Project Background

Growth and tourism in and around Vail have increased congestion on the roads most traveled in the area (interchanges from I-70 and along the north and south I-70 frontage roads). The idea of an additional underpass between West Vail and Main Vail has been discussed since the 1980s as a way to enhance connectivity and reduce congestion at the West Vail and Main Vail interchanges.

The I-70 Vail Underpass project will add an I-70 underpass near I-70 mile point 175, connecting the north and south frontage roads between the Main Vail and West Vail interchanges.

Construction, which started in April 2016, is scheduled to be completed in November 2017. Work hours will vary based on the construction phase (see below). The tentative project schedule aims to reduce construction impacts during the winter tourism season.

The first major phase of construction involved moving I-70 traffic into a single lane, barrier-separated configuration on one side of the highway while the bridge on the opposite side was built. I-70 traffic was initially shifted to the south side of the highway (in the eastbound lanes) to build the westbound bridge.

Once the westbound bridge was completed, traffic was shifted to the north side of the highway (westbound lanes) while the eastbound bridge was built. Both of the underpass bridges were completed by July 1, 2016.


This phase included extensive work along the north and south frontage roads. The roads were excavated and lowered 15 feet, 10 utility lines totaling 4.36 miles were lowered and relocated, and a new storm sewer facility and retaining walls to support the new underpass were built.


This phase consists of a winter slowdown of major construction to allow for a normal traffic alignment along the north and south frontage roads during the winter tourism season.

There is the potential for minor construction activities beneath the underpass, although no night or week work is anticipated.

Traffic Impact:
The frontage roads' normal two-way operation through the construction site will continue, allowing eastbound and westbound travel on both the north and south frontage roads. I-70 is in its normal two-lane, two-way traffic alignment.

The new underpass will be closed during phase 3 to both vehicle and pedestrian traffic.

Bikes and Pedestrians:
Access to the Gore Creek Trail on the east end of the project site (adjacent to the Glen Lyon offices) is open to pedestrians and bicyclists. Pedestrians on the south frontage road are advised to use the Gore Creek Trail.

The North Recreation Path, adjacent to the north frontage road, is open in its new at-grade alignment.

This phase focused on the construction of the underpass roundabouts. The area beneath the underpass was also fully built, including brick pavers, curb and gutters, and lighting elements. This phase also included construction of elevated sidewalks with pedestrian guardrails. Finer detail work—namely landscaping and aesthetic components were also completed.

Construction Timelapse Video