New left-turn signals pop up through the Metroplex

Yellow flashing arrows are all the rage here in North Texas. The new addition to left-turn signals has been popping up in cities such as Grapevine, Frisco and Arlington, and may soon be coming to busy intersections near you.

Implementation of the new signals is a result of changes to the 2009 Manual on Uniform Traffic Control Devices made effective in January 2010.

States were given a two-year period from the effective date to either adopt the MUTCD or have a State MUTCD/supplement that is in substantial conformance with the national version.

Texas adopted a State MUTCD in December of last year, prompting cities to begin the implementation of the new system if they had not already done so.

Researchers and policymakers cite a number of reasons for the change.

Safety improvements

Transportation experts say the new system will help keep drivers safe, encouraging them to proceed with caution while turning left at a time when they would traditionally be seeing a solid green light.

Research has show that the new configuration also helps to eliminate accidents caused by left-turning drivers who cut across an intersection as the lights on their side turn yellow and red because they believe oncoming traffic, too, is coming to a halt.

Traffic flexibility

Traffic engineers say the new signals provide more than increased safety; they provide efficiency.

The addition of the yellow flashing arrow will offer engineers more options to handle variable traffic conditions and provide more opportunities for drivers to turn left during peak traffic times and at busy intersections.

National implementation

A traffic study conducted before implementation of the new system discovered that a lack of detailed direction in the MUTCD had resulted in the development of a variety of left-turn signal systems.

Nationally, four different systems were being used on a regular basis and additional variations from those four could be found as well.

Although officials expect that it may take time for drivers to adapt to the new system, the Federal Highway Administration anticipates that consistency nationwide will help cut down on accidents created by drivers who are unoccustomed to regional variations.

Local timelines

Although other cities in the Dallas-Fort Worth area have already begun swapping their signals, neither city nor Texas Department of Transportation officials have plans to install these signals along major thoroughfares in Colleyville or Southlake yet.

Grapevine's first flashing-yellow-arrow display was switched on last fall at the intersection of Mustang Drive and Stone Myers Parkway.

Additional signals will be considered on a case-by-case basis as the city opens new intersections, including those associated with the DFW Connector, and as equipment already in use requires replacement in the coming years, officials said.