The city of O’Fallon’s new Flashing Yellow Arrow Signalization Project officially kicked off with the installation of “flashing yellow arrow” signal heads at 28 intersections throughout the city, including already completed additions along the Hwy. K corridor, which were installed by the Missouri Department of Transportation.
The project is part of an ongoing effort to improve safety for left-turning drivers. Usually, when turning left, a protected-only left turn traffic signal with a green arrow is used; however, the use of protected-only left turns reduces the overall capacity for traffic flow through an intersection.
Implementing green arrows and flashing yellow signalization has been cited by O’Fallon city staff as a way to increase left-turn capacity while allowing for the safe flow of oncoming traffic. A flashing yellow left-turn arrow means that left turns are only permitted after drivers first yield to oncoming traffic and pedestrians before proceeding with caution. Drivers will be prompted to wait for a safe gap in oncoming traffic and in pedestrian flow from sidewalks before turning.
For the project, O’Fallon has contracted by local company Gerstner Electric for the installation of the new signal heads. Work already has begun in the city and will continue throughout the next few months.