I-25 Central Denver Resurfacing

About the Project

The project will improve and resurface a heavily traveled five-mile stretch of Interstate 25 in central Denver from Alameda to 44th avenues. Improvements will include:

  • New pavement
    • Work involves rotomilling, which removes the old, weathered asphalt to be replaced with new asphalt.
    • This section of I-25 was last resurfaced in 2015.
  • Repaired expansion joints between the roadway and bridges
  • New signs
  • Restriping
  • New concrete barriers
    • The project will replace 2,700 linear feet of old concrete barrier segments with new segments along I-25 near the South Platte River between the US 6 entrance ramp to southbound I-25 to the end of the southbound I-25 exit ramp to Alameda Avenue.
    • The new barriers will be stronger and taller structures, 36 inches high and 24 inches thick at the base with steel reinforcement within the concrete. 

Lane and ramp closures will be mostly overnight. Work begins in early April to replace the barriers next to the South Platte River, which will require overnight ramp closures: US 6 on-ramps to southbound I-25 and the southbound I-25 off-ramp to Alameda Avenue.  These closures will last for about a month.  When the weather gets consistently warmer in May there will be up to three lanes closed overnight on I-25 in both directions. Adjustments will be made for events. More detailed information on traffic impacts is below. 

Motorists are urged to drive with extreme caution through the work zone. 

Work this Week & Lane Closures on I-25 Central Denver

Project Facts

  • Construction Cost: $22 Million
  • Contractor: Asphalt Specialties CO, Inc.
  • Timeline: April 2025 to January 2026
  • Location: I-25 
    • Nearest Town/City: Denver
    • Mile Point(s): MP 208 to MP 213.5
    • County: Denver
Project location map for I-25 resurfacing in central Denver, Colo.
Project location map for I-25 resurfacing in central Denver from Alameda to 44th avenues.

Project Benefits

The resurfacing will provide the following benefits:

  • Prolong the life of the road, provide a smoother surface and add durability
  • Improve safety and reduce the need for emergency and pothole repairs
  • New pavement markings and signs will increase lane and interchange visibility

Work Schedule

  • The ramp, barrier and resurfacing work will last approximately 10 months from early April to late October.
  • Lane and ramp closures will take place during the nights mostly when traffic impacts are lowest. 

Traffic Impacts

Full ramp closures and other lane closures from 10 p.m. Friday, April 25 through 6 a.m. Monday, April 28:

  • Eastbound and westbound 6th Avenue on-ramps will be closed to southbound I-25.  Detour: Take southbound Kalamath Street to the Santa Fe/Kalamath on-ramp to southbound I-25. 
  • Southbound I-25 off-ramp will be closed to Alameda Avenue.  Detour: Take the Santa Fe Drive Exit, proceed on South Santa Fe Drive, then turn left to cross Mississippi Avenue over the South Platte River and then turn left on North Santa Fe Drive to Alameda Avenue.
  • The auxiliary lane on southbound I-25 from 6th to Alameda avenues will be closed from 10 p.m. Friday, April 25 through 6 a.m. Monday, April 28.
  • The right lane on southbound I-25 from 6th to Alameda avenues will be closed overnight only, from 10 p.m. to 6 a.m. Friday, April 25, Saturday, April 26 and Sunday, April 27. The lane will be opened during the day. 
  • The closures are needed to replace the concrete barriers along southbound I-25 next to the South Platte River. The full weekend closures will complete the barrier work sooner, reducing three weeks of overnight closures and detours. Motorists should plan for delays on the detour routes.
  • The schedule above could change depending on weather and other factors. Go to COtrip.org for the latest lane closure information. 

Resurfacing work on I-25 begins in mid-May and lasts through October 2025:

  • Resurfacing work will begin once nighttime temperatures are consistently warm enough for asphalt paving.
  • From 9 p.m. to 6 a.m., Sundays - Thursdays: a single lane closure at 9 p.m. and then up to three lanes closed in each direction a few hours later on I-25 between Alameda and 44th avenues. All lanes will re-open before 6 a.m.
  • Ramps along I-25 where resurfacing operations occur will close for a few hours overnight. A detour route will be set up for each of the ramp closures.
  • While most of the lane and ramp closures will take place at night when traffic volumes are at their lowest, motorists should expect some delays. There could be weekend lane closures during the day and night as well.
  • The project team will adjust closure times depending on major events in the area.

Other work through January 2026:

  • There will be other work such as sign installations that will require some lane closures through January 2026. 
  • There could be possible weekend work, but most of the lane and ramp closures will occur Sunday through Thursday nights.

Work zone safety:

  • Motorists are urged to drive with extra caution through the work zone, watch for crews, heed the signs, do not speed and leave plenty of following distance.
  • Overhead electronic signs, other signage and traffic cones will be set up well in advance of the closures to warn motorists.
  • Lane closure information and real-time traffic condition are posted on cotrip.org.