Effectiveness of Seasonal Deer Advisories on Changeable Message Signs as a Deer Crash Mitigation Tool

The Virginia Department of Transportation began posting deer advisory messages on changeable message signs (CMSs) along a 16.7-mi segment of Interstate 64 in October 2015. The posting of these messages during the peak of deer activity, from October to November from 5 p.m. to 9 a.m., was intended to raise driver awareness and reduce the high number of deer–vehicle collisions (DVCs) in the area. The effectiveness of deer advisory messages with regard to DVC reduction is not well known. Effectiveness in this study was determined by evaluating deer carcass removal data from three October and November deer advisory posting periods. Vehicle speed evaluations were also conducted to determine whether drivers reduced speed in response to the advisories. Carcass removals were lower when the deer advisories were posted than when they were not posted, and this difference was statistically significant. During the deer advisory postings, there were statistically significant speed reductions of up to 2.8 mph at four of the five vehicle sensor stations. Speed reductions were greater when deer advisories were posted during periods of lower traffic volumes. Seasonal deer advisory messages on an interstate appear to be an effective form of DVC mitigation. Posting seasonal deer advisories every other day on the five existing CMSs in this study’s project area is expected to save approximately $700,000 to $1.4 million over the service life of the CMSs.

Effects of Full Matrix Color Changeable Message Signs on Legibility and Roadway Hazard Visibility

Transportation agencies are considering public–private partnerships as they struggle to fund infrastructure and operations improvements. The national Manual on Uniform Traffic Control Devices (MUTCD) allows acknowledgments of private sponsors on static signs. The legibility and visibility impacts of including logos of sponsors on changeable message signs (CMSs) were examined. Thirty drivers participated in a closed-course study during daytime and nighttime conditions. Full-sized full matrix color LED signs were used to display travel time and safety reminder messages with and without sponsor acknowledgment logos. Single- and dual-phase messages were tested. The measures of effectiveness were legibility distance for target words on the signs and roadway hazard object detection distance. Legibility distances of the CMS messages were notably greater than those of retroreflective traffic signs and well above the MUTCD threshold of 30 ft/in. During the day, the median legibility index was approximately 60 ft/in. At night, the index was approximately 45 ft/in. Sponsor logos had no significant effect on the legibility distances of travel time signs. Sponsor logos had a small effect on the legibility distance of safety message signs with a blue background but not on those with a black background. The use of sponsor logos marginally affected object detection for certain object locations. The results of this study, coupled with an earlier driving simulation evaluation showing no cognitive distraction due to logos, support the use of sponsorship acknowledgment signs on CMSs. An open road evaluation is planned before statewide implementation is enabled.