Identification and Evaluation of the Cost-Effectiveness of Highway Design Features to Reduce Nonrecurrent Congestion (2014)

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TRANSPORTATION RESEARCH BOARD WASHINGTON, D.C. 2014 www.TRB.org The Second S T R A T E G I C H I G H W A Y R E S E A R C H P R O G R A M REPORT S2-L07-RR-1 Identification and Evaluation of the Cost-Effectiveness of Highway Design Features to Reduce Nonrecurrent Congestion IngrId B. Potts, douglas W. HarWood, JessIca M. Hutton, cHrIs a. Fees, KarIn M. Bauer, and lIndsay M. lucas MRIGlobal cHrIstoPHer s. KInzel and roBert J. FrazIer HDR Engineering, Inc.

Subscriber Categories Highways Operations and Traffic Management Planning and Forecasting

SHRP 2 Reports Available by subscription and through the TRB online bookstore: www.TRB.org/bookstore Contact the TRB Business Office: 202-334-3213 More information about SHRP 2: www.TRB.org/SHRP2 The Second Strategic Highway Research Program America’s highway system is critical to meeting the mobility and economic needs of local communities, regions, and the nation. Developments in research and technology—such as advanced materials, communications technology, new data collection tech- nologies, and human factors science—offer a new opportunity to improve the safety and reliability of this important national resource. Breakthrough resolution of significant transportation problems, however, requires concentrated resources over a short time frame. Reflecting this need, the second Strategic Highway Research Program (SHRP 2) has an intense, large-scale focus, integrates multiple fields of research and technology, and is fundamentally different from the broad, mission-oriented, discipline-based research programs that have been the mainstay of the highway research industry for half a century. The need for SHRP 2 was identified in TRB Special Report 260: Strategic Highway Research: Saving Lives, Reducing Congestion, Improving Quality of Life, published in 2001 and based on a study sponsored by Congress through the Transportation Equity Act for the 21st Century (TEA-21). SHRP 2, modeled after the first Strategic Highway Research Program, is a focused, time- constrained, management-driven program designed to com- plement existing highway research programs. SHRP 2 focuses on applied research in four areas: Safety, to prevent or reduce the severity of highway crashes by understanding driver behavior; Renewal, to address the aging infrastructure through rapid design and construction methods that cause minimal disruptions and produce lasting facilities; Reliability, to reduce congestion through incident reduction, management, response, and mitigation; and Capacity, to integrate mobility, economic, environmental, and community needs in the planning and designing of new trans- portation capacity. SHRP 2 was authorized in August 2005 as part of the Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users (SAFETEA-LU). The program is managed by the Transportation Research Board (TRB) on behalf of the National Research Council (NRC). SHRP 2 is conducted under a memo- randum of understanding among the American Association of State Highway and Transportation Officials (AASHTO), the Federal Highway Administration (FHWA), and the National Academy of Sciences, parent organization of TRB and NRC. The program provides for competitive, merit-based selection of research contractors; independent research project oversight; and dissemination of research results. SHRP 2 Report S2-L07-RR-1 ISBN: 978-0-309-27364-0 Library of Congress Control Number: 2014937962 © 2014 National Academy of Sciences. All rights reserved. Copyright Information Authors herein are responsible for the authenticity of their materials and for obtaining written permissions from publishers or persons who own the copy- right to any previously published or copyrighted material used herein. The second Strategic Highway Research Program grants permission to repro- duce material in this publication for classroom and not-for-profit purposes. Permission is given with the understanding that none of the material will be used to imply TRB, AASHTO, or FHWA endorsement of a particular prod- uct, method, or practice. It is expected that those reproducing material in this document for educational and not-for-profit purposes will give appropriate acknowledgment of the source of any reprinted or reproduced material. For other uses of the material, request permission from SHRP 2. Note: SHRP 2 report numbers convey the program, focus area, project number, and publication format. Report numbers ending in “w” are published as web documents only. Notice The project that is the subject of this report was a part of the second Strategic Highway Research Program, conducted by the Transportation Research Board with the approval of the Governing Board of the National Research Council. The members of the technical committee selected to monitor this project and to review this report were chosen for their special competencies and with regard for appropriate balance. The report was reviewed by the technical committee and accepted for publication according to procedures established and overseen by the Transportation Research Board and approved by the Governing Board of the National Research Council. The opinions and conclusions expressed or implied in this report are those of the researchers who performed the research and are not necessarily those of the Transportation Research Board, the National Research Council, or the program sponsors. The Transportation Research Board of the National Academies, the National Research Council, and the sponsors of the second Strategic Highway Research Program do not endorse products or manufacturers. Trade or manufacturers’ names appear herein solely because they are considered essential to the object of the report.

The National Academy of Sciences is a private, nonprofit, self-perpetuating society of distinguished scholars engaged in scientific and engineering research, dedicated to the furtherance of science and technology and to their use for the general welfare. On the authority of the charter granted to it by Congress in 1863, the Academy has a mandate that requires it to advise the federal government on scientific and technical matters. Dr. Ralph J. Cicerone is president of the National Academy of Sciences. The National Academy of Engineering was established in 1964, under the charter of the National Academy of Sciences, as a parallel organization of outstanding engineers. It is autonomous in its administration and in the selection of its members, sharing with the National Academy of Sciences the responsibility for advising the federal government. The National Academy of Engineering also sponsors engineering programs aimed at meeting national needs, encourages education and research, and recognizes the superior achieve- ments of engineers. Dr. C. D. (Dan) Mote, Jr., is president of the National Academy of Engineering. The Institute of Medicine was established in 1970 by the National Academy of Sciences to secure the services of eminent members of appropriate professions in the examination of policy matters pertaining to the health of the public. The Institute acts under the responsibility given to the National Academy of Sciences by its congressional charter to be an adviser to the federal government and, on its own initiative, to identify issues of medical care, research, and education. Dr. Victor J. Dzau is president of the Institute of Medicine. The National Research Council was organized by the National Academy of Sciences in 1916 to associate the broad community of science and technology with the Academy’s purposes of furthering knowledge and advising the federal government. Functioning in accordance with general policies determined by the Academy, the Council has become the principal operating agency of both the National Academy of Sciences and the National Academy of Engineering in providing services to the government, the public, and the scientific and engineering communities. The Council is administered jointly by both Academies and the Institute of Medicine. Dr. Ralph J. Cicerone and Dr. C. D. (Dan) Mote, Jr., are chair and vice chair, respectively, of the National Research Council. The Transportation Research Board is one of six major divisions of the National Research Council. The mission of the Transportation Research Board is to provide leadership in transportation innovation and progress through research and information exchange, conducted within a setting that is objective, interdisci- plinary, and multimodal. The Board’s varied activities annually engage about 7,000 engineers, scientists, and other transportation researchers and practitioners from the public and private sectors and academia, all of whom contribute their expertise in the public interest. The program is supported by state transportation departments, federal agencies including the component administrations of the U.S. Department of Transporta- tion, and other organizations and individuals interested in the development of transportation. www.TRB.org www.national-academies.org

SHRP 2 STAFF Ann M. Brach, Director Stephen J. Andrle, Deputy Director Neil J. Pedersen, Deputy Director, Implementation and Communications Cynthia Allen, Editor Kenneth Campbell, Chief Program Officer, Safety JoAnn Coleman, Senior Program Assistant, Capacity and Reliability Eduardo Cusicanqui, Financial Officer Richard Deering, Special Consultant, Safety Data Phase 1 Planning Shantia Douglas, Senior Financial Assistant Charles Fay, Senior Program Officer, Safety Carol Ford, Senior Program Assistant, Renewal and Safety Jo Allen Gause, Senior Program Officer, Capacity James Hedlund, Special Consultant, Safety Coordination Alyssa Hernandez, Reports Coordinator Ralph Hessian, Special Consultant, Capacity and Reliability Andy Horosko, Special Consultant, Safety Field Data Collection William Hyman, Senior Program Officer, Reliability Linda Mason, Communications Officer Reena Mathews, Senior Program Officer, Capacity and Reliability Matthew Miller, Program Officer, Capacity and Reliability Michael Miller, Senior Program Assistant, Capacity and Reliability David Plazak, Senior Program Officer, Capacity and Reliability Rachel Taylor, Senior Editorial Assistant Dean Trackman, Managing Editor Connie Woldu, Administrative Coordinator ACKNOWLEDGMENTS This work was sponsored by the Federal Highway Administration in cooperation with the American Association of State Highway and Transportation Officials. It was conducted in the second Strategic Highway Research Program (SHRP 2), which is administered by the Transportation Research Board of the National Academies. The project was managed by Ralph Hessian, SHRP 2 Special Consultant, Capacity and Reliability. The research reported in this document was performed by MRIGlobal, supported by HDR Engineering, Inc. Ingrid Potts, MRIGlobal, was the principal investigator. The other authors of this report include Douglas Harwood, Jessica Hutton, Chris Fees, Karin Bauer, and Lindsay Lucas of MRIGlobal and Christopher Kinzel and Robert Frazier of HDR Engineering, Inc. The authors acknowledge the contributions to this research from John O’Laughlin of Delcan and Rachel Powers of Vector Communications. The authors also acknowledge all the states and highway agencies that contributed to the research, most especially the four highway agencies that hosted focus groups: the Georgia Department of Transportation, the Maryland Department of Transportation, the Minnesota Department of Transportation, and the Port Authority of New York and New Jersey.

