Managed lanes are highway facilities or a set of lanes where operational strategies, such as pricing, vehicle eligibility, access control, traffic control, or a combination of these strategies, are proactively implemented. Numerous domestic and international agencies either have constructed or are planning managed lanes. Each facility is unique and presents issues and challenges since these facilities are often implemented in high-demand, congested, or constrained corridors. There has been no singular national guidance to assist transportation agencies implementing managed lanes. Some information on managed lanes has been included in American Association of State Highway and Transportation Officials and Federal Highway Administration guides, but they do not explicitly address the wide range of issues and complexity associated with the planning, design, operations, and maintenance of managed lanes, and how these factors interact, in sufficient detail to serve as a national guide on the subject. Managed lanes also have unique aspects related to financing, project delivery, public outreach, enforcement, and system integration that should be considered in each step of the project development process. The objective of National Cooperative Highway Research Program (NCHRP) Project 15-49 was to develop guidelines for the planning, design, operations, and maintenance of managed lanes. This final product—NCHRP Research Report 835: Guidelines for Implementing Managed Lanes—was developed to become the primary reference on managed lanes and complement other national guidelines. It was designed to be applicable to practitioners at all levels of experience with managed lanes and to be used to support informed decision making. The scope of this project was limited to managed lanes on freeways and expressways. The tasks and activities completed in NCHRP Project 15-49 to create these guidelines are documented in a separate research report (NCHRP Web-Only Document 224: Research Supporting the Development of Guidelines for Implementing Managed Lanes). Chapter 1 of the guidelines provides an introduction to managed lanes. The initial overview includes an abridged history of managed lanes in the United States, definition of key terms and concepts, and context within which to consider managed lanes. This introductory chapter provides a high-level discussion of some common managed lane designs and strategies, the decision-making process involved in implementing managed lanes, and some safety performance considerations. The chapter concludes by describing the intended audience of the guidelines as practitioners involved in the planning, design, implementation, or operation of a managed lane facility, and it briefly lists topics included and not included within the scope of the document. Chapter 2 focuses on considerations for appropriately planning a managed lane using experience from past projects and other national guidance. Planning a managed lane project usually consists of the following components: • Identifying goals and objectives. • Conceptually planning and testing feasibility. • Refining feasibility to define a project or program. • Developing an appropriate concept of operations and preliminary design that address the project or program. • Developing an implementation plan. • Developing a financing or funding plan. • Pursuing an environmental review (e.g., National Environmental Policy Act, California Environmental Quality Act), if required. Guidance related to each of these components is provided in Chapter 2, along with a discussion of policy and legislative considerations and a discussion on incorporating public involvement and support in the planning process. Chapter 3 contains guidance on the design of managed lane facilities. Intended user groups and design vehicles are presented in the initial section of the chapter, followed by a description of a variety of geometric design considerations. These considerations include consistency among applicable local, regional, state, and national guidelines; design speed; cross section and alignment; location of managed lanes with respect to general-purpose lanes; treatments for separating managed lanes and general-purpose lanes; reversible and contra?flow lanes; pullouts for enforcement or refuge; and issues when converting a high-occupancy vehicle lane to a high-occupancy toll lane. The chapter also provides a section on the provision of access to and from managed lane facilities, including consideration of limited versus continuous access and applicable corresponding treatments. The chapter concludes with a brief discussion of operational impacts on design, including appropriate references to other chapters and sections within these guidelines. Chapter 4 provides information and guidance on appropriate traffic control devices. A description of relevant sections in the Manual on Uniform Traffic Control Devices is provided for the reader’s reference. The chapter describes multiple categories of signs (i.e., guide, regulatory, and changeable), signals, and pavement markings, including devices specific to reversible and contra-flow lanes. Additional methods of disseminating information to road users are discussed, along with guidance for installation and maintenance as well as trade-offs to consider in facilities with constrained designs. Chapter 5 focuses on implementation and deployment of managed lane facilities. Guidance in this chapter includes topics such as reviewing the design and providing for appropriate testing of the system (including toll collection hardware) to accomplish system acceptance. The chapter also includes a brief overview of the importance of accommodating improvements and upgrades, as well as a discussion of the project delivery process. The theme of Chapter 6 is operations and maintenance of managed lane facilities. General issues related to operations include the development of a concept of operations for a facility, considerations for toll operations, and considerations for high-occupancy vehicle eligibility. Additional topics include considerations at startup as well as ongoing operations, business rules for managed lanes, operation of managed lane systems, and performance monitoring and evaluation. The chapter concludes with a discussion of maintenance considerations. This guideline document concludes with a list of commonly used acronyms, a glossary of key terms, and a list of references of other published sources used to develop the guidelines.(Author/publisher)
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