How does the Road Commission determine when and where to put traffic signals?
A traffic control signal should not be installed unless an engineering study indicates that installing a traffic control signal will improve the overall safety and/or operation of the intersection. The engineering study includes the evaluation of warrants (guidelines) identified in the Michigan Manual of Uniform Traffic Control Devices (MMUTCD). The warrants consider vehicular and pedestrian volumes, crash history, vehicle delay and vehicular progression. Prior to the installation of a traffic control signal, the roadway may need improvements to provide acceptable traffic operations at the intersection. Finally, adequate funding must be available to finance the installation of traffic control signal and any necessary roadway improvements.
