AASHTO Journal - Colorado DOT Finishing I-70 West Vail Pass Project

The Colorado Department of Transportation is preparing to kick off the final construction season for the I-70 West Vail Pass Auxiliary Lane Project this month, with full project completion expected by the end of 2026.

[Above photo by Colorado DOT]

The project, which began in 2021, aims to improve safety and operations on West Vail Pass by enhancing a 10-mile stretch of I-70 between the East Vail Interchange (Mile Point 180) and the Vail Pass Rest Area (MP 190).

Colorado DOT noted that its crews will focus on remaining roadway and paving operations, finish wildlife crossing construction, and install avalanche and rockfall mitigation infrastructure. Work will also include landscaping and final improvements to the recreation path beneath the new bridges, the agency said.

“As we enter the final season of this critical project, our focus is on a safe and successful project completion,” noted Shoshana Lew, Colorado DOT’s executive director, in a statement.

“From new bridges and pavement to wildlife crossings and avalanche and rockfall mitigation, every element of this work will make Vail Pass more resilient, reduce crashes and closures, and provide a more reliable and enjoyable trip for everyone traveling the I-70 Mountain Corridor,” she said.

Specifically, Colorado DOT aims to complete the project’s six wildlife underpasses this year — two for large animals and four for small to medium-sized animals.

The project also includes new avalanche and rockfall mitigation infrastructure in the area known as The Narrows around mile post 186. This system — the first of its kind in the state — will enable Colorado DOT and the Colorado Avalanche Information Center to safely monitor and manage a known avalanche path, reducing the likelihood of extended interstate closures. Installation work will require rock scaling and helicopter operations, resulting in periodic 20-minute traffic holds on I-70 in both directions.

Finally, Colorado DOT said it also recently launched a dedicated resource page for motorists traveling the I-70 Mountain Corridor. This one-stop source provides year-round driving information, real-time road conditions, and safety tips.

It also highlights major corridor improvements — such as I-70 West Vail Pass Auxiliary Lane Project and Floyd Hill — while centralizing the best tools from COtrip.org and the COtrip Planner mobile application, the agency noted.