The two intersections near my office have traffic lights that are unlike any others I’ve seen, and I fear that they are confusing to drivers and therefore dangerous.
On the north and south sides of the intersection there are three lanes: a left turn lane, a through lane, and a right turn lane. On the east and west sides, there are four lanes (two through lanes). All four sides of the intersection have the normal red/yellow/green through lights and a left turn light.
A traditional traffic light is green, turns yellow for a short period, and then turns red. They have been this way for decades–certainly for the 40+ years I’ve been aware of the way that traffic lights work. Left turn lights work much the same way. The left turn arrow might work on a different schedule than the through lights, but it traditionally follows the green to yellow to red pattern. Or, it might have only green and off, meaning that you have to yield to oncoming traffic when the light is off, but the oncoming traffic has a red light when the left turn light is green.
The left turn lights at this intersection are different. And confusing. They blink yellow to mean, “You may turn after yielding to oncoming traffic.” After the blinking yellow period, they turn green. So drivers have to know that solid yellow means “red is soon to come,” but blinking yellow means, “green is soon to come.”
It doesn’t help, of course, that years of experience have taught drivers that in practice a yellow left turn signal means, “Hurry up through the intersection before the light turns red.”
Every day I see drivers not fully understanding what that blinking yellow means. Some, when they see the blinking yellow, dash through the intersection heedless of oncoming traffic. I can only conclude that they don’t understand that the rules have changed and a light might start blinking yellow. Other drivers see the blinking yellow and hesitate when it’s clear that there is no oncoming traffic and they’re fully within their rights to proceed.
I realize that blinking yellow means “proceed with caution.” But traditionally that’s done with all of the lanes at an intersection (going the same way, of course). But drivers aren’t accustomed to seeing blinking yellow on one light, and solid red or green on the other lights. And they’re certainly not prepared for a blinking yellow light to suddenly go green.
I’ll grant that I’ve only seen two crashes (after the fact–I wasn’t present for the actual impact) at these intersections in the three months I’ve been here. But I’ve seen too many close calls to believe that this unorthodox use of the signal lights is a good idea. I can only hope that those in charge of the traffic lights will see this dangerous situation for what it is and reprogram the lights back to something more reasonable.