CO 119 Boulder Canyon Improvements

Martin Luther King, Jr. Day

There will be no full closure on Monday, Jan. 20 to recognize Martin Luther King, Jr. Day. Crews will be onsite working inside single-lane closures. 

Dec. 2 CO 119 Boulder Canyon Town Hall Recap

On Monday, Dec. 2 CO 119 Boulder Canyon Project Officials held a town hall in Nederland to discuss schedule updates. Below are the highlights: 

  • The project schedule has been accelerated by nine months by eliminating two rock cuts. The completion date has moved from Sept. 2021 to Dec. 2020. 
  • The overall timeline of the daily closures has been reduced by seven months – ending in February instead of September. 
  • CDOT has installed a temporary Wi-Fi service to address communication concerns in signaled areas. 
  • Resident passes are available through the Sheriff's office for residents to access the Fourmile Canyon detour during daily closures. 

With the elimination of rock cuts four and five, what improvements are lost? 

Rock cuts four and five were intended to make space for a 13-feet rock catch ditch with a 6ft shoulder. Following this redesign, these ditches will be about 5-8-feet deep, and the roadway will move closer to the river. This adjustment will require more rock armoring along the river. Sight distance will be improved, and rock will still be reinforced. 

With the elimination of rock cuts four & five, will the roadway be moved onto bedrock?

Rock cuts 4 and 5 were designed to install rock catching ditches, not necessarily to move the roadway. The design has been adjusted to reduce the depth of the rock ditches, and use more rock armoring to protect the roadway. 

When will the single-lane closures be complete? 

There will be single-lane closures through December 2020. Inclement weather could prevent crews from completing paving before winter, in which case paving would be completed between May-June 2021. 

Is there any chance that the blast zone will open to two lanes earlier? 

The project team was hopeful that work would allow for two -ane traffic through the blast zone this winter; however, some unexpected changes to the bridgework will prevent that. The single -ane area will shorten, as work is completed. 

Can sight distance be improved at the signal area? 

The length of the signal lane will continue to decrease, meaning that sight distance will increase. 

Can you keep the blast area properly paved and potholes patched in between blasts?

With the winter conditions, it is difficult for CDOT to acquire asphalt, however, the project will do it’s best to maintain the roadway in between blasts. 

What are long-term options for cell service and emergency phones in the canyon?

CDOT will look into emergency call boxes; however, this type of communications work is outside of CDOT’s typical jurisdiction. DOT’s ITS group has communicated and extensively brainstormed with AT&T and Verizon, but there are no plans for either provider to install permanent service. 

How do residents connect to CDOT’s temporary Wi-Fi service? 

To use the WIFI calling, start by enabling Wi-Fi calling in your phone settings. Then connect to CDOT_PUBLIC_WIFI. Users will need to agree to drive distraction-free and click "OK". Once this is complete, calls can be made and received. You must be stationary to connect. Please note that the Wi-Fi signal is limited. CDOT is researching ways to increase the signal. 

What is rock armoring? 

Crews will be installing large boulders in between the river and the roadway slope. This rock barrier will protect the highway from erosion and washout during flood events. 

Will new delineators be installed throughout the canyon?

Delineators will be installed throughout the canyon as part of the safety improvements for the project. 

What is a shoefly?

A shoefly is a temporary roadway detour around the work area.

Can the project accelerate the trail work?

The project is looking at ways to accelerate the Boulder Creek trail construction. There will be a handful of 4-hour closures in the spring to accelerate blasting work for the trail. 

Will there be blasting at the Alps Inn for the Boulder Creek Trail construction? 

Yes, one of the 4-hour closures will be used to blast the rocky knob just east of the Alps Inn. The project will coordinate with the owners of the Alps Inn during this time. 

How wide will the new bike trail be? 

The Boulder Creek Trail will be 12-feet wide in most areas. 

Will all rock slopes be reinforced? 

