The Drive: Crash rate shows many drivers failing to yield on flashing yellow arrow

By the looks of things, drivers in Plymouth — and probably other places, too — could use a crash course on how to navigate intersections governed by flashing yellow turn arrows.

This comes after an analysis by Plymouth police found that nearly 50 percent of crashes at the intersection of Rockford Road and Fernbrook Lane were the result of drivers not yielding to oncoming traffic when flashing yellow arrows were operating.

Between March 10, 2016 and Feb. 22, officer Scott Kirchner said there were 34 crashes at the busy intersection, and 16 were attributed to motorists failing to yield. The intersection handles 21,000 vehicles a day, according to a 2013 traffic count by the Hennepin County Transportation Department. Of those drivers, 4,093 make left turns. Keep in mind those counts were taken four years ago so the numbers are probably higher.

Kirchner has his theories as to why the crash numbers are so high.

Drivers may not be paying attention or maybe are taking risky chances by not allowing enough room between them and oncoming cars. Impatience might be a factor, too. He said drivers waiting to turn at the intersection have had motorists behind them honk.

"They hear that horn and think it's my turn and go without thinking," Kirchner said. "There is the pressure and they think maybe I can make this gap."

Flashing yellow arrows were approved for use in the mid-2000s by the Federal Highway Administration and lately have been showing up in growing numbers as old traffic signals are replaced. At last estimate, the Minnesota Department of Transportation has about 190 flashing yellow arrows on signals it controls in the metro area. Others, such as the ones at Rockford and Fernbrook, were put up by Hennepin County, which has about 93, excluding the city of Minneapolis.

Flashing arrows can keep traffic flowing by moving more vehicles through intersections and eliminating long waits at signals with left-turn arrows, where it can take a long time to complete a cycle. Here is a primer:

Drivers in a left turn lane encountering a solid red arrow must not enter the intersection and stop and wait. They may proceed when they are shown a green arrow, which allows a protected turn, meaning oncoming traffic sees red. Flashing yellow arrows allow motorists to make what's called a permitted turn, meaning the driver must yield to oncoming traffic and pedestrians. It's like having a solid green light, but the yellow is meant to remind motorists to use caution in case oncoming traffic also has a green light.

Signs posted at intersections tell drivers what the flash mode means and the correct course of action to take.

Kirchner summed it up nicely: "Drivers should reduce speed, activate turn signals and evaluate to see if any vehicles or pedestrians are coming before turning," he said. "A flashing yellow doesn't mean you have to make a turn. There is no shame for stopping and waiting until there is a gap or a solid green arrow."

Flashing yellow arrows generally do not operate at peak periods, but Kirchner said a number of the crashes at Fernbrook and Rockford occurred at midday hours. The city has asked county planners to restrict the times when the flashing arrows are on and to disable them when pedestrians push the button to get a walk signal.

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