Westbound I-70 Twin Tunnels Weekly Traffic Advisory

April 25, 2014 - Central Eastern Colorado/CDOT Region 1 - IDAHO SPRINGS – Work on the Westbound Twin Tunnels project is underway. This Colorado Department of Transportation (CDOT) project will widen the westbound tunnel bore to accommodate future expansion in the I-70 mountain corridor.

Both lanes of I-70 have been moved onto to detour routes. Eastbound traffic has been shifted to the frontage road around the tunnel while westbound traffic has been moved into the eastbound tunnel. Traffic will be in this alignment throughout construction which is scheduled for completion in December 2014. Now that traffic has been moved onto the detour routes, crews are performing regular rock scaling along the east and west portals. Rock scaling is when crews traverse the rock face and pull loose boulders and debris from the mountainside. This results in large and small rocks and boulders tumbling down the rock face and onto the lanes of traffic below. The first tunnel blast was taken on Wednesday, April 16. Blasting operations will continue and exact dates and times will be released 24 hours prior to a blast taking place. It is important to remember that crews may change the exact time of a blast should safety or other conditions dictate. Once crews have completed the section for that closure crews then must clear the roadway of the fallen debris in order for traffic to continue. For up to date information on rock scaling and blasting operations please download our gov delivery notifications by visiting and clicking on the green cell phone icon.

Lane closures are scheduled as follows, all work is weather permitting:

  • Saturday,  April 26
    • No closures scheduled
  • Sunday,  April 27
    • No closures scheduled
  • Monday,  April 28
    • 5 a.m. – 4 p.m. – Left lane closure eastbound and westbound at exit 243
    • 5 p.m. – 5 a.m. – Single lane closures eastbound or westbound
  • Tuesday,  April 29
    • 7 a.m. – 9:30 a.m. – Single lane closures eastbound or westbound
    • 5 p.m. – 5 a.m. – Single lane closures eastbound or westbound
  • Wednesday, April 30
    • 7 a.m. – 12 p.m. – Single lane closures eastbound or westbound
  • Thursday, May 1
    • 7 a.m. – 9:30 a.m. – Single lane closures eastbound or westbound
  • Friday, May 2
    • No closures scheduled
  • Saturday, May 3
    • No closures scheduled
  • Sunday, May 4
    • No closures scheduled

Blasting operations are likely to take place during this time resulting in full closures in both directions and delays along this corridor. This blasting schedule will work in collaboration with the rock scaling schedule if rock scaling operations are in underway. When blasting operations take place, both directions of I-70 will be stopped to ensure public safety. As soon as crews are able to clear the area, traffic will be released. In order to receive updated reports on the blasting and scaling schedules for this project sign up for text or email alerts by visiting and clicking on the green cell phone icon in the upper right hand corner of the homepage.

Blasting operations will occur several times a week throughout the spring and summer. These closures will consist of full stopping of traffic in both directions for blasting and subsequent closures also in both directions for scaling operations. Delays will exceed the time that traffic is stopped and Drivers should be prepared for longer than normal travel times for the duration of this project. While scaling operations are taking place, multiple closures will be implemented each day. CDOT recommends that drivers plan visit, call 511 or download the mobile app for updated information on travel times in this area.

CDOT estimates widening the westbound tunnel now will save $5 million to $7 million because the equipment, resources and detour needed to do the work are already in place. Tunnel widening work is scheduled to be complete by the end of this year and at that time all I-70 traffic will be back in its regular alignment. Project completion is scheduled for summer 2015 when County Road 314 is restored to its original configuration with completed facia walls and an improved recreational trailhead.

To receive real-time updates about road conditions in your area, visit and click on the green cell phone icon in the upper right hand corner of the page. Information about weekly lane closures will be available at Live road conditions are available at, downloading the CDOT Mobile app or by calling 511 from anywhere in the state. Updates are also available via Twitter @coloradodot and be sure to “Like” our Facebook page at

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