TRAFFIC SIGNALS: Utah DOT traffic software cuts chances of hitting red light to 28%

Department no longer relies on driver feedback

December 23, 2013

Utah DOT’s (UDOT’s) traffic-analyzing software, paired with highway traffic sensors, has allowed the state to reduce red lights’ effect on traffic. Using the software, UDOT adjusted traffic lights and made it so an average of 28% of traffic hits a red light at a given highway intersection.

Before the system, UDOT relied on direct feedback from drivers and in-person studies to measure the effectiveness of intersection traffic management. The new system utilizes radar units, video units and electromagnetic loops in the pavement, which automatically send UDOT information on how many cars hit red or green lights and how fast they approach the intersection.

According to system data, Bangerter Highway and 4100 South has the worst red light rate in November, with 82% of traffic stopping at the intersection. The best intersection for the month was at the I-15 northbound ramp and 12th street in Ogden, where no cars encountered a red light.

UDOT will continue to use the software to improve traffic light management. Meanwhile, other states are looking into copying the system for their own use.