Closures & Construction

Construction-Related Travel Impacts

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 with Travel Impacts

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.

  • Magnolia Road Guardrail Replacement – Lane reductions & 1-day road closure
    • Magnolia Road reduced to one-lane near Boulder Canyon Drive – 24-hours a day, seven days a week
      • Monday, Sept. 18 to Friday, Oct. 20
      • Traffic signal will be used to move travelers safely around work zone
    • 1-Day FULL CLOSURE OF east Magnolia Road at work site – Thursday, Sept. 28, 2017 – 9 a.m. to 5 p.m.
      • Date is weather dependent and could change if rain or snow is forecast
      • 9 a.m. to 9 p.m.
      • Both cars and bikes will be prohibited from passing through the work zone
      • Closure is necessary for delivery and pumping of concrete used to secure guardrail posts
      • Detour to west Magnolia and CO Highway 119 south of Nederland
    • Project Contact – Andrew Barth – 303-441-1032
  • 95th Street (Valmont and Isabelle) Intersections and Resurfacing Project – Daytime/Weekday closures – some Saturday work will be completed using flaggers to control traffic (no full closures on weekends)
    • 95th Street CLOSED from just north of Valmont Road to the Lafayette city limits
      • For both cars and bikes
    • 8 a.m. to 4:30 p.m., Monday through Friday
    • Isabelle Road will be open to local residential traffic only between Hwy 287 and 95th Street
    • Valmont Road will be open to local residential traffic only between 75th Street and 95th Street
    • Anticipated end date = November 2017
    • Project Contact – Andrew Barth – 303-441-1032
  • East Arapahoe Road resurfacing project – Lane Closures – Aug. 7 through October 2017
    • Resurfacing eastern portion of Arapahoe Road between Lakota Ranch Road and Town of Erie limits
    • Working hours = 8 a.m. to 4:30 p.m. – Monday through Friday
    • Lane closures in place during working hours
    • Cyclists will merge with traffic
    • Project Contact – Andrew Barth – 303-441-1032
  • North 83rd Street (Niwot) culvert replacement and roadway resurfacing project – Delays and road & trail closures
    • Project Area = Niwot Road to Diagonal Highway/SH 119
    • Lane reductions – 8 a.m. to 4:30 p.m.
    • Sept. 5 to Sept. 29 – Single-lane closures for paving operations
      • Neva Road to Diagonal/Hwy 119
      • 9 a.m. to 4 p.m. – Monday through Friday
    • Project expected to last until early November
    • Project Website
    • Project Contact – Andrew Barth – 303-441-103
  • James Canyon Drive Flood Recovery Permanent Repairs
    • Expect travel delays between Lefthand Canyon and Jamestown
      • Week of Sept. 25, 2017 – Delays ranging between 15 and 25 minutes
    • Single Lane Closures – Multiple locations – 24 hours a day/7 days a week
    • Road will remain open to cyclists
      • Expect heavy truck traffic and rough travel conditions in short stretches
    • December 2018 estimated completion date – weather permitting
    • Project Contact – Andrew Barth – 303-441-1032
  • Wagonwheel Gap Road Flood Recovery Project – Lane closures & Travel Delays
    • Expect single-lane closures and travel delays ranging up to 15-minutes
    • Longer delays may be necessary at times – visit the project website for detailed information
    • Bow Mountain Drive closed at Wagonwheel Gap Road while a new bridge is constructed
    • Project Contact – Andrew Barth – 303-441-1032
  • East County Line Road single-lane closures at Hwy 52 – PROJECT WILL RESTART END OF SEPTEMBER 2017
    • Expect infrequent single-lane closures on East County Line Road at Hwy 52
    • Lane closures set up on an as-needed basis when working on the surface and guardrail of the bridge over east Boulder Creek
    • 8:30 a.m. to 4 p.m. – Monday through Friday
    • Crews working to repair damages sustained during the Sept. 2013 flood event
    • Project Contact – Andrew Barth – 303-441-1032

Cycling – Projects impacting cycling

View the Cycling Closure Map .

Other Non-County Construction and Events resulting in travel restrictions

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Transportation Department

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2525 13th Street
Boulder, CO 80304

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Boulder, CO 80306