Safety effectiveness of stop control at ultralow-volume unpaved intersections

Establishment of the proper level of traffic control on low-volume rural roads can be problematic for local agencies. Ten years of crash data for more than 6,000 rural, unpaved intersections in Iowa were analyzed, with stop-controlled intersections compared with uncontrolled intersections. Crash models were developed with logistic regression and hierarchical Poisson estimation. For ultralow-volume intersections, those used by fewer than 150 vehicles per day, results indicated no statistical difference in the safety performance of each level of control. The effect of excessive use of control on safety performance also was tested for rural and urban applications, with no detrimental effect generally being indicated.