Vail Pass megaproject enters its final winter before completion
CDOT expects to wrap the five-year, 10-mile rebuild by the end of 2026, finishing wildlife crossings and a first-of-its-kind avalanche mitigation system.
After five construction seasons, the I-70 West Vail Pass Auxiliary Lanes project is in its final year, with the Colorado Department of Transportation expecting to finish the work by the end of 2026.
The project, which began in 2021, rebuilds a 10-mile stretch of I-70 between the East Vail interchange at mile point 180 and the Vail Pass rest area at mile point 190, one of the most crash-prone and closure-prone segments of the I-70 mountain corridor. Crews returned April 20, 2026 for the final construction season, CDOT said in an April release.
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.
Shoshana Lew, CDOT Executive Director (April 13, 2026 CDOT release)
Completed work to date includes two new bridges at mile point 185.2, built with a 100-year design lifespan and improved curve geometry, and a 2.7-mile eastbound auxiliary lane between mile points 187.3 and 190 that gives slow-moving trucks a dedicated climbing lane up the pass. CDOT also lists nearly two miles of rebuilt recreation path, drainage improvements to protect Gore Creek, five miles of fiber-optic conduit for traveler information systems, an expanded U.S. Forest Service parking lot on Big Horn Road and resurfacing between mile points 179 and 185.
What is left to build
The final season's work centers on six wildlife underpasses, two for large animals and four for small to medium-sized animals, going under I-70 between mile points 187 and 190, plus wildlife fencing between mile points 185 and 190 to reduce vehicle collisions. Crews are also installing an avalanche and rockfall mitigation system at an area known as The Narrows, around mile point 186, which CDOT describes as the first of its kind in Colorado. The system is designed to let CDOT and the Colorado Avalanche Information Center monitor and manage a known avalanche path, reducing the likelihood of extended interstate closures.
What winter drivers should know
CDOT has paused the project each winter; during the 2025-26 winter shutdown the agency said no lane closures were expected, with only minor work away from the roadway. With completion targeted for the end of 2026, winter 2026-27 travelers should still check conditions before driving the corridor. COtrip.org and the COtrip Planner app carry real-time road information, and drivers can text the word vailpass to 21000 for project alerts. Vail Tribune does not publish live road conditions; always check official sources before traveling.
