Effectiveness of Speed Tables as a Traffic Calming Measure on a College Campus Street

The purpose of this study is to quantify the effectiveness of three speed tables installed on a college campus roadway as a traffic calming measure (TCM), regarding vehicle speeds, volumes, and pedestrian safety. Speed tables with integrated raised pedestrian crosswalks were installed to increase pedestrian safety by (1) increasing the visibility of pedestrians to motorists, (2) slowing vehicles down, and (3) diverting vehicles to alternative routes. This study consists of before-and-after comparisons of vehicular traffic data, which compares traditional crosswalks vis-a-vis speed tables with integrated crosswalks. Analyses include changes in 85th percentile speeds, mean speeds, and standard deviations in speed. Statistical tests were performed to evaluate if changes between ‘before’ and ‘after’ conditions were statistically significant. Additionally, data were analyzed to determine whether or not the speed tables have a cumulative effect on vehicle speeds due to the close spacing of the TCMs. This research indicates that the 85th percentile and the mean speed decreased 6 mph and 5 mph (9.7 km/h and 8.1 km/h), respectively. The change in speed was concentrated in the high to mid range speeds with low speeds being the least affected. Additionally, a cumulative effect was observed for the mean speed, but not the 85th percentile speed.