Evaluating the Safety Performance of Delineator-Based Temporary Restricted Crossing U-Turns as a Cost-Effective Treatment

Restricted Crossing U-turn (RCUT) intersections have proven highly effective at reducing crashes on rural high-speed highways. As a cost-effective interim solution, transportation agencies may implement delineator-based temporary RCUTs before constructing permanent concrete-median installations. However, the safety performance of temporary RCUTs remains underexamined in the current literature. This study evaluates the safety performance of six unsignalized temporary RCUTs in Mississippi: three on urban six-lane divided highways and three on rural four-lane roadways installed between 2015 and 2022. This study considered two before–after safety evaluations: naïve annual crash frequency analysis and a rigorous Empirical Bayes (EB) method. The crash modification factor (CMF) estimation was facilitated by developing new local safety performance functions (SPFs), and the results were compared with those derived from Highway Safety Manual (HSM) SPFs and state-specific SPFs. Results showed that at urban locations, there was a 28% reduction in total crashes and 18% in fatal and injury (FI) crashes. Rural locations showed even more promising results, with a 74% reduction in total crashes and 71% reduction in FI crashes at the intersection-level analysis. These results demonstrate that temporary RCUTs can achieve safety benefits comparable to conventional intersections, particularly in rural, moderate-volume contexts. Given their significantly lower construction cost ($111,000 versus $3.8 million), temporary RCUTs represent one of the most cost-effective solutions for agencies seeking immediate crash reduction at high-risk locations.