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Old 2007-07-10
Red Light Ray
Posts: n/a
Smile RLC technology

I read your blog regarding red light cameras, Veil Guy. I'm surprised Philly took so long to implement them. I was at the Int'l Assn. of Chiefs of Police conference which, coincidentally, was in Philly in 2003. And on a city street outside the convention center they had an ATS demo system installed. Looked just like your photos.

You asked whether any city has tried engineering solutions to red light running. Good question, being that rampant red light running is always caused by a) roads that are out of capacity, b) yellow lights timed too short or usually, both.

I did an analysis in 2004 of Mesa, Arizona's RLC system and found that by putting RLCs at problem intersections, all they did was increase accidents. Mostly rear-end collisions, the rate increased by an average of 30% at every RLC intersection. (Many of the intersections weren't "problems" with lots of accidents, they were just high-volume.)

To their credit, the city transportation engineers finally lengthened the yellow by one second at an intersection with the most left-turn accidents. Presto. The problem disappeared. Accidents dropped 78% overnight. And stayed there.

They did likewise at the second most troublesome intersection, also a double-left-turn situation, with similar results.

Then they got sued by Lockheed-Martin (now Affiliated Computer Systems), the RLC vendor, because with no more violations, fines (income) dropped to nothing and failed to meet the minimum stiuplated in the contract. So they moved the cameras to a more lucrative location. But the accidents didn't recur.

My mother recently sent me a news clip from Ft. collins, CO where they live, another ATS account but with only one RLC. Last time I was up there I timed the yellow at that intersection. It was 1.5 seconds too short, based on my calculations. So now they've added a second camera. Revenue goes up and the city-engineered problem remains. Smart thinking.
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