With over 80,000 miles of roadway under its jurisdiction, the North Carolina Department of Transportation (NCDOT) is responsible for one of the nation’s largest highway systems, and proactively seeks low-cost, high-return safety solutions to protect road users. Each year, 300 fatalities and 1,100 serious injuries occur at rural North Carolina intersections. Frontal impact crashes are a predominant crash type at these intersections and include crash types associated with higher severities such as head-on, angle, left-turn, and right-turn crashes.
To combat this problem, NCDOT has shined a light on an often overlooked and underutilized safety strategy, All-Way Stop (AWS) control. The agency created a program to implement the treatment in rural, high-speed locations with treatable patterns of injury crashes. AWS is not a new or particularly flashy form of intersection control, but what is innovative is North Carolina’s systemic, widespread application of AWS as a safety strategy for high-risk rural intersections. Beginning in 2020, NCDOT magnified usage of the countermeasure to better influence safety trends. As of early 2023, roughly 450 AWS conversions have been funded as safety projects in North Carolina. Many of these projects have already been implemented and more are underway across the state.
Evaluation data has been compiled for all intersections converted from minor road stop control to AWS through Fall 2022. The results have shown a 92 percent reduction in fatal and serious-injury crashes. Before AWS, there were 81 fatal crashes at the intersections studied. After AWS, there have been no fatal crashes at the study intersections to date. AWS conversions have yielded a benefit cost ratio of 83:1, despite rising construction costs in recent years. The average AWS currently costs roughly $30,000 for the installation of new signing and markings. The average traffic signal project costs six times an AWS project. AWS conversions can thus be implemented at many more locations – and can often be completed in just one day.
Based on the strong safety outcomes already realized, NCDOT plans to continue installing AWS, providing a low-cost high safety benefit for North Carolina’s rural communities and all who travel through them.
Additional Information
Roadway Safety Foundation Executive Director Bruce Hamilton announces North Carolina's Roadway Safety Award.