A construction flagger who was directing traffic was hit and killed by an SUV on Wednesday afternoon northwest of Denver, according to the Colorado State Patrol.

Thursday, Colorado State Patrol identified the victim as 51-year-old Sean Keller. He was working on a construction site at 62nd and Lowell Boulevard when the incident happened. Investigators say he had switched his sign to stop but the driver of the jeep didn't. The vehicle hit Keller and pinned him.

“When you’re out on the road don’t take your transportation system for granted,” Tamera Rollison a CDOT spokesperson said. “There’s been a lot of work, a lot of bloodshed to build our roads across the state.”

Rollison is reminded of that daily. Outside her office, there’s a rock with the 60 names of CDOT employees who have died in work zones.

"Each of the workers that you see on this wall they were coming to work thinking they would go back home at the end of the day but they didn't,” she said.  

Like Sean Keller.

"It is a tough time and it is a tough day for all of us when we find that out because we come to work every day to make the roads safer,” Rollison said. “We come to work every day to help save lives and make lives better."

Trooper Gary Cutler said he understands that side of the job.

"A lot of people that it's just law enforcement and firefighters that get hurt on the side of the road and that's not the case,” he said.  

Cutler said he sees people flying through construction zones all the time.

"This is our office,” he said. “This is where we work every day. If you were in an office and you were sitting in your chair and you have a car come by you at 60, 70 miles an hour that would be very unnerving."

He said he wants the driver to put themselves in the boots of construction workers.

"You want them to go home just like you want to get home," Cutler said.

A reminder Rollison said she's happy to see every day.

"It reminds me of what we're here for and it reminds of our workforce who gave their lives to deliver a good transportation system," she said. "I'm thankful for the individuals on this wall and for what they have done."

According to CDOT- our state saw 15 work zone fatalities in 2017. Most of the deaths are people in cars.

CSP said it's still unclear why the Jeep that killed Sean Keller didn't stop and It's too early to say if the person who was driving will be charged.

Keller leaves behind a wife.

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