San Antonio residents may notice more flashing yellow arrows at various intersections around the city.
The City’s Department of Public Works completed a 12-month pilot program in October 2009 to operate flashing yellow arrow left-turn signals at 22 intersections. Since its introduction, a total of 163 intersections across the city currently have flashing yellow arrow installations operating and additional intersections are being considered for placements.
A flashing yellow arrow does not replace a solid yellow arrow – a flashing yellow arrow gives drivers extra time to make their turn when it is safe to do so. A solid yellow arrow tells drivers to slow down before a solid red arrow stops them. Drivers can turn left on a flashing yellow arrow as long as they yield to oncoming traffic and pedestrians. Drivers cannot begin a left turn on a solid yellow arrow.
Research on the use of flashing yellow arrow left-turn signals has shown increase intersection efficiency by allowing traffic engineers more flexibility in operating traffic signals based on traffic volume. A seven year study completed by the National Cooperative Highway Research Program on behalf of the Federal Highway Administration found that drivers made fewer mistakes with flashing yellow arrow signals than with traditional left-turn signals.