North 83rd Street Reconstruction (Niwot Road to SH 119)

North 83rd Street Reconstruction (Niwot Road to SH 119)

Project Underway

Boulder County Transportation is reconstructing North 83rd between Niwot Road and the Diagonal Highway (SH 119). The project also includes the replacement of the Dry Creek #2 culvert and reconstruction of Lefthand Valley Grange Trailhead.

Construction will last through October 2017

  • Delays up-to 15 minutes from Sept. 5, through Sept. 29 between Neva Road and Diagonal Highway for paving.

Proposed Improvements:

  • Full reconstruction of 1-mile of North 83rd Street
    • Maintain current road width
    • Widen road by 4-feet between Niwot and Neva roads
  • Two new raised trail crossings
    • One at Niwot Loop Trail north of Niwot Road
    • One at Longmont-to-Boulder trail crossing south of SH 119
  • Reconstruction of the Lefthand Valley Grange Park parking lot (funded by Parks and Open Space Department)

Project Details & Designs

Construction-Ready Designs – Uploaded June 7, 2017 – This plan set has been broken down to make it easier to download

  • Pages 1 to 27 – Cover, introduction, notes, quantities, site plan, typical sections, tabulations, survey control, geology, and geometry
  • Pages 28 to 47 – Construction details and removals and resets
  • Pages 48 to 65 – Plans and Profiles
  • Pages 66 to 96 – Culvert details, storm drain, sewer, utilities, stormwater management, erosion control
  • Pages 97 to 111 – Signage and striping
  • Pages 112 to 162 – Traffic control during construction & detour plans, cross sections, trailhead plans, and easements

Closure of North 83rd – Summer 2017

North 83rd Street will need to be closed (24/7) for the month of August between Niwot and Neva roads in order to complete construction. View the detour plan.

Project Contacts

  • Andrew Barth – Communications – email or 303-441-1032
    • Contact Andrew to be added to the project email list

Contact Us

Transportation Department

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2525 13th Street
Boulder, CO 80304

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Boulder, CO 80306