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3 Background Introduction Motorists driving the wrong way on divided roadways has been an area of concern for transportation agencies and the traveling public for over 50 years. Even though wrong-way crashes are infrequent, they are a serious problem because such crashes typically result in death or serious injury to the people involved (NTSB 2012). The first wrong-way driving research in the United States occurred in the mid-1960s (e.g., Tamburri 1965; Tamburri and Theobald 1965). A resurgence of wrong-way driving research and countermeasure imple- mentation has taken place over the last decade due to the high-profile nature of these crashes and the FHWAâs Toward Zero Deaths vision. Numerous previous studies have investigated the nature of wrong-way crashes on controlled-access highways (i.e., freeways) (e.g., Moler 2002; NTSB 2012; Baratian-Ghorghi et al. 2014). Most studies have found that these crashes tend to occur more frequently in urban areas, at night, and on the weekend (e.g., Cooner et al. 2004; Zhou et al. 2012; Finley et al. 2014; Kittelson & Associates, Inc. 2015). Many studies have documented the difficulty with identifying the origination of the wrong-way maneuver onto freeways (Cooner et al. 2004; Lathrop et al. 2010; Morena and Leix 2012; Zhou et al. 2012). Even so, a few studies have determined that most wrong-way maneuvers onto freeways originate at exit ramps (Tamburri and Theobald 1965; NTSB 2012). Many studies have also found that wrong-way drivers involved in crashes on freeways tend to be young males and/or driving under the influence of alcohol and/or drugs (e.g., Tamburri and Theobald 1965; Zhou et al. 2012; Baratian-Ghorghi et al. 2014; Finley et al. 2014). In addition, some studies have found that elderly drivers are over represented in wrong-way crashes on free- ways (NTSB 2012; Baratian-Ghorghi et al. 2014; Kittelson & Associates, Inc. 2015). Less is known about wrong-way crashes on divided high- ways because only a few studies have investigated these types of crashes (Tamburri and Theobald 1965; Vaswani 1977; Athey Creek Consultants 2016). Limited data have shown that most wrong-way entries on divided highways occur at intersections with median openings. Other wrong-way entries have occurred when drivers exited business establish- ments, drove through the median, or made U-turns. A more robust dataset is needed to investigate the characteristics of wrong-way crashes on divided highways and determine the geometric characteristics and traffic control devices that impact their occurrence. Such findings could aid practitio- ners in the deployment of traffic control devices to deter wrong-way movements on divided highways. The 2009 Manual on Uniform Traffic Control Devices (MUTCD) (2009 MUTCD with Revisions 1 and 2, FHWA 2012) contains information regarding the installation of DO NOT ENTER, WRONG WAY, ONE WAY, and other regula- tory signs, as well as pavement markings, to deter wrong-way movements at intersections on divided highways and at exit ramps on freeways. However, inconsistencies between the MUTCD, Policy on Geometric Design of Highways and Streets (AASHTO 2011, also known as the Green Book), and state practice have been identified. Transportation agencies are installing active technologies in an effort to further reduce wrong-way movements onto freeways (e.g., Zhou et al. 2012; American Traffic Safety Services Association 2014; Finley et al. 2014; Ponnaluri 2016). Evaluations that help clarify the incon- sistencies and assess the effectiveness of active technologies are needed to improve the guidance found in the MUTCD. Project Objectives The primary objective of NCHRP Project 03-117 was to examine the characteristics of wrong-way crashes on divided highways and determine the impact of median width and select traffic control devices on their occurrence. A second- ary objective was to identify and determine the effectiveness of emerging countermeasures implemented at freeway exit C H A P T E R 1
4 ramps. To accomplish this, researchers undertook the follow- ing major efforts: ⢠Assessment of data and findings from previous wrong-way driving studies to quantify crash characteristics, identify countermeasures, and assess the effectiveness of counter- measures; ⢠Comprehensive review of the MUTCD regarding wrong- way movement signing and markings at freeway ramps and non-signalized divided highway crossings; ⢠Analysis of the effects of median width and traffic control devices upon wrong-way crashes on high-speed rural and urban divided highways using a multistate dataset devel- oped under this research effort; ⢠Evaluation of the effectiveness of LEDs within the border of WRONG WAY signs and red RFBs above and below WRONG WAY signs at freeway exit ramps; and ⢠Development of proposed changes to the MUTCD based on the findings of the research. The detailed results of the efforts regarding the first and second bullets above, as well as the detailed proposed changes to the MUTCD, are located in the appendices. This report specifically addresses the methodology and results of the third and fourth bullets above. Some of the findings from the literature review and review of the MUTCD appear through- out the report as specific topics are discussed. Definitions Throughout this report, the term âfreewayâ refers to a multi- lane highway with fully controlled access (i.e., vehicles can only enter and exit at designated ramps). The term âdivided highwayâ refers to a multilane, non-freeway facility where the opposing travel directions are separated by a median. Divided highways typically have at-grade intersections and no control of access between intersections (i.e., direct driveway access allowed). Divided highways do not include roadways with continuous, two-way left-turn lanes. In this study, the median width was defined as the area between the inside edge of the traveled way of the near travel lane or left-turn lane, if present, to the inside edge of the trav- eled way of the opposing through lane. This measurement included the inside shoulders, but not left-turn lanes. This definition matches the one used in the MUTCD in order to correlate interactions between the median width and traffic control devices. The medians were either raised (i.e., curb) or depressed (i.e., landscape). High-speed divided highways had a posted speed limit greater than or equal to 50 mph, and low-speed divided high- ways had a posted speed limit less than or equal to 45 mph. These definitions are consistent with the Green Book (AASHTO 2011), the Texas Roadway Design Manual (Texas DOT 2014), the Manual on Uniform Standards for Design, Construction, and Maintenance for Streets and Highways (Florida DOT 2013), and the California Highway Design Manual (Caltrans 2016). Urban areas were defined as those having a population of 5000 or more. Rural areas were outside the boundaries of urban areas and had a population less than 5000. These defi- nitions are consistent with the Green Book, the Texas DOT Crash Records Information System (CRIS), and the RCI [Roadway Characteristics Inventory] Features and Character- istics Handbook (Florida DOT 2014). Contents of This Report This technical report documents the methodology and results of the various research activities performed in this project. Following this introductory chapter, Chapter 2 presents the data, methodology, and results of the analy- sis of wrong-way driving crashes on high-speed rural and urban divided highways correlated to median width and traffic control devices. Chapter 3 then presents the data, methodology, and results of two separate analyses conducted to determine the effectiveness of LEDs within the border of WRONG WAY signs and RFBs above and below WRONG WAY signs at freeway exit ramps. Finally, Chapter 4 presents a summary of the key findings from these efforts and pro- vides an overview of the suggested changes to the MUTCD. Appendix A contains a summary of the domestic and inter- national research reviewed. Appendix B provides an overview of the applicable MUTCD sections and figures, as well as other pertinent documents. Appendix C contains the detailed suggested revisions to the 2009 MUTCD (FHWA 2012).
