Reductions in total crashes of 20 percent and 44 percent were found in Davenport and Council Bluffs, respectively. Additionally, while there has been some concern expressed by the public that use of red light running cameras increase rear-end crashes, the Iowa study did not find an increase in rear-end crashes.
In Clive, the effectiveness of the red light running program was evaluated by comparing the number of red light running violations at intersections where cameras were in use versus control intersections where no cameras were present. The researchers found that intersection approaches without cameras had 25 times more red light running violations than intersection approaches with red light running cameras.
Another evaluation conducted in Clive was to measure the amount of time between the point the light turned red and the time drivers continued to enter the intersection. It was expected that most red light running occurs when drivers enter the intersection just at the beginning of the red phase. However, 22 percent of left-turning vehicles, and more than 10 percent of vehicles that were traveling straight through the intersection, ran the red light two or more seconds into the red.
The completed report can be found on the CTRE Web site.
