News / Utah / 

Blowing wet snow obscured many traffic lights

By Keith McCord | Posted - Feb. 17, 2011 at 6:14 p.m.


2 photos

This archived news story is available only for your personal, non-commercial use. Information in the story may be outdated or superseded by additional information. Reading or replaying the story in its archived form does not constitute a republication of the story.

SALT LAKE CITY — Winter storms certainly cause headaches for motorists. Blowing and drifting snow, slick pavement and power outages turn traffic signals into four-way stops.

Wednesday night’s storm added another twist where Mother Nature and new technology played a role.

Motorists coming into downtown Salt Lake City using Beck Street Thursday morning encountered a confusing situation at the intersection at 400 North. At first glance, the traffic signals appeared not to be working, perhaps due to a power outage.

Then all of the sudden, the green lights illuminated as normal.

Actually, the lights worked fine. But heavy, wet snow, driven by the high winds overnight had packed onto the red and yellow tubes on the signals, completely obscuring them. Motorists approaching the intersection weren’t really sure if they should proceed or not.


We see that occasionally, the conditions have to be just so ... a perfect storm. If it's dry powdery snow, it doesn't stick to the signals, so it's the combination of very strong winds, wet snow that's blowing directly into the signal.

–Dave Kinnecom


"We see that occasionally, the conditions have to be just so ... a perfect storm," said Dave Kinnecom, traffic operations engineer for the Utah Department of Transportation. “If it's dry powdery snow, it doesn't stick to the signals, so it's the combination of very strong winds, wet snow that's blowing directly into the signal."

Not only were motorists affected, but pedestrians too. Several of the “Walk/”Don’t Walk” signals at intersections in downtown Salt Lake City were covered with snow and ice Thursday, leaving people to guess whether it was their turn to cross the street.

Because of the safety issue, motorists are urged to report any problems with traffic signals. Kinnecom said a handful of calls from motorists in the Salt Lake and Ogden areas came in. When calls come in about an improperly working traffic signal, crews are dispatched as soon as possible.

Besides the precise direction of the blowing snow, the lights themselves played a role in this, too. All traffic signals now use the energy-efficient LEDs. Kinnecom said that creates a bit of a trade-off in situations like this.

"The LED signals use about one-twentieth of the electricity of the old incandescent bulbs”, he said. “Those incandescent bulbs generated heat, which would melt the snow. The LEDs don't generate any heat."

Most states now use LEDs for traffic signals. They last a lot longer, and are much more economical. “They do save UDOT hundreds of thousands of dollars every year,” he said.

E-mail: kmccord@ksl.com

Photos

Related Stories

Keith McCord

    SIGN UP FOR THE KSL.COM NEWSLETTER

    Catch up on the top news and features from KSL.com, sent weekly.
    By subscribing, you acknowledge and agree to KSL.com's Terms of Use and Privacy Policy.

    KSL Weather Forecast