CDOT seeks public input on I-70 Mountain Corridor Improvements between Floyd Hill and Idaho Springs

News Release

August 10, 2021 - Review project plans and share input online

Go online to review project plans and share input

CLEAR CREEK COUNTY - The public is invited to review and share comments on the I-70 Floyd Hill to Veterans Memorial Tunnels Environmental Assessment (EA), released last week online by the Colorado Department of Transportation. The next critical step toward construction is public review and input of the EA, which explains CDOT’s Preferred Alternative to revamp seven miles of I-70 between Floyd Hill, west of Evergreen, and the Veterans Memorial Tunnels, east of Idaho Springs (see rendering below). 

Visit the EA virtual room to learn more about the project and share comments.

EA Virtual room design

Rendering of the Preferred Alternative to improve I-70 Floyd Hill (see details below)

Rendering of the preferred alternative to improve I-70 Floyd Hill

This section of the mountain corridor has not had significant improvements since it was built several decades ago. There are tight bottlenecks and a dire need to replace the aging westbound I-70 bridge at the bottom of Floyd Hill. The project will relieve congestion, rebuild bridges, enhance multi-modal travel, improve wildlife habitat and access to Clear Creek and the Clear Creek Greenway. CDOT has been working collaboratively with local communities, state and federal agencies, environmental groups, and other stakeholders for the past several years to develop a solution for this vital stretch of highway.

“CDOT is able to move ahead on this important corridor because of the extensive planning and community involvement that has led to the most reasonable and practical solution to relieve traffic, provide multi-modal options and increase safety on this heavily traveled section of the mountain corridor,” said CDOT Executive Director Shoshana Lew. “Thanks to recent transportation funding legislation signed into law by Gov. Jared Polis, we have the funding for substantial construction and will be ready to start early projects next year. Along the way, we will continue to get stakeholder input as public collaboration is the key to the success of this project.”

Preferred Alternative:

The Preferred Alternative has been carefully designed to minimize community and environmental disruption and enhance the natural beauty of the area. The interstate would be elevated above the canyon (see rendering above), similar to the stretch through Glenwood Canyon west of Vail, to offer drivers a scenic view of this gateway to the mountains and remove the highway from the floor of the canyon, opening it up to improved wildlife and recreational uses.  

Key improvements include: 

  • Adding a third westbound travel lane from Floyd Hill (where the highway currently narrows from three to two lanes) through the Veterans Memorial Tunnels and reconstructing horizontal curves to provide more consistent and safer speeds.
  • Adding a missing frontage road connection between US 6 and the Hidden Valley/Central City Parkway interchange to provide an alternate route to I-70 during emergencies and improving the Clear Creek Greenway trail for multimodal and recreational users. 
  • Improving interchanges and intersections throughout the project area.
  • Adding an auxiliary lane to I-70 in the eastbound (uphill) direction of Floyd Hill between the US 6 interchange and the Hyland Hills/Floyd Hill interchange.
  • Reducing animal-vehicle conflicts and improving wildlife connectivity.
  • Providing two permanent air quality monitors at Floyd Hill and Idaho Springs to collect data on local air quality conditions and trends.
  • Coordinating rural broadband access with local communities, including providing access to existing/planned conduits and fiber in the interstate right of way. 
  • Implementing a new micro-transit service from Denver to the mountains including three park-and-ride facilities and regular service in vehicles that are sized to utilize peak period shoulder express lanes.

Estimated schedule and cost:

The Project is planned to be phased and funded incrementally. Construction could begin as early as 2022 with some high-priority early improvements, such as wildlife crossings and intersection improvements at Floyd Hill, that would minimize community and environmental impacts during construction. Major westbound I-70 construction is estimated to begin in 2023. The estimated cost is $700 million. 

EA background and info and how the public can get involved:

The EA describes the reasons for the project and the different improvement alternatives that were considered, identifies the Preferred Alternative that could advance into design and construction, explains the environmental and community impacts of the project, and details how the public and stakeholders provided input to shape the project. The public is encouraged to review the EA document and associated virtual public engagement materials developed to support the EA review: