widths available may be affecting the results. Crashes at Access Points Access points are common sites for crashes, just as crashes can commonly be found at intersections on surface streets. Crashes near access points can involve vehicles entering or leaving the managed lanes (e.g., sideswiping another vehi- cle, striking separation device, etc.), and crashes can involve vehicles that are not changing facilities (e.g., rear-end crashes caused by drivers braking to avoid a vehicle entering the facil- ity in front of them). Volume of traffic, type of access and separation provided, and proximity of managed lane access to general-purpose entrance and exit ramps may all influ- ence crashes, and these effects may vary from one facility to another. A California study (25) described comparisons of traf- fic safety during the morning and afternoon peak hours in extended stretches of eight HOV lanes with two different types of access—four corridors with continuous access and the others with limited access. Traffic collision patterns in the two different types of HOV lanes were investigated by evalu- ating (a) the differences in collision distribution, severity, and type, along with per-lane traffic utilization; (b) the spatial dis- tribution of collision concentrations by using the continuous risk profile approach; and (c) the collision rates in the vicinity of access points in HOV lanes with limited access. In their study, the researchers conducted detailed analysis on collision data occurring during peak hours in relation to geometry and traffic features. Based on the findings from the assessment on eight routes, the limited-access HOV lanes appeared to offer no safety advantages over the continuous-access HOV lanes. The finding was attributed to more frequent and sporadic distribution of collision concentration in limited-access HOV lanes. In other words, the controlled-access HOV lanes had a

21 similar frequency of crashes as the continuous-access lanes; however, the crashes were concentrated at the access points. Driver Expectancy Driver expectancy reflects the driver’s readiness to respond to situations, events, and information in predictable and suc- cessful ways (26). Providing a roadway network that conforms to a driver’s expectancy should result in a better operating and safer system. Uniformity can improve expectancy, which supports having traffic control devices in conformance with the MUTCD. Violations of driver expectancy can lead to erratic movements, which can cause crashes, and can result in decreased use of the managed lane system because drivers do not understand it. Left exits and entrances are unexpected and can cause erratic movements; however, left exits and entrances are common on managed lanes because many managed lanes use the leftmost lane of a freeway. Additional guidance on human factors concepts is available in NCHRP Report 600: Human Factors Guidelines for Road Systems (26). Addressing driver expectancy issues may include one or more of the following considerations: •  Trying to meet as many desirable design attributes as pos- sible for project retrofits. •  Ensuring more weave distance for at-grade slip ramps where the highest volumes are anticipated. •  Posting advisory speeds, flashing beacons, and diagram- matic signs on direct ramps that tee into an intersecting street that the driver cannot see in advance. •  Designing wider-than-standard shoulders in curves and areas of limited sight distance next to median barrier walls. •  Keeping drainage inlets and pavement swales in the median out of the travelway. •  Avoiding signage information overload by adopting prin- ciples beyond MUTCD guidance that prioritize driver infor- mation needs. •  Building in design provisions, such as pullouts, for on-site enforcement where full and continuous shoulders cannot be provided. •  Minimizing temporary and permanent termini conditions that do not provide sufficient downstream merge capacity. •  Providing a buffer for improved sight distance, even for part-time operations. •  Designing for most vehicles, even if the intended users are limited to specific vehicle classes. •  Providing illumination at ramp gores and enforcement areas. •  Designing for flexibility, which may include consistent depths of pavement for travelway and shoulders, at-grade access treatments that can be easily modified, and signing gantries that can accommodate potentially larger, heavier signs when rules change. •  Highlighting potential driver expectancy concerns in public outreach materials. As an example, public outreach material that highlights the need for a managed lane vehicle to exit a greater distance upstream than would be expected so that the managed lane driver is in position for the needed general- purpose lane exit could be provided. Audience and Organization of Guidance Audience This guide is written to primarily address technical practi- tioner needs in planning, evaluating, implementing, design- ing, operating, and maintaining managed lane facilities on urban freeways. The guide attempts to answer what the practi- tioner needs to know in order to confidently engage in imple- mentation of managed lane facilities, with recognition that best practices are often adopted from peer projects within the region or other locales that share similar operational or design attributes. In various chapters, the practitioner is referenced to other parallel documents and resources that are available and, in some cases, offer more depth on a particular subject than can be found in this guide. The intended audience includes practitioners primarily involved in planning, implementing, and operating managed lanes on an access-controlled facility. Practitioners include engineers, planners, environmental spe- cialists, operators, enforcement agents, and public relations professionals. The focuses of this audience of practitioners can be categorized as follows: •  Agency: federal, state, and local planning, financing, and implementing agencies; public and private perspectives (MPOs, DOTs, and state/local/regional toll and mobility agencies, transit agencies, municipalities). •  Planning: highway, bus transit, MPOs, TDM providers. •  Design: highway, bus transit, toll agency, consultants, toll system providers. •  Operations: traffic, enforcement, maintenance, tolling sys- tem providers, maintenance services. Topics Included/Organization The topics include all types of dedicated lane treatments cur- rently being applied and located on urban access-controlled (high-speed) roadways that employ various traffic and pric- ing tools to manage demand and provide travel reliability. Each topic will generally include an introductory discussion, why the topic is important, options in practice, a synthesis of practice highlighting pros and cons for different options, and references to resource documents where more detailed information can be found.

