CDOT previews construction phasing and summer construction closures for I-25 North Express Lanes Project, Mead to Berthoud

Travel Advisory

June 24, 2025 - Northeastern Colorado - Thank you from CDOT to Coloradans as crews kick off the summer construction season

Northeast Colorado —Summer means construction will heat up along with the weather on the I-25 North Express Lanes Project from Mead to Berthoud. The Colorado Department of Transportation is previewing some of the current and upcoming work so motorists know what to expect.

CDOT knew that replacing the aging infrastructure on the I-25 North corridor needed to happen sooner rather than later. The 70-year-old bridges, undersized drainage culverts, substandard roadway shoulders and under-capacity interchanges all needed updating for the longevity of this vital Colorado corridor.

A great deal of planning, work and progress has happened since the beginning of the broader I-25 North Express Lanes Project up to Fort Collins kicked off in 2018. Now, in the summer of 2025, 20 miles has been completed and the next 6-mile segment of the I-25 North Express Lanes Project, Mead to Berthoud, is approximately 50% complete. CDOT and the construction crews are taking advantage of warm, sunny, Colorado summer days to move efficiently on some major operations to keep the project on schedule despite the rainy late spring and early summer. I-25 users should expect construction impacts as the project continues so, please stay apprised to minimize travel impacts.

This summer, the project will implement traffic phasing to demolish the old structures and replace with the new. Here’s what is on deck for this summer:

Weld County Road 38 Bridge Demolition and Reconstruction:

The current Weld County Road 38 bridge was built in 1960, and a larger bridge is needed to span the widened I-25 section. The new bridge will have an 8-foot-wide sidewalk for multimodal connections over I-25. The new bridge will also be built “on alignment,” or in the same position as the current bridge, which was decided in coordination with the Town of Mead. Usually, CDOT replaces a bridge directly adjacent to the old bridge to allow the old bridge to be used during construction of the new bridge.

The reason for the departure from normal practices at WCR 38 is that Mead is currently working on a new interchange application in this area for review and approval by CDOT and the Federal Highway Administration. A final approval determination is expected in 2026. Multiple utilities exist in this area like waterlines, electrical lines, storm sewer lines, etc., so if the I-25 project elected to build the bridge to the north or south of the original bridge, then many expensive (more than $1 million) and lengthy utility relocations would have to occur, requiring their own closures of WCR 38.

With the possibility of the new interchange, these same utilities would have to get relocated again within a five-year period when the possible new interchange is designed and constructed. CDOT elected to build the bridge on alignment to save taxpayers sizeable money and be a good neighbor to our utility partners by not moving them multiple times within a close duration.

The demolition of the current bridge and the complete construction and roadway tie in of the new bridge will be completed while the WCR 38 east/west connection over I-25 is closed from June to December 2025.

CDOT is aware this six-month bridge outage is a significant inconvenience for daily users. Ultimately, this decision will invest money in permanent infrastructure in another area of the project and save Colorado taxpayer money. CDOT will prioritize keeping the Weld County Road 34 and I-25 interchange open during the WCR 38 bridge closure to help facilitate east/west movement across the interstate.

I-25 will be closed the nights of Monday, June 23, and Tuesday, June 24, 9 p.m. to 5 a.m., to demolish the bridge. Detour routes for the nightly I-25 closures will use state and US highways. Visit the North I-25 Express Lanes for traffic impact updates. CDOT is adjusting traffic signal timing at Colorado Highway 66 to accommodate the increased traffic the closures will cause.

Weld County Road 34 Bridge Demolition and Reconstruction:

Significant improvements are coming to the WCR 34 interchange, including:

  • New roundabouts to the east and west
  • A five-foot bike lane
  • An eight-foot sidewalk for safe multimodal travel over the interstate

The WCR 34 interchange will require complex construction phasing due to the sizeable amount of earthwork and paving, as the elevation of the interchange will be raised by approximately 6 feet. Various road closures will be required. At the same time, CDOT is coordinating with nearby projects in the area, including the High Plains Boulevard Project and various Little Thompson waterline projects.

These projects will require additional road closures in the area. The timing and length of closures in the WCR 34 interchange area are evolving, but all projects are communicating and coordinating together to ensure work is being completed in an efficient manner and information will be messaged in advance of detours.

Mainline I-25:

Earthwork and paving will continue on southbound I-25 through the summer and fall. This work includes widening the southbound I-25 footprint from 38 feet to 62 feet, like the completed segments to the north. The climbing lane of southbound I-25, from Colorado Highway 56 to WCR 38, will remain in place, and this specific two-and-a-half-mile section will have four 12-foot lanes: three general purpose lanes and one Express Lane to help slower moving vehicles navigate the long elevation gain while still allowing other traffic to safely navigate through this area.

In winter 2025, northbound and southbound traffic will transition over to southbound I-25 to complete work on northbound I-25 in 2026.

Thank you for your patience and flexibility as CDOT continues to improve I-25 and accommodate the approximately 90,000 vehicles a day traveling through the construction zone.

CDOT understands that motorists have encountered numerous road closures and travel impacts on the I-25 North corridor. The good news is that 20 miles have been completed, and Colorado travelers are already reaping the travel and safety benefits. Traffic frequently moves in a free-flow condition and the crash rate has dropped by more than 50%, compared to 2024 numbers and the five years prior to starting roadway construction (2014 to 2018).

Construction schedules are weather-dependent and subject to change.

Please visit codot.gov/projects/north-i-25, for the most current travel updates. The I-25 North Express Lanes Project: Mead to Berthoud section is a continuation of the approximately 20 miles of improvements that have been completed on I-25 between Berthoud to Fort Collins over the past six years. This approximately 6-mile project will expand and enhance I-25, from Colorado Highway 66 in Mead and connect to the newly built portion of I-25 just south of CO 56 in Berthoud. Once complete in 2028, this project will complete a major missing puzzle piece on I-25 and will be the first time there will be more than two lanes of I-25 from Denver to Fort Collins in both directions.

Stay informed:

For additional information about this project, contact the project team.

  • Project phone line - (720) 593-1996
  • Project email – [email protected]
  • Project web site - codot.gov/projects/north-i-25
  • Sign up for weekly project updates by logging onto the project web site and filling out the right-side form to “Subscribe to Project Updates.

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!

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