Yes, all of the rock-cut areas will be reinforced and covered with mesh designed to guide loose boulders into the rock catch ditches. 

Where can I find more information on the traction laws?

If weather conditions require, CDOT can implement Passenger Vehicle Traction and Chain laws. Motorists will be alerted to an active Traction Law or Chain Law by highway signage, or traffic/roadway condition alerts.

During an active Traction Law (also known as a Code 15), motorists must have either snow tires, tires with the mud/snow (M+S) designation, or a four-wheel/all-wheel-drive vehicle. Starting Aug. 2, 2019, the legislation updated requirements for drivers using state highways during winter months. Specifically, it changed the required minimum tire tread for vehicles on snowy roads to 3/16 of an inch. You can also install chains or an alternative traction device (like AutoSock) to be in compliance with the law if your tires aren't adequate.

More information is available on CDOT’s website

Is the new barrier in the blast area contributing to icy conditions due to its lack of drainage? 

CDOT is using this season to evaluate the barrier and will install more drainage if needed. Typically in this area, the water drains away from the barrier. 

Work this Week

Monday - Friday there will be 4-hour single-lane impacts west of the blast zone while crews excavate under the highway to build a wall. Please plan for additional delays. 

24/7 Ongoing Impacts

  • Rock blasting and excavation activities will result in a full closure of Colorado Highway 119 from MP 39-40 between the hours of 10 a.m. to 2 p.m. every Monday through Thursday. Motorists entering the canyon from Nederland will be stopped at 9:45 a.m.
  • Culvert installation will impact MP 36, and rock hauling will impact MP 40.
  • Motorists will be guided around the single lane closures with traffic control flaggers.
  • Three traffic signal zones will remain in place near MP 32, MP 38 and near MP 39, 24-hours a day, 7 days a week, to preserve the work areas.  

Up to 40-minute delays are expected through the canyon during work hours. Speed limits are reduced to 25 miles per hour in the construction zones. The work is weather-dependent, and the schedule may change. 
Please plan additional time to travel through the construction zones or to use the alternate routes of Colorado Highway 72 or Lefthand Canyon Drive during the full road closure. 

Trail Closure
The FULL CLOSURE of the Boulder Canyon trail at MP 40 where it crosses under CO 119, will be extending a mile and a half to the east, preventing through access from Boulder to the Four Mile trailhead. Crews will rehabilitate the highway structure and install underground rock protection for the next three months.  Eastbound cyclists will need to merge with CO 119 traffic through this area. Westbound cycling will be closed through the work area, but open beyond the project limits. 

Creek Closure
The Boulder Canyon Creek will be closed for use from the canyon mouth in Boulder to the Fourmile Canyon trailhead, Monday - Thursday, 10 a.m. – 2 p.m. 

ALERT: Four Mile Resident Permits  

Residential permits remain available for residents who live in areas above the Fourmile/Boulder Canyon intersection and need access to Fourmile Canyon and Poorman Road during the Boulder Canyon Blasting Closures. This includes Sugarloaf, Magnolia, and upper Boulder Canyon residents. Residents living in Fourmile Canyon do not need a pass.

 To obtain a pass, please contact:

Kelly Lucy with the Boulder County Sheriff’s Office at 303-877-1720 (Monday – Wednesday), or at [email protected] (anytime). You must provide your full name, phone number, house address, mailing address, and the license plate number for each vehicle needing a pass. Passes will be sent by U.S. mail to the mailing address supplied.

CDOT Provides Temporary Wifi Calling to Boulder Canyon

Following requests from the local communities to install cell service throughout Boulder Canyon, CDOT has explored a variety of options. Unfortunately, installing service through Verizon or AT&T was not an option. However, CDOT has installed temporary public wifi near the Fourmile Intersection and the east portal of the tunnel. This wifi will allow community members to not only make calls using Wifi calling, but also communicate using several different applications such as Facebook Messenger, SnapChat, Google Hangout, etc. The wifi is limited, but has been tested and proven to work throughout these areas.

