I-70 West Vail Pass Auxiliary Lanes project returns for the final construction season

Project Announcement

April 13, 2026 - Northwestern Colorado - Crews will complete wildlife crossings, avalanche and rockfall mitigation and roadway work in 2026

Eagle County — Crews are returning on Monday, April 20, for the final construction season of the I-70 West Vail Pass Auxiliary Lane Project. The project, which began in 2021, aims to improve safety and operations on West Vail Pass by implementing significant infrastructure enhancements along the 10-mile stretch of I-70 between the East Vail Interchange (Mile Point 180) and the Vail Pass Rest Area (MP 190).

“As we enter the final season of this critical project, our focus is on a safe and successful project completion,” said CDOT Executive Director Shoshana Lew. “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."

In addition, CDOT 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 app.

Improvements scheduled for 2026

Working toward the completion of this project phase, crews will focus on remaining roadway and paving operations, finalizing wildlife crossings, and installing the avalanche and rockfall mitigation infrastructure. Work will also include landscaping and final improvements to the recreation path beneath the new bridges.

The project remains on schedule and is expected to be completed by the end of 2026.

Wildlife Crossings

Work will resume to complete the six wildlife underpasses — two for large animals and four for small to medium-sized animals. These crossings will go under I-70 between three miles west of Vail Pass (MP 187) and Vail Pass (MP 190). Wildlife fencing will also be completed between five miles west of Vail Pass (MP 185) and Vail Pass (MP 190) to reduce the risk of wildlife-vehicle collisions.

Avalanche and Rockfall Mitigation System

The project made major progress on a new avalanche and rockfall mitigation infrastructure in the area known as The Narrows (around MP 186). This system — the first of its kind in Colorado — will enable CDOT and the Colorado Avalanche Information Center (CAIC) 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.

Westbound I-70 Road Work

Additional road work and resurfacing on westbound I-70 will continue in 2026. The new pavement will improve traffic flow and the overall driving experience along West Vail Pass.

2026 Traffic Impacts

Motorists should anticipate increased activity and changing traffic patterns as the project moves toward its final configuration.

  • Beginning April 20, there is the possibility of daily single-lane closures along eastbound and westbound I-70 from MP 180 to 190.
  • In May, I-70 traffic will be shifted to the south into a head-to-head, barrier-separated alignment in the new eastbound lanes to allow for roadway and wildlife underpass construction.
  • From early to mid-June, rock-scaling activities will require traffic holds Monday through Thursday from 9:30 a.m. to 2:30 p.m. each day.
  • The window for helicopter operations requiring traffic holds runs from mid-June to early September. Only a few total traffic hold days are anticipated during this time to move equipment in and out of the area.
    • The traffic holds will last for about 20 minutes in both directions, but delays could be longer as the queues are cleared.
  • Night work is possible at the start of the season and is expected to be more consistent beginning this summer through the project’s completion.

Text Alerts for Major I-70 Impacts Return This Summer

Returning this summer, in addition to travel and road information found at COtrip.org and on the COtrip Planner mobile app, the I-70 West Vail Pass Auxiliary Lanes Project will continue a text alert notification service to notify motorists of expected impacts. I-70 Mountain Corridor travelers are encouraged to stay updated by texting vailpass (one word) to 21000 to receive regular communication.

2026 Recreation Path Impacts

The Vail Pass Recreation Path will remain open and accessible to riders and trail users this season, with impacts similar to previous years. Intermittent trail holds for construction access may occur, and variable trail conditions could exist through construction areas. Recreation path users should prepare for spring-like weather and trail conditions until regular maintenance begins just prior to Memorial Day weekend. There are no anticipated extended recreation path holds scheduled for the 2026 season.

Work Accomplished to Date

The project has accomplished significant milestones to date, notably the completion of two new bridges at MP 185.2, designed with a 100-year lifespan and improved curve geometry. Travelers are already enjoying the new 2.7-mile eastbound auxiliary lane between MP 187.3 and 190, which provides a dedicated climbing lane to separate slow-moving commercial vehicles from passenger traffic. Completed work also includes reconstruction of nearly two miles of the Vail Pass recreation path, enhanced drainage systems to protect Gore Creek, the installation of five miles of critical fiber-optic conduit for traveler information systems, the expansion of the U.S. Forest Service parking lot on Big Horn Road, and roadway resurfacing between MP 179 and 185. These improvements are highlighted in a short video found on the project page: codot.gov/projects/i70westvailauxiliarylanes.

Specialty crews rappelling along I-70 in “The Narrows,” in June 2025, to perform rock scaling as part of the new avalanche and rockfall mitigation system.
Specialty crews rappelling along I-70 in “The Narrows,” in June 2025, to perform rock scaling as part of the new avalanche and rockfall mitigation system.


Project Information

For additional information about this project:

Know Before You Go

Travelers are urged to “know before you go.” Gather information about weather forecasts and anticipated travel impacts and current road conditions prior to hitting the road. CDOT resources include:

Remember: Slow For The Cone Zone

The following tips are to help you stay safe while traveling through maintenance and construction work zones.

  • Do not speed in work zones. Obey the posted speed limits.
  • Stay Alert! Expect the unexpected.
  • Watch for workers. Drive with caution.
  • Don't change lanes unnecessarily.
  • Avoid using mobile devices such as phones while driving in work zones.
  • Turn on headlights so that workers and other drivers can see you.
  • Be especially alert at night while driving in work zones.
  • Expect delays, especially during peak travel times.
  • Allow ample space between you and the car in front of you.
  • Anticipate lane shifts and merge when directed to do so.
  • Be patient!

Download the COtrip App!

The free COtrip Planner mobile app was designed to meet the growing trend of information on mobile and tablet devices for the traveling public. The COtrip Planner app provides statewide, real-time traffic information, and works on mobile devices that operate on the iOS and Android platforms. Visit the Google Play Store (Android devices) or the Apple Store (iOS devices) to download!