Closures & Construction

Boulder County Transportation manages the construction projects for roads, bridges, pathways, drainage improvements and trails. The projects listed on this page are related to flood recovery and regularly scheduled roadway maintenance.

County Road Projects

The following county roadway projects result in travel impacts to both motorists and cyclists. All dates and times listed are weather dependent. Please visit this page regularly for updates on the projects listed and for information on new projects. View the Roadway Closure Map to see these projects and where roads/bridges remain closed due to the 2013 flood. 

  • Upper Lefthand Canyon patching and roadway resurfacing project starts Aug. 17 lasts through September
    • Mile Marker 12 to Mile Marker 16
    • 8 a.m. to 4:30 p.m. - Monday through Friday
    • Work will require closing one lane of traffic - flaggers will be used to move vehicles through zone
    • Project Contact - Andrew Barth - 303-441-1032 or email 
  • Lee Hill Road Culvert Replacement Project - August to early September 
    • Road maintenance replacing culverts in advance of larger road & guardrail repair project
    • Lee Hill reduced to one lane of alternating traffic between Olde Stage and Deer Trail
    • 7 a.m. to 4 p.m. - Monday through Thursday
    • Project Contact - Andrew Barth - 303-441-1032 or email 
  • 2015 Community Use Road Reconditioning in County Subdivisions - - Detours will be established
    • Work will commence June 1 and will be complete in September - weather permitting
    • Roadway resurfacing and rehabilitation of of concrete curbs and pedestrian crossings/sidewalk ramps
      • Longview Drive in Niwot
      • COMPLETE - Idylwild Trail, Clubhouse Road and Carter Trail in Gunbarrel
    • Travel delays and parking restrictions can be expected 8 a.m. to 4:30 p.m. - Monday through Friday
    • Signage will be placed in advance of work to inform residents, and traffic control personnel will assist with moving travelers around work zones
    • Project Contact - Andrew Barth - 303-441-1032 or email 

Cycling - Projects impacting cycling

The following roads have travel restrictions for cyclists only due to safety concerns with the road surface and heavy construction traffic stemming from the 2013 flood event. Please respect the restrictions. Boulder County and CDOT are working to reopen these areas to cyclists as soon as possible. View the  Cycling Closure Map . (NOTE - The map is being updated so some closures and restrictions may not appear.)

Other Non-County Construction and Events resulting in travel restrictions

  • CDOT bridge rehabilitation
    • 3 bridges in Boulder County
      • US 287 and Coal Creek - Lafayette
      • Foothills Parkway and Diagonal - Boulder
      • Diagonal Highway over Four Mile Canyon Creek - Boulder
    • June 22 through Oct. 2015
    • Night Work - 7 p.m. to 5:30 a.m.
    • Expect lane closures, lane shifts and reduced speeds in work zones
    • Info = Project Email - Phone = 1-888-759-6197 (option 5)
  • CDOT Wetland Mitigation on east Valmont Road between 55th and 61st streets
    • CDOT creating new wetland area to mitigate wetland loss associated with US 36 Express Lane Project (more info below)
    • Expect work and travel delays from 7 a.m. to 7 p.m. - Monday through Friday
    • Info = 303-991-4591 or email
  • 2015 Special Events taking place throughout Boulder County
  • US 36 Express Lanes Project - Boulder to Denver - Learn more about lane and ramp closures and other travel restrictions - Work being completed by CDOT 

  • Learn about road closures in the City of Boulder at

 Related Links