SH119_Public WiFi_CDOT

To use the wifi calling, start by enabling Wifi calling in your phone settings. Then connect to CDOT_PUBLIC_WIFI. Users will need to agree to drive distraction-free and click "ok". Once this is complete, calls can be made and received.

Do not drive distracted.

CDOT does not encourage drivers to make calls or use any apps while driving. Distracted driving is the act of driving while engaged in anything—texting, looking after children or pets, talking on the phone or to a passenger, watching videos, eating, or reading—that takes a driver's focus away from the road. Distracted drivers cause an average 43 crashes each day in Colorado. In 2018, there were 15,673 crashes in Colorado that involved a distracted driver.

Finally, CDOT used 100% solar to power the WiFi system. This system will function throughout the night and several days without sun. This wifi will only be available throughout the duration of the project.

Project Facts

  • Cost: $31 Million
  • Contractor: Zak Dirt
  • Timeline: Winter 2019 - Summer 2020
  • Location: CO 119 between Boulder and Nederland
  • Alternate Route During Construction: CO 72 is a recommended detour. Learn more about the CO 72 Coal Creek Canyon project.

In March 2019, crews began repairing a 15-mile stretch of Colorado Highway 119, between Boulder and Nederland, which was damaged during flooding in 2013.

Work includes:

  • resurfacing 13 miles of highway, and entirely replacing two miles of highway;
  • building concrete islands to improve the roundabout in Nederland;
  • installing new highway directional and safety signage;
  • replacing multiple pipes conveying stormwater drainage under the highway;
  • scaling rock in selected areas to reduce rockfalls on the highway;
  • repairing soft shoulder areas immediately adjacent the highway;
  • replacing 29,000 linear feet of concrete or metal guardrail;
  • removing and replacing materials placed during emergency repairs;
  • excavating areas where the slope had failed in the storm;
  • redesigning and widening specific sections of the roadway;
  • reconstructing embankments; and
  • re-establishing native grass seed and erosion control to slopes that were disturbed during emergency recovery work.

Boulder County Trail Improvements

The project, in partnership with Boulder County, will extend and reinforce sections of the Boulder Canyon Trail. The 10-foot-wide, multi-use trail will be extended from Four Mile Canyon to Chapman Drive—adding two new bike-friendly tunnels under the highway and approximately 3500 feet of length to the trail.

Project Work Hours:

  • 7 a.m. - 7 p.m., Monday - Friday
  • Rock-blasting work hours: 10 a.m. - 2 p.m., Monday – Thursday 
  • No night or weekend work is planned. However, some work zones will remain closed to preserve the work area.

Travel Impacts & Delays

Various delays from single lane & full road closures are expected throughout the project.  Motorist are strongly encouraging everyone to plan ahead to give yourselves enough time to reach your destination.

  • Expect full highway closures for rock blasting and excavation, with four-hour complete closures.
  • Expect various long-term single-lane closures managed by temporary traffic signals, and various short-term single-lane closures managed by flagging.
  • Full Canyon Closures Monday through Thursday and 40-Minute Delays.
  • Speed limits will be reduced to 25 mph in the work zones. Expect several stops through the corridor.  
  • A permit-load restriction will be in effect.

Boulder Canyon Trail Impacts

  • April – August 2019
    • Crews will close the trail and parking areas adjacent to the trail (near mile point 40) when rock blasting is needed.
    • The trail could be impacted four times a week for nine hours at a time to allow for safe rock-blasting activities.
    • No weekend or holiday work is planned.
  • August - December 2019
    • The trail will be closed below the Boulder Canyon Trailhead at all times, including weekends and holidays.
    • Crews will place signage along the trail, at the opening of the canyon near Boulder City limits.

SH 119 Boulder Canyon Public Meeting Presentation

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