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Introduction 3 This definition includes trucks with a gross vehicle weight or gross combination weight rating of at least 26,001 lbs, trucks carrying hazardous materials requiring placarding (same as Part 390), and vehicles carrying 16 or more passengers, including the driver. Finally, FHWA classifies nonpassenger vehicles by the number of axles and number of units, as opposed to the FMCSA's definition based on weight or commodity. Single- and multi-trailer trucks (i.e., not single unit trucks), for example, fall within Classes 8 to 13 in FHWA's scheme. The Technical Panel agreed with the project team's recommendation that the types of vehicles included in the CMV definition for this project will be directly dependent on the types of vehicles best served by various CMV-only lane configurations and not tied to any of the federal definitions. Consequently, as trucks are implicitly the focus of this research, passenger vehicles falling under the CMV classifications under federal regulations (discussed previously) will not be included as CMVs. Since the work approach for this project involves analyzing different types of truck-only lane configurations, flexibility in the CMV definition has been adopted to accommodate different types of trucks, based on the type of application of truck-only lanes (note that the terms "CMV- only" and "truck-only" generally will be used interchangeably in this report). 1.3 Overview of the Report The interim report presented an extensive compendium of information about CMV-only lanes and identifies major issues and concepts that should be understood in developing new applications of CMV-only lane concepts. Since this compendium will be a useful planning reference for prac- titioners, it is reproduced in its entirety as Appendix A of this final report. The appendices of the interim report, which are also included as appendices to this final report, provide a detailed bibliography of references including an evaluation of the types of information available from major sources, and a compilation of data tables developed from the major sources. These data tables provide additional material that practitioners can use to support their own analyses of CMV-only lanes. In order to provide background on key concepts and to introduce some of the primary data sources that can be used in evaluating CMV-only lane concepts, Chapter 2 of this final report pro- vides a summary of the interim report. This sets the stage for the analytical elements of the final report, which are contained in Chapter 3, Performance Evaluation, and Chapter 4, Benefit-Cost Analysis. Chapters 3 and 4 draw data from other studies and provide a consistent framework for comparing various CMV-only lane configurations with each other and with other types of road- way capacity improvements. The general approach used in these evaluations was to define two pri- mary scenarios--long-haul intercity corridors and congested urban corridors--to develop a series of relevant alternatives for each scenario, and then to conduct sensitivity tests for the impact of other features (such as tolling). The performance evaluations examine measures of effectiveness related to congestion, reliability, and safety impacts. In Chapter 4, the benefits of the alternatives described in the performance evaluations are monetized and benefit-cost (B-C) comparisons are conducted. Chapter 5 presents the conclusions and recommendations of this study effort. Since the data used in the performance evaluations and B-C comparisons are drawn from various studies using different assumptions, traffic conditions, and analytical procedures, much of the ana- lytical effort was associated with adjusting the results to provide comparability. Wherever appro- priate, results are provided in ranges. A main finding of the background review of existing literature that was conducted for the interim report is that while there is a substantial body of information on CMV-only lanes from planning and feasibility studies, there are very few real-world applications of the concept. Actual

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4 Separation of Vehicles--CMV-Only Lanes applications of concepts that are in some way related to CMV-only lane concepts fall into the fol- lowing categories: Dual-dual1 roadways that provide separated lanes for autos only (an example of which is the New Jersey Turnpike); Lane restrictions for trucks in right-hand lanes; Interchange by-passes for trucks (examples of which are found on I-5 outside of Portland, Oregon, and on I-5 in California at the SR 14/I-5 interchange, the I-5/I-405 interchanges in both the north [San Fernando Valley] and south [Orange County]); Truck climbing lanes on high grades (an example of which is found on I-10 in San Bernardino County, California, between Redlands and Yucaipa); and Short connectors from major port/intermodal facilities to freeways (an example of which is found on the A-20 motorway connecting the Port of Rotterdam with the A-16 motorway). These applications are quite limited, and they do not correspond to the types of approaches of most interest in the various feasibility and planning studies that have been conducted in North America and Europe over the last 20 years, which have focused more on long-haul multistate cor- ridors or major urban freight corridors. The limited data available from these real-world applica- tions makes it difficult to conclusively evaluate certain performance features of CMV-only lanes, particularly the safety and reliability benefits. Nonetheless, where these data are available they have been used in this study to validate certain conclusions about anticipated performance benefits of CMV-only lanes. Although there is limited real-world application of CMV-only lanes, the literature review con- ducted for the interim report shows that there is a substantial number of references to CMV-only lane topics. The preponderance of information was found in planning, policy, and feasibility stud- ies with limited real-world application of the truck-only lane concept. It also was noted in the interim report that there is limited information in the areas of ITS applications and LCVs. Thus, much of the source data on these configurations of CMV-only lanes draw heavily on the work of a limited number of researchers. 1 As noted, dual-dual roadways are comprised of dedicated lanes for autos, along with general purpose (mixed- flow) lanes with auto and truck traffic (trucks are restricted to the general purpose lanes and are not allowed to operate on the auto-only lanes). The terminology "dual-dual roadway" is used by the New Jersey Turnpike Authority to refer to sections along the New Jersey Turnpike with auto-only and general purpose lanes. These sections are also sometimes referred to as "dual roadway" sections.