Tuesday, June 18 2013, 10:14 AM MDT
Good Question: Freeway Sign Times
By Matt Gephardt
Edited by Ryan Malavolta
Photography by Brian Morris
(KUTV) This question comes from a viewer named Stefanie. Stefanie says she drives from Lehi to Downtown Salt Lake City every day and she relies on freeway signs that tell her how long it will take. She says they are always dead on and she wants to know how they do it.
As freeway travelers know there is a tool to help you know when you will get to where you're going. There are several signs along the Wasatch Front usually displaying the minutes it will take to get someplace.
Glenn Wlackwelder, the Traffic Operations Engineer for the Utah Department of Transportation says the accuracy of those signs starts with radar technology. UDOT has attached radar units to freeway poles every half mile from Ogden to Provo. The radars gather freeway speeds and that data is sent to UDOT's traffic operations center. A computer does the math and tells controllers in the center what each sign should read.
It's convenient for drivers, but Glenn says the signs serve a greater purpose: keeping drivers safe.
"We use them to warn about incidents," he said.
The messages in the signs can be changed to warn about an accident ahead, upcoming construction, poor weather conditions or anything else that might pose a hazard to drivers. Glenn says studies have shown that when drivers are warned about danger ahead they are more alert and there are fewer secondary crashes.
Editor’s note: Thanks Stefanie for the Good Question. If you a good question email Matt at Gephardt@kutv.tv
(Copyright 2013 Sinclair Broadcasting Group)