You’re approaching an intersection late at night, and you’re the only car on the road for a half mile around. What happens? The traffic light turns red just before you get there, because the purportedly “sophisticated” traffic control system is too dumb to sense what is obvious to the eye: No one is coming the other way. The signal blindly shuttles through its motions no matter what the external situation. So you sit idling in the empty intersection, your engine wasting gasoline and spewing exhaust, while the green lights glow magnanimously toward cross traffic that isn’t there.
|It's one AM, there's not a car|
within ten blocks, and this is the signal
you're given at the intersection.
Think about this for a moment: If computers, cars, or coffee makers worked as poorly as America’s traffic signals do, their makers would promptly be laughed off the market. Not so with traffic signals. Despite being quite probably the most inept mechanisms in common use today, signals continue to proliferate, thanks to the many traffic engineers who accept abysmal performance as the norm.
Mind you, your taxes have paid for those signals just as surely as you’ve paid for your car or your computer. What you’re getting for this investment--typically on the order of $80,000-$100,000 or more per intersection, depending on the bells and whistles, is a level of technology that barely qualifies as twentieth century, let alone twenty-first.
But don’t take my word for it. Even so gentle a critic as the Institute of Transportation Engineers--hardly opponents of signaldom--concedes:
“There are about 300,000 traffic signals in the United States alone and over 75% of them could be improved by updating equipment or adjusting the timing.”
This admission is a marvel of understatement, but it certainly accounts for the signal in my late-night example. That just leaves those other 225,000 poorly functioning signals across the nation, many of them no doubt in your town.
This is a traffic signal in Washington, DC in 1926.
Almost a century later, traffic signals still use
essentially the same technology this one did.
The fact that traffic signals need improvement has been obvious for almost a century now, yet in all that time practically nothing of consequence has been done about it. America’s first traffic signal was installed in Cleveland, Ohio in 1914; it used the illuminated words “STOP” and “MOVE”. Around 1920, a Detroit policeman named William Potts came up with the familiar red/yellow/green signal. Since that time, there’s been no fundamental improvement in the way signals work--only more of them to contend with.
Actually, the very earliest signals probably worked better than most modern ones--they were operated by a man in a sort of elevated phone booth overlooking the intersection. He decided who came and went based on the traffic flow from moment to moment--something modern, so-called automated signals still seem utterly incapable of pulling off. Despite the wonders that computers have wrought all around us, and even though coordinating traffic flow would seem the perfect task for a computer, this aim has apparently flummoxed the traffic signal industry. Their products remain nearly as dumb as ever.
But the real point is not that traffic signals need improvement--we’ve known that for nearly a century. Rather, we should take a closer look at what exactly signals do for us, and whether we need so many of them in the first place. We’ll do just that next time, and the answers might surprise you.