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Traffic Watchers And First Responders Work Deep Inside Hanging Lake Tunnel

You’ve most likely driven through the Hanging Lake Tunnel on Interstate 70 near Glenwood Springs. You’ve probably never noticed a giant hanger door or at least paid it no mind. Just behind that door sits a full-time fire and rescue department and one of the most technologically advanced traffic command centers in the state.

There’s a lot of action going on in the 4,000 foot tunnel situated next to the Colorado River, much of it you’d never get a chance to see – until now that is.

Completed in 1992 as part of a massive project to construct I-70 through beautiful Glenwood Canyon, Hanging Lake is a unique tunnel that travels through two rock faces with a Colorado Department of Transportation complex right in the middle. Since the tunnel is seamless, drivers never know they’re moving through – or under – several different areas.


The maintenance bay and I-70 are on the first level of the tunnel complex. The second houses storage, accommodations and the tunnel’s giant fans. The third, a conference room and the heart of the tunnel: The traffic control room.

32 employees maintain the tunnel 24/7, keeping a watchful eye on everything that happens inside and outside the bores. While their first responsibility is to maintain Hanging Lake, should there be an accident anywhere in the canyon they’re the first to respond.

“We are unique inside of CDOT, we train to the brigade level of firefighting. What we’re capable of doing is responding to fires inside of our tunnel, car fires just outside of the tunnel. First responders. We’re there to offer assistance anyway we can,” said Spencer Dickey, the tunnel’s operations manager.

Credit Jim Hill
Fire gear sits at the ready inside Hanging Lake Tunnel's maintenance bay.

Built into the rock outcroppings in Glenwood Canyon is a full-on fire department, complete with a shiny fire truck painted CDOT orange and “Hanging Lake Tunnel Glenwood Canyon,” stenciled on its side.

Each day multiple training sessions are done with air breathing equipment, so if the unthinkable happens, the crew can safely protect drivers and themselves. To keep the crew on their toes, Dickey said he hides trinkets around the tunnel for crews to find while fire training.

“When we do our bunker drills, we dress up in all our firefighting gear and start breathing air and we’ll go and hunt for ‘the penny,’" said Dickey. "The penny has been hidden here for at least 15 years. And it’s someplace nearby that everybody walks past on a daily basis but it has never moved, and there’s only a person or two that knows where it’s at. I know where the penny is, and I check on it from time to time.”

Inside the tunnel, fire suppression water pipes every 150 feet allow the team to battle a blaze directly without trucking water into the tunnel. The water comes from Cinnamon Creek, which has been diverted and now flows underneath the tunnel. In addition to the pipes, massive fans that normally provide air to the tunnel, each moving 250,000 cubic feet of air a minute, can evacuate air quickly though massive vents during an emergency.

“The reason we would do that? Let’s say there was a car fire, the tunnel ceiling is designed to fall away. So when it reaches a certain temperature those panels will drop out of the way,” said Dickey.

The heat would then travel into open space above the tunnel’s false ceiling as the fans force the heat outside and away from people.

It’s just a part of the complex inner-workings of Hanging Lake, all of which are managed from the heart of the tunnel, the command center.

Credit Jim Hill / KUNC
The Hanging Lake Tunnel Traffic Control Center

Situated on the top floor of the complex, next to a surprising set of windows that afford a view outside to the canyon, the traffic control room’s massive screens show dozens of CDOT cameras located throughout the canyon and the tunnel.

Sitting behind a console on this particular day is Control Room Operator Chris McDonald. He darts his eyes between camera shots looking for something very specific, brake lights and directional flashers.

“I monitor 52 live video feed cameras for a 13 mile stretch in Glenwood Canyon. Our objective is to keep traffic flowing and keep the traveling public flowing,” McDonald said. “As you can see, there’s not a whole lot of shoulder along Glenwood Canyon. If we have a vehicle that has an accident, or a flat tire, or is disabled, it’s our job to respond to it as quickly as possible.”

During the day, monitoring the constantly changing live feeds seems a daunting task; however at night McDonald said it’s even worse.

“Because the wall is black, and the only things that you see are headlights or taillights. You learn to pick up on certain things. You know the certain trouble areas that we have in the canyons where we have frequent accidents or disabled vehicles,” McDonald said.

All of the crew wear multiple hats and play a large part in keeping the public safe. The command center is not just for the tunnel, it covers a massive area.

“So not only are we dealing with just our 13 mile stretch, we’re dealing with everybody from the Utah state line all the way to Eisenhower [Tunnel’s] front door,” McDonald said. “So if there’s an accident, a slide off, a spin off, a chain-law, anything that happens on our state highways or interstates comes right through here.”

For good measure you can also throw in responsibility for the Beavertail Mountain Tunnel near Grand Junction and Wolf Creek Pass Tunnel in Southwestern Colorado.

All of this is hidden inside the tunnel and the two rock faces near Hanging Lake. But you can catch a glimpse of it if you stop at the rest area. Operations manager Dickey notes “you can see the ridge line of the complex, if you know where to look.”

Credit Jim Hill / KUNC
CDOT's Hanging Lake Tunnel command center, hidden inside Glenwood Canyon.

A door near the command center opens below an earthen helipad and the roof of the complex, all blended into the landscape. CDOT said one of the main design goals of the tunnel was to camouflage the building into the surrounding environment. From rusted color guardrails to the command center with a grass covered roof, the entire Glenwood Canyon project is intended not to detract from the surrounding beauty.

The crew that works the Hanging Lake Tunnel affectionately refer to it as ‘her.’

“We put a lot of maintenance into this place, just keeping it clean and keeping the facility in top notch shape, you know? When she needs repainting, we repaint it, we wash it all the time, we’re real proud of it,” Operations Manager Dickey said.

So the next time you enter Glenwood Canyon, know that the Hanging Lake Tunnel CDOT crew is there, working tirelessly to maintain their tunnel, and keep you safe.

They’re just fine knowing many will never realize they’re even there.

Explore the map and help us find more of the lost, forgotten or the little-known in the Centennial State. Have an idea? Send us a tip for Hidden Colorado.

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