11/1/07

Red Light Running

Red-light running cameras are all the rage at the moment. Local officials want to install them to reduce red-light running, and we applaud them for seeking to make our intersections safer. The question is, though, is that the best way to make them safer?

Studies have shown that rear-end collisions increase when cameras are installed, so the overall accidents increase. It definitely can be argued that rear-end collisions are not as dangerous as T-bone collisions, but they are still collisions. Engineers should be doing everything they can to avoid them. If every alternative has been exhausted and the only choice is to choose one type over another, then the discussion can turn to which type is less dangerous. Until then, we want to see fewer accidents. Period.

The problem here is that politicians are making the decision by looking at things from an economic perspective. Since red light cameras promise to pay for themselves and then some, it's an easy decision. Cameras come first before other more expensive methods.

What are those expensive methods that help reduce red-light running? For starters, how about retiming signals? Synchronization with the rest of the signal network has the benefit of improving traffic flow in addition to reducing red-light running. Adding a second or two to the yellow has also been shown to reduce collisions. The FHWA offers some more ideas to improve safety here.

There are even newer ideas being put forth to reduce the rate of red-light running. One was presented in the August 2007 issue of the ITE Journal, and the basic premise was to paint the message “Signal Ahead” on the pavement at a precise point before the signal. It would be measured based on the yellow timing and the speed limit so that drivers could know that if the light turned yellow while they were in front of it, they had time to stop safely. If the light turned yellow once they had passed it, they had time to get through the light before it turned red. The article, available without figures here, showed that the rate of red-light running could be reduced 65% with this pavement message.

Painting a pavement message is fairly cheap and retiming signals that need them anyway is also a wise investment. But since cameras actually generate income, they have become the first choice. We can only hope the camera contractors don't work to reduce the yellow signal length like some have been accused of doing, and we can thank our legislature for keeping these off of state roads until better solutions have been tried. We can also ask for better solutions.

3 Comments:

axon said...

You missed put on important way to reduce collisions. How about changing the whole culture of Miami drivers and installing the values that you should be paying attention to the car in front to see if it has stopped. Admittedly this is a long term programme and not easy but it needs to be started at some point. That said, the road painting idea seems worth it.

CL Jahn said...

The problem isn't the timing of the signals, or putting in cameras, or adding signs warning that there's a light.
The problem is that people don't respect the traffic laws, particularly stop lights and intersections. Why do rear end collisions rise? Because the assholes doing the colliding expect everyone to have the same rampant disregard for the law as they do.

These lawless jerks who rear-end the people stopping for the red lights shouldn't be on the road at all.
By all means, fix the timing on the lights, forget the stupid "traffic light ahead sign", and put in cameras.

And start yanking driver's licenses. Get the worst offenders off the road, and you'll REALLY get fewer accidents.

serial catowner said...

After a woman pulled out from a stop sign and ran directly into the side of my car, I learned from my insurance agent that the only time the insurance industry will consider you blameless is when you are rear-ended.

Maybe the insurance people don't want you running red lights to get away from the driver behind you.