Red means stop, green means go, blue means — wait, what?

Drivers on 23rd St. after Wednesday morning might be surprised to see blue traffic lights when they cross Louisiana and Iowa streets. The blue lights don’t signal some new traffic rule; they’re meant to help enforce an old standard: stopping at the red light.

City workers and researchers from the Kansas University School of Engineering are partnering to install eight blue lights Wednesday at the intersections of 23rd and Louisiana and 23rd and Iowa streets as part of an experimental traffic safety effort.

Drivers don’t need to do anything different when they see the blue lights perched at the four points of each intersection, said Steven Schrock, one of the leaders of the research group and an assistant professor at KU’s Department of Civil, Environmental and Architectural Engineering.

The blue light simply turns on when the existing traffic light turns red, allowing police to see from any direction whether a driver just made it through on yellow or blew the red light long after it turned.

Ordinarily, a police officer can only be sure of a red light violation if positioned directly behind the driver. The researchers see the blue lights as an alternative to automated red-light cameras, which are used to catch offending motorists in other states but are not allowed in Kansas.

Transportation officials say the human cost of ignoring red lights is significant. At least 676 people across the nation died in vehicle accidents in 2009, the most recent year for which national figures are available, because a driver ran a red light, according to the Federal Highway Administration. The project in Lawrence, and a twin version in Overland Park at the intersections of College Boulevard and South Quivira Rd, and W. 75th Street and Metcalf Ave., is being paid for with a $120,000 grant from the Kansas Department of Transportation and the Mid-America Transportation Center, a consortium of university research centers from across the Midwest.

The study group, also led by Eric Fitzsimmons, a researcher at the KU Transportation Research Institute, watched video of about a dozen intersections in Lawrence and consulted with city officials and police before settling on the intersections at Louisiana and Iowa Street. Those two were chosen because they handle a high volume of traffic and showed a persistent pattern of drivers running red lights.

The Lawrence Police Department did not seek out this this project in order to write more tickets, according to Sgt. Trent McKinley, a Lawrence Police Department spokesman. But officers will find it helpful in making sure the tickets they do write pass muster in court, and the blue lights will allow them to watch for red-light runners more safely, without having to position themselves in the middle of traffic.

Over the next six months, the KU researchers will continue studying all of those intersections — with and without blue lights — and report to city and state officials any differences they find.

Similar blue lights have been tried in Florida, Kentucky, Texas and Minnesota, but there hasn’t been enough data collected to say for sure how well they work, Schrock said. For their part, city officials in Naples, Fla., where the blue lights were installed earlier this year, say it isn’t clear what effect they have had on driver behavior.

The researchers hope the blue lights will affect driver behavior across a wider area than the two intersections, but say they won’t know until they see how people respond. People might tend to run red lights at a certain intersections because the timing of the signals makes the wait seem longer than it is, Schrock said, or because it is a difficult place for police to catch them.

“If people seem to get the perception that ‘I could cheat here,’ or ‘I can see that people are cheating here and not getting caught,’ then the power of the red light to stop people is less,” Schrock said. “But, if word gets out about the blue lights, maybe they’ll say ‘Not at this intersection.'”