CDOT and contractor partners wrap up important I-70 safety improvements between Silverthorne and Eisenhower Johnson Memorial Tunnel

Summit County — The Colorado Department of Transportation and contractor partners Kraemer North America and Elam Construction have completed two important projects on the I-70 mountain corridor between Silverthorne and the Eisenhower Johnson Memorial Tunnel. Crews with Kraemer North America have finalized work on the I-70 Structure Replacement: West of the EJMT project and Elam Construction crews have wrapped up resurfacing east of Silverthorne. Representatives from both project teams, CDOT and agency partners gathered on Wed. Oct. 12 to celebrate both projects. Photos and video of the event and completed projects are available via the media kit.

“These projects are excellent examples of a long list of safety improvements underway along the I-70 mountain corridor,” said CDOT Chief Engineer Steve Harelson. “Other highlights along the corridor are a new eastbound auxiliary lane between Frisco and Silverthorne and the West Vail Pass Aux Lanes project.” Both auxiliary lane projects are underway now and will resume next spring after a winter shutdown. Work begins soon on significant safety improvements further east on Floyd Hill.

“I’d like to thank CDOT for the improvements along the I-70 mountain corridor, said Steve Greer, Interim Assistant County Manager for Summit County. “These improvements to I-70 in Summit County and along the corridor are critical to the economic success of communities here.”

Near the Eisenhower Tunnel, Kraemer North America crews replaced a failing culvert which serves an underpass under I-70. The underpass, or “box,” improves the structural integrity of I-70 in that location and ensures safe access for emergency services to motorists, as well as efficient maintenance and plowing operations.

“This is the most critical culvert on Colorado’s state highways,” said Director of Maintenance and Operations John Lorme. “It can continue to provide critical access for services that are necessary for keeping I-70 safe and open to the public. This includes CDOT plow drivers, Colorado State Patrol, tow services and other emergency services.”

The project was completed on schedule and on budget. The new structure is only open to authorized vehicles such as snowplows, ambulance services and law enforcement and is ready for use during the upcoming winter driving season. The previous structure, a single-lane concrete box culvert, was built in the late 1960s during the original construction of I-70. The old structure was in poor condition and considered functionally obsolete.

“Thanks to historic investments in transportation through measures including the state’s historic bipartisan transportation bill and new federal funds, we are finally taking on the backlog of major repair needs surrounding the Eisenhower Johnson Memorial Tunnels, which require about $150 million in long-needed repairs,” said CDOT Executive Director Shoshana Lew. “As we complete these important safety projects in the critical segment of the I-70 mountain corridor surrounding the tunnels, CDOT will be moving quickly towards more improvements in area in the upcoming construction seasons.”

During the 2022 construction season, crews with Elam Construction resurfaced eastbound and westbound I-70 from Silverthorne to the Eisenhower Johnson Memorial Tunnel. Final work on the I-70 Silverthorne to EJMT Resurfacing Project wraps up this week, as crews complete striping (painting) operations.

“This is a challenging section of roadway to complete road construction projects,” said Region 3 Transportation Director Jason Smith. “Running several projects at the same time is even more difficult. The engineering teams worked closely with each other and CDOT maintenance crews to streamline traffic impacts wherever possible, and complete these projects with limited construction season.”

During the resurfacing project, work took place along I-70 for 5 miles from approximately Mile Point 206, by Silverthorne, to approximately MP 212, slightly west of the Eisenhower Johnson Memorial Tunnel. Crews placed a 2” hot mix asphalt overlay, installed new guardrail, repairing the end transition rails and bridge rails and culvert installation. Crews also completed essential bridge work.

The hot mix asphalt will add approximately 10 years of life to the highway, provide a smoother road surface and will durability by increasing the resistance to ruts and road damage. This will allow for a smoother and safer drive for motorists. New guardrail is 31 inches high, designed to meet new safety standard requirements. The higher railing will help veering vehicles remain on the road more effectively, making the highway safer for the traveling public. The former standard height of the guardrail was 27 inches.

More about the I-70 Structure Replacement

During construction, project crews safely managed 11 traffic switches and four separate girder installations while keeping reliable interstate travel, sometimes in the challenging continental divide terrain and weather conditions. Crews maintained two westbound and three eastbound travel lanes using various lane closure strategies to keep traffic moving efficiently. Sequential shifts of westbound and eastbound I-70 traffic allowed the project team to install girders and build the new bridges along I-70 in tight right-of-way conditions.

Crews completed the westbound bridge in 2021 before entering a winter construction hiatus. When the team returned to work in April, they first constructed the remaining eastbound bridge, guardrails and permanent concrete barrier.

Concurrently, crews demolished the old box culvert below the highway while building the new underpass, reconstructing approximately 1,900 feet of the access road. The new structure is 36 feet wide, accommodating two-way traffic and improving the approach turning radius. The new underpass will provide safe access for emergency services to assist motorists and more efficient maintenance and plowing operations.

Following completion of the new bridge and median, the project team repaved and restriped I-70 through the project limits. The final product also includes erosion control measures, landscaping and aesthetic components.

Other I-70 Projects

Other projects on I-70 are happening in close proximity. These each have their own prime contractors and construction teams. More information on these projects can be found on the project-specific websites or by visiting COtrip.org for real-time impacts on CDOT projects across the state. The I-70 construction teams are in close communication to help keep the public informed.