22 The guide consists of six chapters that generally frame the topic areas applied to project implementation. To properly address the close synergies between design, traffic control devices, operation, and implementation, the reader is encour- aged to explore these topic areas in tandem because each is heavily influenced by the others in the iterations required to reach consensus on a best approach for a particular project. The chapters of this guide are as follows: •  Chapter 1 provides an orientation to the managed lane con- cept and background, as well as a contextual understanding of the role managed lanes serve as one component associ- ated with corridor congestion management and TDM. •  Chapter 2 addresses the planning process and highlights unique planning issues commonly confronted in managed lane project development. •  Chapter 3 covers design elements to consider in managed lanes and related supporting transit, enforcement, access, and tolling infrastructure. •  Chapter 4 addresses the parallel design needs associated with traffic control devices used on managed lane designs. •  Chapter 5 focuses on implementation and deployment. •  Chapter 6 covers operations and maintenance. A list of commonly used abbreviations and a compre- hensive glossary of terms related to managed lane practice are included after Chapter 6. Many of these definitions are borrowed and referenced from parallel documents includ- ing NCHRP Report 414 (3), the FHWA Priced Managed Lane Guide (2), and various state DOT guidance publications. Topics Not Included The following topic areas are not included, primarily because either (a) the applications are not dedicated lanes located in a freeway setting or (b) more detailed guidance can be found in other treatises. Where appropriate, references are provided to other guidance documents. •  General freeway geometric and design considerations not unique to managed lanes (27). •  General signing (1). •  Demand forecasting and capacity associated with managed lanes, including detailed discussion of weaving associated with managed lane access. •  Managed lanes not located in a controlled-access environ- ment, such as busways in separate rights-of-way and on arterials (28). •  Conventional toll roads (including variably priced toll roads). •  Rural and intercity highways. •  Other congestion pricing or tolling strategies not affiliated with managed lanes. •  Public–private project implementation not applied to managed lanes. •  Smarter roadway concepts that address all freeway lanes. An example reference includes Highways England’s guid- ance on how to drive on a smart motorway (http://www .highways.gov.uk/our-road-network/managing-our-roads/ improving-our-network/smart-motorways/). •  Active traffic management [except for specific examples applied to managed lanes; see FHWA, Office of Opera- tions (8)]. •  Broad applications of TDM strategies and concepts (10). •  Broad applications of corridor congestion manage ment (12). •  Transit facilities located off a controlled-access roadway (28). •  Fixed-transit guideways (bus, light rail, commuter rail) located within or outside a controlled-access roadway. •  Topics already addressed thoroughly in parallel or legacy guidance and readily available to the practitioner.

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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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