Boulder Canyon Drive/CO 119 is undergoing construction to repair 2013 flood damage. The improvement project will also resurface and widen the road. As part of this project, the Boulder Canyon Trail will be extended to Chapman Drive with two additional bike underpasses. There will be road delays during construction with one-way traffic stoplights. The project began in March 2019 and is expected to be completed by summer 2020.

When crews are blasting rock, both Boulder Canyon Drive and the Boulder Canyon Trail will be closed. Typically, these closures will happen 2 days a week during two 2 hour shifts. Chapman Drive will not be accessible from Boulder Canyon. Because Fourmile Canyon is still closed to recreational bike traffic 8:00-4:30 M-F, both the main Betasso trailhead and the Fourmile trailhead will not be accessible by bike.

Update: 6/18/2019 – There is no cycling access westbound from Boulder to Nederland. The area is so congested right now with shoulder closures, lane closures, and work equipment that it would not be safe for cyclists or motorists. There is eastbound cycling from Nederland to Boulder, when the road is open.

 What this means for riding Betasso:

  • You cannot access Betasso via bike from Boulder M-F 8:00 a.m. – 4:30 p.m. Fourmile Canyon Rd is also closed to recreational cyclists during this time.
  • Outside of the hours of M-F 8:00 a.m. – 4:30 p.m. you may only ride to Betasso via Fourmile Canyon Rd and the Fourmile Link trail.
  • You may ride back to Boulder either via the Betasso Link trail or Fourmile Link Trail.
  • Weekly Boulder Canyon Drive and Boulder Canyon Trail closures are still in effect, closure days and hours change every week.
  • When Boulder Canyon Drive is not closed to car traffic, you can drive and park at the main Betasso trailhead, the Fourmile trailhead (as long as there are parking spots at the designated pullout) or at the bottom of the Betasso Link trail.

You can subscribe to text alerts about the canyon closures by texting CO119 to 21000 or learn more information about the project and see this week’s closures.