Grady Carrick

Wrong-Way Driving: Multifactor Risk-Based Model for Florida Interstates and Toll Facilities

Wrong-way driving (WWD) is one of the most dangerous driver errors or behaviors on limited access facilities. Previous studies focused on analyzing WWD crashes but discovered that WWD crashes were extremely rare. Using WWD 911 calls and WWD citations, which occur much more frequently than WWD crashes, to help predict WWD risk allows roadway agencies to be proactive and implement WWD countermeasures at problem areas instead of waiting for serious WWD crashes to occur. This study developed a model to determine WWD risk according to WWD crashes, citations, and 911 calls. For the development of this novel model, a market basket analysis was used to determine the overlap between the three WWD data sets (crashes, 911 calls, and citations for the years 2011 and 2012 on Florida Interstates and toll roads). The independent WWD events were then used to develop a generalized Poisson regression model that allowed the WWD 911 calls, citations, and crash frequencies to be converted to WWD risk values. WWD risk densities were also calculated by using either vehicle miles traveled or roadway length to consider exposure. The counties and roadways were then ranked with respect to WWD risk values and densities; these rankings indicated that Miami–Dade was a problematic county because it was ranked highest by WWD risk value and its nine Interstates or toll roads were ranked in the top 15 by WWD risk density. The developed model and macroscopic rankings are very useful to help identify counties and roadways where WWD countermeasures should be implemented.

Modeling the Risk of Wrong-Way Driving on Freeways and Toll Roads

Wrong-way driving (WWD) is dangerous and poses a significant legal and safety risk when it occurs on limited access facilities. Most previous studies focused on WWD crashes to develop countermeasures. The combined risk of WWD citations and 911 calls, however, has been overlooked. Furthermore, because WWD crashes are rare and represent less than 3% of all crashes, such crashes are difficult to analyze. WWD prediction is an important assessment because it can help mitigate and reduce future occurrences. This paper builds on previous work pioneered by the authors in which WWD crashes were predicted with the use of WWD noncrash events (e.g., citations and 911 calls). These WWD noncrash events occur more frequently, and their data are widely available. The paper demonstrates how WWD 911 calls and citations, along with route characteristics, can be linked to WWD crashes and so target corridors for countermeasures. Two models were developed and applied in South Florida to identify WWD hot spots. The first model shows that WWD citations and 911 calls positively affect yearly crash prediction. The second model identifies hot spot segments in a route and predicts crashes during a 4-year period. This second model predicts crashes with the use of several variables, such as major interchanges per mile, directional interchanges per mile, and WWD 911 calls along the segment. The findings showed high WWD risk values on SR-821 (Homestead Extension) from Exits 20 to 39 and on SR-9 (I-95) from Exits 0 to 6B and Exits 7 to 14.

Enforcement Engineering: Conceptual Exploration for New Engineering Discipline:

The determination of where, when, how, and which laws to enforce is as varied as the number of police officers on the street. Traffic enforcement decisions range from macroscopic choices such as resource allocation at the organizational level to the microscopic options individual officers have in dispensing tickets. Everything between those extremes speaks to the proposition of where, when, and which laws to enforce, with the stated objective of reducing crashes. The concept of “engineering” traffic enforcement implies the use of scientific principles to guide the full range of enforcement decisions so as to evolve stated safety intentions into definable safety objectives. This approach offers the potential to create greater efficiency and effectiveness for enforcement agencies, which is important in an age of fierce competition for public dollars. The framework of enforcement engineering consists of information-driven problem identification, the application of evidence-based solutions, and the use of empirical performance measurement. This paper advances a conceptual exploration for enforcement engineering to promote more targeted, effective, and defensible traffic enforcement.

Law Enforcement Vehicle Crashes in Florida: Descriptive Analysis and Characterization

This study analyzed 31,438 reported crashes that involved 33,638 law enforcement vehicles, 27,723 non–law enforcement vehicles, 463 pedestrians, and 391 bicyclists that occurred in Florida from 2005 through 2008. These crashes resulted in more than

Methodological Approach to Spatiotemporal Optimization of Rural Freeway Enforcement in Florida

101 million in total damages, 10,124 injuries, and 88 fatalities. The law enforcement vehicle crashes could be characterized by descriptive techniques such as frequencies analysis and cross-tabulation. This study found that the typical law enforcement crash was a low-speed event on a local street. Stop and signalized intersection locations were well represented in the data. The law enforcement vehicle commonly moved straight, slowed, and stopped or was parked when it crashed. Rear-end and backing-type crashes were common. Most crashes occurred during the daytime, under favorable driving conditions, and during routine operating mode. Most of the time, the driver of the law enforcement vehicle did not contribute to the cause of the collision, and the vast majority of crashes did not result in any injury. Typically, law enforcement vehicles were driven away from the scene of the collision, and total damages averaged slightly more than

Development of Guidance for Deployment Decisions on Safety Service Patrols in Florida

3,000. Pursuit and emergency operation mode crashes made up about 23% of the crashes. In these operating conditions, vehicle speed, injury severity, and damages all increased, although the culpability of the law enforcement vehicle operator usually did not. The environmental conditions for emergency mode were not significantly different than for other crashes.

The move over law: effect of emergency vehicle lighting on driver compliance on Florida freeways

For years, scientists and safety advocates have used various statistical methods to understand when, where, and why traffic crashes happen. Improved traffic crash data systems, including the geographic information system (GIS), are helping to identify when, where, and why traffic crashes occur. Because the vast majority of motor vehicle traffic crashes are attributed to some type of driver error, the need for traffic law enforcement is evident. Traffic law enforcement holds the promise of being an effective part of regulating and modifying the behavior of drivers, and, therefore, it is part of an effective countermeasure strategy. GIS and other methods have been used to identify problem locations or hot spots, but networkwide crashes and enforcement have not traditionally been considered. If a general deterrent effect is derived from visible traffic law enforcement, then when and where the countermeasure is applied become prominent. This research used GIS to spatially relate nearly 10,000 crashes and more than 179,000 citations issued on approximately 800 mi of rural freeways in Florida. Traffic volume data were used to normalize the data set and were analyzed with descriptive statistics and enforcement-to-crashes ratios. When historical crash data and historical enforcement data were related, significant spatial and temporal misalignment was apparent. Opportunities to optimize the time and place of traffic enforcement were identified through this analysis.

Evaluating Wrong-Way Driving Characteristics, Countermeasures, and Alert Dissemination Methods through Driver and Law Enforcement Surveys

This research had the objective of providing a decision support system for managers who must decide whether a roadway warrants the addition of a safety service patrol (SSP). Unlike the familiar signal warrants that guide the installation of traffic signals at candidate intersections, no such guidelines exist for decisions on SSPs. A proven framework for deploying intelligent transportation system equipment is adapted for this purpose. Meetings with managers from the service patrol program of the Florida Department of Transportation and a survey of national state points of contact for service patrols provided insight into critical factors that might contribute to guidelines. Historical incidents from Florida fed models that predict incidents and crashes on candidate roadways by using proven negative binomial regression models like those found in the Highway Safety Manual. Qualitative and quantitative thresholds for critical factors were established in the form of rules in decision tables that, when evaluated, render recommended actions for decisions on SSPs. The critical factors, thresholds, and use of decision tables proved to be an effective means by which to guide deployment decisions on SSPs, as evidenced by testing with a candidate roadway in Florida. Ultimately, computer software, with a graphical user interface, facilitated the collection of needed information, analysis, and recommendations in implementation of the guidelines.

Analysis of Performance Data Collected from Two Wrong-Way Driving Advanced Technology Countermeasures and Results of Countermeasures Stakeholder Surveys

Police traffic enforcement is a common, recognizable part of the driving environment. As with those in other professions working near roadways, officers are at increased danger when they have stopped on the shoulder. Statistics from the Federal Bureau of Investigation indicate that from 2000 to 2009, 47 U.S. officers were killed while performing traffic stops and 73 were killed while directing traffic or assisting motorists; 101 officers were killed feloniously while conducting traffic stops. To mitigate dangers, every state except Hawaii has implemented a law requiring drivers to move over or slow down when approaching a patrol vehicle stopped at roadside. This research observed the behavior of more than 9,000 right-lane vehicles passing staged police stops on Florida freeways in north and central Florida. Each staged stop involved the use of a civilian research vehicle, a marked police vehicle, video recording of passing traffic, and measurement of passing vehicle speeds with a laser speed measurement device. Overall compliance with the move over component of the Florida laws was 75.9%, but compliance with the legal requirement to slow to 20 mph below the speed limit when not moving over was just 5.8%. Examination of patrol vehicle emergency lighting configurations determined that the use of blue and red emergency lights increased compliance in a statistically significant way, to nearly 80%, versus 68.8% when only amber lights were used. Additionally, when blue and red lights were not used, driver merge maneuvers were executed closer to the stop, and mean speeds of non–move over vehicles were higher.

Methods for the Design of Safety Service Patrol Beats: The Florida Road Ranger Case Study

Wrong-way driving (WWD) on limited-access highways is a serious driver error that could be fatal for both the wrong-way driver and right-way drivers. Agencies and law enforcement officers (LEOs) can spend valuable time and resources responding to WWD events. A survey of 247 LEOs found that despite being dispatched multiple times per year in response to WWD, most issue fewer than one WWD citation per year. In the survey, LEOs also gave their perspectives on the characteristics of WWD events and the influences behind WWD. Agencies typically use dynamic message signs (DMS) for notifying right-way drivers of WWD events, but little research has considered solutions that are less costly and potentially farther-reaching. A survey of 900 Florida toll-road drivers found that drivers rely on navigation devices, apps, or both, significantly more than DMS for traveler information. Drivers were receptive to receiving WWD alerts through navigation services and indicated that they would react to WWD events in a way that is beneficial to highway safety. Crowdsourcing technologies were considered to generate WWD information and quickly disseminate alerts to drivers and officers. Additional survey questions answered by a combined group of 2,052 drivers, LEOs, and agency officials determined that among advanced WWD countermeasures, most preferred two sets of “Wrong Way” signs equipped with rectangular flashing beacons over one set of signs with light emitting diodes. Combining advanced countermeasures with innovative right-way driver notification methods could enhance law enforcement efficiency, reduce WWD crashes, and provide safer conditions for both drivers and officers.