F O R EWO R D Ralph Hessian, P.Eng., FITE, SHRP 2 Special Consultant, Capacity and Reliability This research report presents the findings on the identification and evaluation of the use of highway geometric design features on freeways to reduce nonrecurrent congestion and improve travel time reliability. General guidance is provided on the range of design elements that could be used by transportation agencies to improve travel time reliability and reduce nonrecurrent congestion, analysis procedures and models to measure their operational and safety effectiveness, as well as a life-cycle benefit–cost method to support decision making on the possible use of individual treatments to address actual nonrecurring traffic condi- tions. For the safety effectiveness analysis, a new relationship between safety and congestion was explored and a mathematical model developed to quantify crash frequency at various levels of service. Traffic congestion continues to grow on the nation’s highways, which is increasing the con- cerns of transportation agencies, the business community, and the general public. Conges- tion includes recurring and nonrecurring components. Recurring congestion reflects routine day-to-day delays during specific time periods where traffic demand exceeds available roadway capacity. Road users have come to expect these daily traffic patterns and adjust their travel plans accordingly to achieve timely arrivals. Nonrecurring congestion that causes unexpected extra delays results from random incidents, such as crashes, weather, and work zones. Road users are frustrated by these unexpected delays that can make for unreliable arrival times at their destina- tions. The SHRP 2 Reliability research objective focuses on reducing nonrecurring congestion through incident reduction, management, response, and mitigation. Achieving this objective will improve travel time reliability for both people and freight. Highway geometric design, which involves the provision of physical elements and their dimensions, plays a major contributory role in the traffic operations conditions and safety performance results on highway facilities. Current design standards and guidance manuals do not address the use and effectiveness of design elements as an explicit countermeasure to prevent or mitigate the negative effects of nonrecurring factors and events that happen on a regular basis causing unreliable travel for highway users. This research seeks to better understand how different geometric design elements can contribute to more-reliable travel times and develop procedures that will allow agencies and professional practitioners to eval- uate the cost-effectiveness of alternative design elements as a potential solution to specific nonrecurring conditions. The research team established a list of the physical design elements that could be used to influence nonrecurring congestion. Guidance based on published information and inter- views with select transportation agencies is provided for each element. This guidance pro- vides information on advantages and disadvantages, typical applications, expected benefits, factors to consider when selecting the treatment, design criteria, operational and safety effectiveness, and costs. In addition, analysis procedures and models were developed to provide the quantitative measurement of the operational effectiveness, safety effectiveness, and life-cycle cost–benefit results to estimate the potential impact of any candidate design element to improve travel time reliability and reduce nonrecurring congestion.

This research has generated two companion products that allow transportation agen- cies and professionals to apply these research findings effectively in daily practice. These products are the Design Guide for Addressing Nonrecurrent Congestion, which is a cata- logue of the design elements and their associated use information, and the Analysis Tool for Design Treatments to Address Nonrecurring Congestion, which is a tool to execute the various analysis procedures and models to measure the effectiveness of a design element on travel time reliability.

C O N T E N T S 1 Executive Summary 4 CHAPTER 1 Introduction 4 Background 11 Organization of the Report 12 CHAPTER 2 Research Approach 12 Research Objective and Scope 13 Evolution of Research Approach for Traffic Operational Analysis 13 Products of the Research 14 Design Guide 14 Analysis Tool 15 Dissemination Plan 16 CHAPTER 3 Data Collection and Documentation of Current Design Practice 16 Reliability Models from SHRP 2 Project L03 17 Assembly of Databases 18 Review of Completed and Ongoing Research 18 Initial Contacts with Highway Agencies 19 Focus Groups with Highway Agencies 20 Workshops with Highway Agencies to Discuss Weather Treatments 20 Meetings with Highway Agencies to Obtain Detailed Information About Design Treatments 21 List of Design Treatments 24 CHAPTER 4 Traffic Operational Assessment 24 Overview 24 Prediction of Cumulative TTI Curve 31 Quantifying Design Treatment Effects on Reliability by Using the Cumulative TTI Curve 40 CHAPTER 5 Safety Assessment of Design Treatments 40 Direct Effects of Design Treatments on Safety 41 Development of Congestion–Safety Relationship 49 Prediction of Crash Reduction Due to Congestion Reduction Resulting from Design Treatments 51 Estimation of Crash Distributions by Hour of Day

53 CHAPTER 6 Life-Cycle Benefit–Cost Analysis 53 Overview of Life-Cycle Benefit–Cost Analysis Methodology 55 Values of Travel Time and Reliability 59 Costs of Crashes 60 CHAPTER 7 Analysis Tool and Underlying Equations: Test for Reasonableness 60 Objective 60 Approach 60 Initial Results of Reasonableness Tests 61 Adjustments to Defaults 62 Final Results of Reasonableness Tests 70 Findings of Reasonableness Tests 71 CHAPTER 8 Conclusions and Recommendations 71 Conclusions of the Research 74 Recommendations for Implementation of Research Results and Future Research Needs 75 References 77 Appendix A. Background Information for Model Development Online version of this report: www.trb.org/Main/Blurbs/169767.aspx.