Fire suppression system was key for fire crews battling blaze in Eisenhower Tunnel

The Eisenhower-Johnson Memorial Tunnel right at the line between Summit and Clear Creek Counties is now flowing freely with Interstate 70 traffic but still sporting the scorch marks from Monday's van fire. 

Colorado Department of Transportation spokeswoman Tamara Rollison said staff operators saw the fire in one or two of the 75 cameras inside of the tunnel and set off the fire suppression system, installed in 2015 (with a price tag of $20 million).

Firefighters were ultimately the ones who fully extinguished the van and got it out of the way, but that fire suppression system was key in making sure they could get in there in the first place. 

"It keeps the tunnel cool enough," Rollison said. "If you don't have something like that, you have a tunnel, you have a vehicle fire. It can heat up that tunnel really, really fast, making it very difficult for firefighters to do their jobs.

Lane closures for the tunnel will continue to run Sunday through Thursday overnight as the CDOT team upgrades the camera system, and Rollison said it's likely they'll use those closures to help replace the scorched tiles from the fire.