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Q. I drive U.S. 1 through Wake Forest to and from Franklin County almost every day.

For as long as I can remember the stop light at Wake Union Church Road and U.S. 1 at the Lowes Foods grocery store shopping center is almost always red. The lesser traveled side road (Wake Union Church) has more green light than the heavily traveled U.S. 1. Why?

Thank you,

Philip B. Cook, Raleigh

A. According to Steve Johnson, division traffic engineer for the state Department of Transportation, there is usually substantially more time for the green lights on Capital Boulevard (U.S. 1) than for Wake Union Church Road. However, the wait time may seem longer at that intersection because there are more phases -- a left turn is a phase, for instance -- to serve on both Capital and Wake Union Church than other nearby intersections.

"The more phases that you have, the more time that is taken away from the main street," Johnson said.

In other words, while the green lights on Wake Union Church may seem like they last a long time, the light on Capital is actually green for a longer amount of time.

The actual length of the green light does depend on the time of day. Johnson says in the morning, more traffic is coming southbound on Capital and in the evening the opposite is true.

He said the proximity of the signals on the stretch of Capital near Wake Union Church Road make traffic flow difficult to manage.

"We're trying to coordinate the traffic through there [to keep it moving well]," he said.

Johnson explained that the signal systems that run from Wake Union Church Road to Holden Road in Franklin County are synchronized to allow traffic controllers to coordinate the green lights.

"It's a long stretch along Capital up there," Johnson said. "You'll have to stop somewhere."

Johnson said he will have a signal technician check out the lights at the intersection to make sure they are functioning properly.