Evaluating Drivers Stop Line Violation Behavior At Signalized Intersections

Stop lines are common at intersections; however, few studies have focused on the position of stopped vehicles with respect to the stop line. Often drivers will stop their vehicles over the line creating potential operational or safety problems. In this thesis, data collected from local intersections in State College, Pennsylvania, indicated that only 61 percent of the vehicles observed were in compliance and 13 percent of the vehicles observed were committing severe violations. The data were analyzed to characterize driver behavior related to stop location during red phases. Driver stop line violations were influenced by many factors in this study. Lane usage (right turn only) was associated with high violation rates. Minor roads, when compared to major roads, were more likely to have more severe violations, while morning periods had more minor violations than other time periods. Through only lanes or increased distance from the stop line to the crosswalk or curb extension line promoted higher rates of compliance. Improvements on having a good sight view, keeping enough sight distance and vehicle stop distance could be good choices on reducing severe stop line violations. Increasing the distance from a stop line to a crosswalk or curb extension line an additional 10 feet might provide enough space for the majority of the vehicles stopping at an intersection from entering the crosswalk or intersection area.