Planning to explore Colorado’s Rocky Mountains this summer? Here’s how road work could impact travel in and around Summit County.

Traffic from Interstate 70 takes Exit 205 into Silverthorne on March 25, 2021.
Ashley Low/Summit Daily News archive

Summer is a beautiful time to explore the Rocky Mountains. From hiking to camping, rock climbing, boating, fly fishing, rafting and more, Summit County offers endless outdoor experiences, attracting thousands of visitors a year.

But, after an especially harsh winter damaged local roadways, warmer weather also means its road construction season. With one major project already underway on Interstate 70, Summit County residents and visitors should be prepared for road construction that could impact travel plans this spring and summer.

Here’s what projects the Colorado Department of Transportation has planned for the upcoming months. Real-time traffic impacts of many of these projects can be observed online at

This map shows the boundaries of roadwork along Interstate 70 that began Monday, April 10, 2023.
Colorado Department of Transportation/Courtesy photo

I-70 Frisco to Silverthorne auxiliary lane

In April, the crews resumed work on the I-70 auxiliary lane project between Frisco and Silverthorne and construction activities are expected to continue through the fall.

Motorists should plan for about 20 additional minutes of travel time through the construction zone along the stretch of highway from mile markers 202 to 207, according to CDOT. Typical daytime construction will occur between 7 a.m. and 5:30 p.m. Monday to Friday, with minimal impacts after noon on Friday.

The project will widen the road, create a new eastbound auxiliary lane, repave and re-stripe lanes, widen bridges over U.S. Highway 6 and the Blue River, improve truck parking at the eastbound scenic overlook and create in a longer deceleration lane and improve signage at the Exit 205 off-ramp, the CDOT website states.

The I-70 overlook east of Frisco’s on-ramp at Exit 203 will be closed for construction staging through the duration of the project. 

The eastbound Exit 205 off-ramp will be a single-lane exit during construction, speed limits in the construction area will be reduced to 55 mph and eastbound lanes will be shrunk to 11 feet, the release states. Overnight construction hours will vary and result in single-lane and shoulder closures in both directions, according to CDOT. Temporary concrete barriers will be in place throughout the project.

The auxiliary lane project will significantly improve safety on this busy section of I-70, which is a corridor with a higher-than-average crash rate, a transportation department spokesperson said in an email.

The high crash rate causes delays for emergency response and partial interstate closures, according to CDOT, and the new eastbound auxiliary lane will allow emergency services to more easily reach vehicle crashes during those closures.

It is possible that the new auxiliary lane could decrease the need for, or length of, safety closures during snowstorms and other events.

Colorado Highway 9 north of Silverthorne and south of Kremmling

A map shows where resurfacing road work will take place beginning in May 2023.
Colorado Department of Transportation/Courtesy photo

Beginning this month, construction on Colorado Highway 9 from mile markers 107 to 113, north of Silverthorne, and from mile markers 126 to 137, south of Kremmling, will improve asphalt conditions, upgrade guardrails and striping, signage and shoulders, according to CDOT.

Work will occur between 7 a.m. and 5:30 p.m. Monday to Friday and is expected to be completed by mid-October. Travelers should plan for one-lane, alternating traffic guided by a pilot car and 20-minute delays. Bicycles will be shuttled through the work zone.

Northwest Colorado region-wide epoxy striping

Colorado Department of Transportation/Courtesy photo
A map shows where resurfacing road work will take place beginning in May 2023.
Colorado Department of Transportation/Courtesy photo

Also in May, the transportation department will begin a regional striping project along I-70, U.S. Highway 40, U.S. Highway 6 and Colorado Highway 9.

Minimal to no traffic impacts are expected.

I-70 West Vail auxiliary lanes

Colorado Department of Transportation/Courtesy photo
A bridge pier for the future westbound bridge at Interstate 70 mile marker 185. Construction of the westbound bridge will be an early focus for construction crews beginning May 1, 2023.
Colorado Department of Transportation/Courtesy photo

This month, work will resume on the West Vail Pass Auxiliary Lanes project, which is entering its third season and this year will focus on the construction of a mile marker 185 westbound I-70 bridge, among other improvements, according to CDOT.

This year’s work will involve narrowed lanes and shoulders along I-70, lane closures and temporary traffic holds along the recreation trail. Rock blasting began May 1 and light evening delays are expected.

During these short blasts, I-70 traffic and recreation trail users will be stopped in both directions for up to 30 minutes. Motorists can sign up for day-of notifications about blasting and travel delays associated with this project at

Traffic holds will only be scheduled between Monday and Thursday, usually between 6-8 p.m., and are expected to occur once per day until blasting work is completed. Shrine Pass Road will be closed during blasting activities. The Vail Pass rest area will be closed through October 2023 for reconstruction.

Work on the foundation for the new westbound I-70 bridge over Polk Creek near mile marker 185 began last year, and both I-70 bridges in this area will ultimately be rebuilt, according to CDOT, starting with the westbound bridge.

Additional work planned to start this summer will include the construction of six wildlife crossings and fencing and initial work on the eastbound auxiliary lane from mile posts 185 to 190.

Colorado Department of Transportation/Courtesy photo
A map shows eastbound Interstate 70 single lane closures over Loveland Pass for a bridge rehabilitation project expected to wrap up by the end of May 2023.
Colorado Department of Transportation/Courtesy photo

Emergency bridge rehabilitation on eastbound I-70 near Eisenhower-Johnson Tunnels

Work that began April 10 to rehabilitate a bridge on eastbound I-70 just east of the Eisenhower-Johnson Tunnels is expected to wrap up by the end of May, according to CDOT. The work will take place near mile marker 216 on the bridge over Loveland Pass.

The rehabilitation is necessary to fix a large pothole that formed in mid-March. The majority of traffic impacts are expected to occur between 9 p.m. and 9 a.m. Sunday and Thursday, but some daytime work will also be necessary.

Drivers can expect single-lane closures, meaning eastbound traffic on I-70 will be reduced to one lane during the project’s work hours. Reduced speeds and uneven pavement surfaces in the work zone should also be expected, according to CDOT.