If you’ve driven through Glenwood Canyon, you know how stunning it is. Towering cliffs, winding roads, the Colorado River rushing below—it’s one of the most iconic stretches of Interstate 70. But starting in mid-July, that view will come with a slowdown.

The Colorado Department of Transportation (CDOT) is launching a long-term construction project to replace bridge joints and make safety upgrades across 23 structures between mile markers 116 and 133. And yes, it’s going to affect traffic.

What’s being fixed—and why it matters

It’s easy to miss them when cruising at highway speeds, but bridge joints are vital. They help bridges flex and expand with temperature swings, heavy traffic, and even seismic activity. When they start failing, things can go south fast.

That’s why CDOT is replacing 23 joints across Glenwood Canyon.

According to agency officials, the targeted structures are aging and need critical reinforcement. Besides joint work, crews will also repair guardrails that have been damaged over the years by crashes, rockslides, and weather.

The full list of impacted exits includes:

• Exit 119 – No Name

• Exit 122 – Grizzly Creek Rest Area

• Exit 123 – Shoshone Power Plant

• Exit 125 – Hanging Lake Trailhead

• Exit 129 – Bair Ranch Rest Area

And while that might not seem like a huge distance on paper, if you’ve ever been stuck behind a semi in the canyon, you know just how long 17 miles can feel.

Lane closures, speed drops, and two years of disruptions

CDOT says travelers should brace for some changes.

Starting in mid-July, one-lane closures will begin in each direction. Speed limits will also be reduced to 35 mph through the work zones—a big drop from the usual 50 to 65 mph range in certain areas.

Here’s what else to expect:

• Work hours: 7 a.m. to 7 p.m., Monday through Friday

• Traffic pattern changes: Lane shifts and merging in tight spots

• Rest area access: May be limited at times due to nearby activity

• Speed enforcement: Yes, there will be patrols

And for the planners out there: yes, there will be a winter shutdown if snow and ice become an issue. Construction will pause when conditions make the work unsafe or inefficient.

Not just maintenance—it’s part of a bigger puzzle

At first glance, $7.5 million might sound like a lot for joint replacement and guardrails. But in transportation dollars? It’s fairly modest.

CDOT officials say this project is part of a broader strategy to keep Glenwood Canyon viable for decades. The canyon has faced multiple closures in recent years—some weather-related, others from mudslides, and even some due to wildfires.

Here’s a quick breakdown of related past events:

These incidents revealed just how fragile—and important—this corridor really is. Keeping it functioning means not only protecting infrastructure but also ensuring access for tourism, commerce, and emergency services.

Local businesses already bracing

Along the corridor, especially in Glenwood Springs, there’s a mix of anticipation and frustration. Nobody’s thrilled about lane closures, but many understand it’s necessary.

“I get it,” said Robby Decker, a rafting guide whose company relies on canyon access. “But man, the slowdown’s gonna hurt during peak season.”

Decker isn’t alone. Tourism businesses from hot springs to hiking outfitters rely on smooth traffic. A lot of folks come in from Denver or Grand Junction, and when I-70 backs up, so does business.

Still, the long-term view helps.

“If it means fewer closures down the line, then okay,” Decker added. “We just need folks to be patient.”

What CDOT wants drivers to know

The agency has already started outreach, posting digital signs along I-70 and launching online updates. They’re trying to get ahead of confusion and complaints by pushing transparency now.

“We’re asking folks to plan ahead,” said a CDOT spokesperson. “If you know you’re driving through Glenwood Canyon, give yourself extra time. And stay alert.”

They’re also urging drivers not to rely on navigation apps for canyon detours. Some past closures pushed desperate travelers onto remote forest roads, leading to breakdowns and even rescues.

For now, CDOT hopes communication and preparation will soften the blow of the work.

“We know Glenwood Canyon is special,” the spokesperson said. “We want to keep it that way.”