North America's Premier International Resort Community

CDOT and FHWA Finalize Environmental Assessment for Proposed West Vail Pass Improvements

  • 2 March 2021
CDOT and FHWA Finalize Environmental Assessment for Proposed West Vail Pass Improvements

Improvements on West Vail Pass along Interstate 70 can move forward this year, thanks to a major milestone completed by the Federal Highway Administration and the Colorado Department of Transportation. CDOT and FHWA recently signed the Finding of No Significant Impact for the Proposed Action documented in the Environmental Assessment and Section 4(f) Evaluation of West Vail Pass. The approval is required by federal law and establishes that the proposed improvements to West Vail Pass meet the needs of the corridor.

The Proposed Action is a package of improvements for both eastbound and westbound I-70 from the eastern side of the Town of Vail, miler marker 179.5, to just beyond the Vail Pass rest area at the top of the pass, mile maker 191.5.

Construction of the first phase of improvements can begin this summer. CDOT has obtained $140.4 million to fund the first phase, including a $60.7 million Infrastructure for Rebuilding America grant awarded by the U.S. Department of Transportation. The first round of work will include an eastbound auxiliary lane from mile marker 185 to the rest area at mile marker 190. Other improvements include a widened inside shoulder, reconstruction of tight curves, wildlife underpasses and fencing, water quality improvements, truck ramp enhancements, median glare screens and relocation of two miles of the recreation path that is currently next to I-70. The latest technology will be used to add variable speed limit and message signs and a way to close the pass immediately through a remote system when necessary.

A detailed description and evaluation of the Proposed Action is documented in the Environmental Assessment  and Section 4(f) Evaluation, which considers benefits, impacts, and proposed mitigation for numerous environmental and community resources. The EA and Section 4(f) Evaluation can be found on the project web page:

CDOT conducted a 30-day public review period in Fall 2020. Due to limitations on public events during the pandemic, CDOT conducted a virtual public engagement period by providing information online about the Proposed Action in the Environmental Assessment and Section 4(f) Evaluation. Information online included a video summarizing the study, findings, and next steps, as well as printed copies provided at the Vail Public Library and Town of Vail administration office. During that comment period, the majority of comments came from East Vail residents; many comments focused on traffic noise analysis. Public input was considered by CDOT and the Federal Highway Administration prior to issuing the decision document.

The original 1-70 alignment over Vail Pass was analyzed in the 1973 Vail Pass Environmental Impact Statement. Construction of this section of I-70 was completed in 1978. The original design of I-70 on West Vail Pass was groundbreaking at the time due to the context sensitive nature of the design, intended to blend the interstate into the existing landscape and minimize environmental impacts.

In 2011, as part of the National Environmental Policy Act, the I-70 Mountain Corridor Programmatic Environmental Impact Statement was completed between C-470 and Glenwood Springs. This document analyzed potential safety, capacity and operational improvements along the I-70 Mountain Corridor. This high-level analysis recommended the addition of auxiliary lanes eastbound and westbound on the west side of Vail Pass between mile marker 180 and mile marker 190.

In 2017, CDOT and FHWA began a more detailed NEPA analysis for assessing improvements to I-70 on West Vail Pass. This process is now complete with the recently signed Finding of No Significant Impact and completed EA and Section 4(f) Evaluation.



  • Gallery

Theme picker