The in basket: Harry Mock e-mailed to say, “I have noticed that there is a recent change to the traffic light at the Jackson/Lund intersection (in Port Orchard) which is marked by a sign saying “Signal Revision”.  

“Specifically, the left turn lane arrows off of Lund and onto Jackson (both directions) blink yellow at times and, at other times, operate normally (green, yellow red).  Considering the volume of traffic at that intersection, it seems dangerous to have a blinking yellow turn arrow at any time. Can you say what caused this revision?”

The out basket: Kitsap County is putting these signals all over the county. Mile Hill Drive got them last year, and they are in Silverdale, too. North Kitsap has yet to get its first one, though.

The blinking yellow means the same thing as a sign saying “left turn must yield” when facing a green ball signal. They apply to intersections with “permissive” left turns rather than the “protected” left turn where a red arrow disallows turning against it and a green arrow means no oncoming traffic may proceed

Jeff Shea, the county’s traffic engineer says, “The flashing yellow arrow safely increases capacity for signalized intersections. The concept of a permissive turn has always been around with a green ball indication. The green ball  is sometimes misunderstood by motorists, thinking they have the right-of-way to turn in front of oncoming traffic. It gets even more complicated when the signal changes from a left-turn arrow (protected left turn granting right-of-way) to a green ball (permissive left turn – you must yield).  

 “The flashing yellow arrow is better understood by motorists, according to studies,” Jeff said. “We can program them to eliminate the permissive turn if traffic volumes warrant.  

“A major complaint from motorists is having to wait at signals for a green arrow when no oncoming traffic is present,” he said. “The limited application of flashing yellow arrows has been well-received by area motorists. No accidents have been reported where the signal has been installed, and  queues in the left turn lanes have been eliminated or decreased.”

Dave Dahlke read this column on the Road Warrior blog and commented, “I wonder if this is being enacted all of the state or is this only a Kitsap County action.”

I haven’t asked that specifically, but Don Anders, head of the Olympic Region signal shop, says he likes the flashing yellows. “I feel this gives the public a better indication of a caution or yield movement,” he said.  Federal highway officials have allowed “this display to be used on a trail basis and many agencies are putting these into use,” he continued. “Some older signal controllers will not do this flashing operation without some modifications, so many agencies will not use it until they can upgrade equipment.  WSDOT has approval to use this type of display, but we have not used it here in the Olympic Region.”