Construction projects to expect on popular Colorado mountain routes this summer

Travel Advisory

May 28, 2025 - Colorado - Projects aim to ensure safer, smoother travel for the millions of residents and visitors

Statewide — As Colorado travel enthusiasts prepare for road trips across the state, so is the Colorado Department of Transportation (CDOT) enhancing highway infrastructure. Critical construction projects are happening across Colorado’s mountain corridors and passes on the way to popular attractions with noticeable impacts starting in June, in some areas.

Due to Colorado's long winter season, which brings nearly eight months of snow to many mountain areas, CDOT maximizes the non-winter months to complete crucial road upgrades. With essential safety improvements already underway, this summer’s projects aim to ensure safer, smoother travel for the millions of residents and visitors who flock to and around Colorado.

Map of Summer 2025 construction projects along US 40 Mountain Corridor in Grand County
Featured map, hosted on codot.gov, highlights construction projects along US 40 in Grand County during summer 2025.

Popular Colorado Summer Routes and 2025 Active Projects

Northwestern Colorado

  • I-70 Mountain Corridor: June and July bring significant impacts, including traffic holds for rock scaling and blasting, along the corridor between the I-70 Floyd Hill Project and Vail Pass Auxiliary Lane Project, along with five other planned improvement projects. Daytime traffic holds on I-70 and delays can be expected for both the I-70 Floyd Hill Project and Vail Pass Auxiliary Lane Project as crews perform rock scaling and blasting.
  • US 40: Grand County: Along US 40 from Empire through Winter Park to just prior to Granby, travelers will encounter three improvement projects that are expected to cause weekday impacts, primarily focused on resurfacing and safety improvements. Visit the US 40: Grand County webpage for a map and additional information about the three projects.
  • CO 82: Twin Lakes: Along the popular CO 82, from Twin Lakes over Independence Pass to Glenwood Springs, motorists will experience three projects focused on resurfacing and safety improvements.

Northeastern Colorado

  • US 34 and US 36 Resurfacing: Motorists headed toward Estes Park and the east entrance of Rock Mountain National Park will encounter one project enhancing road safety.

Southwestern Colorado

  • US 160 Pagosa Springs Reconstruction: Archuleta County, construction in downtown Pagosa Springs. Utility upgrades, replacement of asphalt surface to concrete, sidewalk and pedestrian improvements.
  • US 550 Coal Bank Pass Wall Replacement: San Juan County, work between Durango and Silverton. Rockfall mitigation near Deer Creek and under-highway wall replacement near the summit of Coal Bank Pass.
  • US 160 West Wolf Creek Pass Resurfacing: Mineral County, overlay paving on the west side of Wolf Creek Pass from Treasure Falls to the pass summit. Work also includes deck repairs on the bridge just east of Treasure Falls as well as a culvert inlet repair.
  • US 160 Fort Garland East Safety Mitigation: Costilla County, improvements to US 160 between Fort Garland and La Veta Pass. Installation of three wildlife underpasses, acceleration and deceleration lanes, intersection improvements.

Southeastern Colorado

Motorists should expect reduced speed limits and lane closures during non-peak travel times for many of these projects. To stay safe, drivers should obey posted speed limits, avoid distractions and anticipate lane shifts.

Additional Travel Resources

  • Travel the I-70 Mountain Corridor car-free! Hop on Bustang or Pegasus in the Denver metro area to travel to many mountain destinations. Once you arrive at your destination, use local free transit to get around. Visit GoI70.com/transit and RideBustang.com to learn more.
  • In addition to expected roadway work, while rockfalls can occur at any time of year, officials typically see an increase in incidents as temperatures rise. The COtrip Planner App offers a "Report Rockfall" feature, which sends information directly to CDOT’s operations centers, allowing crews to respond quickly. The reported details—such as location, date and time, photos, and notes—help ensure that teams are fully informed and can assess the situation efficiently.
  • Motorists should always use COtrip.org and COtrip Planner App before hitting the road when planning summer travel.

Know Before You Go

Travelers are urged to “know before you go.” Gather information about weather forecasts and anticipated travel impacts and current road conditions prior to hitting the road. CDOT resources include:

Remember: Slow For The Cone Zone

The following tips are to help you stay safe while traveling through maintenance and construction work zones.

  • Do not speed in work zones. Obey the posted speed limits.
  • Stay Alert! Expect the unexpected.
  • Watch for workers. Drive with caution.
  • Don't change lanes unnecessarily.
  • Avoid using mobile devices such as phones while driving in work zones.
  • Turn on headlights so that workers and other drivers can see you.
  • Be especially alert at night while driving in work zones.
  • Expect delays, especially during peak travel times.
  • Allow ample space between you and the car in front of you.
  • Anticipate lane shifts and merge when directed to do so.
  • Be patient!

Download the COtrip App!

The new free COtrip Planner mobile app was designed to meet the growing trend of information on mobile and tablet devices for the traveling public. The COtrip Planner app provides statewide, real-time traffic information, and works on mobile devices that operate on the iOS and Android platforms. Visit the Google Play Store (Android devices) or the Apple Store (iOS devices) to download!