It's a safety measure! It's a crime deterrent! No, it’s just a design thing.

That’s the case for the blue lights you may have noticed on some of Dallas’ streetlights. David Smith, 56, of Irving said he’s seen these topping the new streetlights near the Trinity River. It led him to ask: Why do the new streetlights on Dallas freeways have a blue LED light on top?

Smith's question is part of Curious Texas, an ongoing project from The Dallas Morning News, which invites you to join our reporting process. The idea is simple: You have questions, and our journalists are trained to track down answers.

This question was simple enough, but finding a Dallas city official who could answer it? Not so easy.

Dallas isn't the only city that has placed blue lights along roadways. They are installed throughout Glasgow, Scotland, and placed at the end of train platforms in Yokohama, Japan. There have been a few vague claims that the lights have led to a decrease in crime in Glasgow and suicide in Yokohama. But those assertions are tough to prove.

As for our blue lights, Corbin Rubinson, public affairs officer for the City of Dallas, was able to track down the answer. Dallas’ blue lights are simply an aesthetic choice as part the Trinity River Corridor Project.

Blue LEDs sit atop the streetlights around the Trinity River at the Ronald Kirk Pedestrian Bridge in downtown Dallas. (Louis DeLuca / Staff Photographer)

Rubinson said the project’s color scheme was blue, green and white, so the blue lights were intended to match that scheme.

“It wasn’t supposed to mean anything substantial,” Rubinson said. “They wanted to implement the brand across all of those properties, and that was a way to do it ... something that makes you think, ‘This is the Trinity.’ ”

According to the Trinity River Corridor Project's design guidelines, the lighting was "envisioned to provide a stimulating and legible nighttime landscape." It also states all of the lights should transform the area into a "cohesive and pleasurable experience for visitors and residents both day and night."

“The intent was to brand the corridor from Royal to the Trinity to Dowdy Ferry,” said Sarah Standifer, the director of Trinity Watershed Management.

Standifer could not give an exact count of the number of blue lights in Dallas, but she said their presence may expand in Dallas and possibly migrate to Irving.

“I heard the City of Irving asked if they could use the same look,” Standifer said. “As improvements are made, you will begin to see more of this type of light.”

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