If you regularly travel the I-70 Mountain Corridor, you know Floyd Hill.
It’s where westbound traffic can quickly back up as three lanes become two. It’s where steep grades and tight curves can make driving challenging, particularly in winter weather. And it’s a critical connection between the Denver-metro area and Colorado’s mountain communities.
That’s why CDOT is transforming eight miles of I-70 between west of Evergreen and eastern Idaho Springs through the I-70 Floyd Hill Project.
Construction began in July 2023, but the need for improvements goes back decades. Here are 10 reasons the Project is important to the future of the I-70 Mountain Corridor.
1. Address one of I-70’s biggest bottlenecks
Westbound I-70 currently narrows from three lanes to two near the top of Floyd Hill, creating a significant bottleneck during busy travel periods – and without improvements, congestion is projected to get considerably worse.
According to traffic modeling completed as part of the Project’s environmental analysis, by 2045, a westbound trip through the Project area during the winter Saturday peak could take more than 90 minutes if improvements aren’t made, with peak congestion potentially lasting as long as 12 hours. With the Project improvements, that same trip is projected to take less than 30 minutes during peak conditions, with a significantly shorter period of congestion.
The Project will add a third westbound travel lane through this section, operating as a full-time tolled Express Lane, to create more consistent capacity and improve travel-time reliability.
2. Improve safety through Floyd Hill
Floyd Hill’s existing steep grades, tight curves and limited sight distances can create challenges for motorists.
The Project will realign portions of I-70 and straighten roadway curves to improve sight distance and provide more consistent travel speeds through the corridor.
3. Replace aging bridges
Some bridges within the Project limits have served I-70 motorists for decades and need to be replaced because of age, wear and heavy use.
The Project will rebuild and replace bridges to meet today’s safety standards and accommodate the future alignment of I-70.
4. Give slow-moving vehicles more room
Anyone who has traveled eastbound up Floyd Hill behind a slow-moving truck knows how quickly traffic can stack up.
An extended on-ramp from US 6 to eastbound I-70 will give trucks and other slow-moving vehicles more room to accelerate and merge, reducing conflicts with through traffic.
5. Create another connection when I-70 is blocked
Today, there is a missing section of frontage road between the US 6 and Hidden Valley/Central City Parkway interchanges.
The Project will fill that approximately two-mile gap, creating an important alternate connection that can improve emergency response and corridor resiliency when incidents occur on I-70.
6. Improve interchanges and intersections
The Project isn’t only about the interstate. Improvements to interchanges and intersections throughout the Project area are designed to improve traffic flow and access for residents, businesses and travelers. That includes improvements at Hidden Valley/Central City Parkway and the new roundabouts on US 40 at County Road 65 and Homestead Road.
7. Make room for safer wildlife movement
The I-70 Mountain Corridor passes through important wildlife habitat. Improvements associated with the Project include wildlife crossings – including the I-70 & Genessee Wildlife Underpass in Evergreen – fencing along I-70 and other environmental mitigation designed to improve wildlife connectivity and reduce conflicts between animals and vehicles.
8. Improve the Clear Creek Greenway
The Project also includes improvements to the Clear Creek Greenway, an important recreational and multimodal connection through Clear Creek County.
When complete, Greenway improvements will provide a better experience for pedestrians and cyclists while maintaining access to the natural resources that make this corridor special.
9. Invest in the corridor beyond the roadway
Improving I-70 isn’t just about adding pavement. The Project includes environmental mitigation focused on wildlife connectivity, air and water quality, stream conditions and recreation. Two permanent air quality monitors will collect information about conditions and trends in the Floyd Hill and Idaho Springs areas.
10. Build a more reliable I-70 Mountain Corridor for the future
Perhaps the biggest reason for the Floyd Hill Project is that I-70 serves a much larger role than getting travelers to their favorite mountain destination.
The corridor connects mountain communities, businesses, residents, visitors and freight movement while serving as an important economic gateway for Colorado and the nation. Improving safety, reliability and resiliency at Floyd Hill benefits everyone who depends on the corridor.
Building the Future of Floyd Hill
Major construction inevitably brings short-term impacts, but travelers are already beginning to see the future of I-70 take shape.
With major rock blasting substantially complete, construction is increasingly focused on bridges and roadway improvements. New bridge columns and structures are becoming visible throughout the Project area, including The Live Lift, the new cast-in-place segmental bridge that will carry westbound I-70 above the existing highway near US 6.
The transformation won’t happen overnight, but each construction milestone brings the I-70 Mountain Corridor closer to a safer, more reliable and resilient future.
While work continues, travelers can do their part by planning ahead, checking conditions before leaving and allowing extra time through the construction zone.
For more information on the Project, and to sign up for weekly emails and construction text messages, visit https://www.codot.gov/projects/i70floydhill.