According to Florida Department of Highway Safety and Motor Vehicles, there were 1,490 wrong-way driving (WWD) crashes in the state in 2015, resulting in almost as many injuries and 96 fatalities. In the years 2013-2015, there were more than 4,300 total injuries due to WWD crashes on Florida roads.
While WWD crashes are relatively few, they are random and often lead to head-on collisions. As such, the fatality and serious injury rates in WWD incidents are much higher than in other crash types.
FDOT has developed a comprehensive WWD mitigation initiative. As part of that effort, FDOT has partnered with Florida International University (FIU) to conduct research aimed at mitigating this crash type.
Beyond WWD Hotspots
There are several effective countermeasures for mitigating WWD crashes, but deploying them in the most relevant locations can be a challenge. Traditional approaches rely on screening a roadway network to identify “hotspots,” or locations with multiple crashes of a particular type. Practitioners identify the hotspots and then implement appropriate countermeasures at those locations.
Hotspot analysis is insufficient to address WWD crashes for two reasons. First, WWD incidents are fewer in number than other crash types and spread over many disparate locations. There are rarely enough crashes at any one location to create a hotspot cluster. Second, WWD crashes are unique in that they can happen miles from where the driver’s original mistake was made.
“Knowing where the crash happened is not enough,” said Dr. Priyanka Alluri, Assistant Professor at FIU and Principle Investigator for the project. “To mitigate wrong-way crashes, we have to identify the point where the driver actually entered the roadway the wrong way. That is sometimes several miles from where the crash happens.”
In addition, the hotspot approach is reactive, based on responding to past crashes. A more effective approach would be proactive, identifying the locations at highest risk for WWD and focusing investments there, before crashes happen.
This leaves practitioners with two fundamental questions regarding WWD mitigation: Which countermeasures should be used and, more importantly, where should they be installed?
A Broader Perspective
Instead of focusing on hotspots of past crashes, the researchers for this project explored whether they could identify certain pre-conditions that make areas more susceptible to future WWD crashes.
“Wrong-way crashes are relatively random and don’t lend themselves to traditional analysis methods,” said Dr. Raj Ponnaluri, FDOT Connected Vehicles and Arterial Management Engineer, and Project Manager for the research effort. “So we asked ourselves, ‘Is there a role for non-engineering elements?’”
The team hypothesized that if they could discover the overall demographic and land-use conditions that correlated with certain WWD crashes, then they could identify specific regions that were at risk. Agencies would then have the information they needed to proactively target countermeasure investments to high-risk areas. This method represented a significant departure from traditional hotspot analysis.
“There is an inherent sense to a risk-based approach,” Alluri said. “But it is still a paradigm shift.”
While the elements contributing to WWD incidents vary widely, studies have indicated that certain socioeconomic and demographic factors may heighten the risk of wrong-way driving. So, the research team conducted a statewide macroscopic analysis of socioeconomic, demographic, and neighborhood land-use characteristics to provide a more holistic and accurate picture of those factors.
“This spatial analysis moved us beyond a corridor-level detail,” Ponnaluri said.
The team chose three broad demographic categories to study –drivers aged 65 years and older, tourists, and impaired drivers under the influence of drugs or alcohol.
They then assessed the land-use characteristics that relate to those demographics. For instance, locations with a relatively high density of senior population and health facilities could be more prone to WWD incidents involving drivers aged 65 years and older. For impaired drivers, it was assumed that areas with establishments that sell alcohol would be more likely to have WWD crashes nearby. As such, information on restaurants, night clubs, bars, and cocktail lounges was included in the analysis.
One by one, the team used “heat maps” to overlay statewide WWD crash data onto the chosen demographic and land-use factors. The results were telling.
“There was a very strong correlation between establishments that dispense alcohol and wrong-way crashes involving impaired drivers,” Alluri said. “There was some correlation between the presence of senior population and health facilities and wrong-way crashes involving drivers aged 65 years and older; and no significant correlation between tourist attractions and wrong-way crashes involving tourists.”
The research findings can provide agencies a firmer ground on which to base their choices. “This will let the FDOT Districts make data-based decisions about where to focus their energies and investments,” Ponnaluri said.
Customized Solutions, Widespread Benefits
Knowing the best locations to implement countermeasures is the first crucial step. But one countermeasure does not fit all. Just as demographic and land-use characteristics correlate to different types of WWD drivers, certain countermeasures are more effective with each type. Knowing the type of WWD drivers in an area will allow agencies to tailor their countermeasures to those situations.
“For instance, we know that impaired drivers tend not to use their peripheral vision. They look only in front of them,” Alluri said. “So we might recommend WWD countermeasures that are in direct view and in drivers’ cone of vision at locations that are prone to impaired drivers.”
This data-based approach also provides valuable information for non-transportation entities.
“Knowing at-risk locations helps law enforcement focus their efforts and deploy their resources in the areas where they can be most effective,” Ponnaluri said.
Planning for Success
The long-term goal of this research is to develop a strategic countermeasure implementation plan that prioritizes WWD areas in each FDOT District and specifies countermeasures to deploy at the high-risk locations.
The plan should streamline efforts to mitigate WWD incidents statewide and provide a sound approach to WWD analysis going forward.
“This project is implementation based,” Alluri said. “We want to assist the FDOT Districts to mitigate WWD incidents by answering those two specific questions: Where to install WWD countermeasures and which countermeasure(s) to install?”