Safety Evaluation of Roundabouts and Speed Cameras Within the City of Ottawa

To improve traffic safety, governments must efficiently utilize funds by selecting the most effective treatments in specific local conditions. This thesis provides a framework to evaluate the safety effectiveness of roundabouts and speed cameras as two new safety treatments in the City of Ottawa. The study uses collision history and driving behaviour analysis to capture the impacts of different safety improvement tools. The roundabouts collision history-based results revealed a slight increase in total, rear-end, SMV and PDO collisions, a substantial increase in sideswipe collisions, and a reduction in angle and injury-fatal collisions. The driving behaviour at the roundabouts merging zone showed the average post-encroachment above 2 seconds which is more than saturation headway and it is an acceptable value. The speed cameras driving behaviour analysis indicated a reduction in speed and a number of vehicles exceeding the speed limit from downstream of speed cameras to upstream.