CO 119 Safety, Mobility & Bikeway | Construction Phase
About the Project:
By the year 2040, the Diagonal Highway between Boulder and Longmont is expected to see a 25% increase in vehicular traffic. Increased traffic can result in more congestion, delay, tailpipe emissions, and potentially more crashes. The Colorado Department of Transportation (CDOT), the Regional Transportation District (RTD), and Boulder County are taking action to mitigate these outcomes and expand transportation options beyond private automobiles.
The CO 119 Safety, Mobility and Bikeway Project is constructing improvements to make traveling through the corridor safer for all modes and transit travel faster and more reliable. The project is designed to integrate with other active multimodal projects on the corridor to ensure community members can safely and reliably travel throughout the corridor using their mode(s) of choice.
Project Facts
- Program Cost: $165 million
- Contractor: Kraemer North America
- Timeline: Fall 2024 to Spring 2027
- Location: Colorado Highway 119 (CO 119) between Boulder and Longmont
- Nearest Town/City: Between Boulder and Longmont
- Mile Point(s): 44.5 to 54.5
- County: Boulder
Funding has been secured for implementation of the project and a Construction Manager/General Contractor (CM/GC delivery method) will be used to build the project with construction scheduled to start in 2024.
CDOT, RTD, and Boulder County are excited to share details about the improvements coming to CO 119 that will make traveling through the corridor safer for all modes, as well as faster and more reliable for public transit.
Watch the online presentation videos below to learn more about the safety, mobility, and bikeway improvements. Email [email protected] if you wish to receive this presentation in Spanish.
General CO 119 Safety, Mobility & Bikeway Project Updates
Project Area
Key features include:
- Bus Rapid Transit (BRT) Stations: Marked with red bus icons along CO 119.
- Park-n-Ride Locations: Indicated with blue "P" icons at various stations.
- Operational & Safety Improvements: Shown with green intersection icons.
- Bus Queue Bypass Lanes: Denoted with a gray bus with a green arrow.
Proposed RTD BRT Routes:
- Blue Line: Proposed with a 30-minute frequency between Boulder and Longmont, bi-directionally, weekdays and Saturdays: 6 a.m. to 9 p.m. and Sundays 7 a.m. to 7 p.m. Hourly service frequency earlier and later are also proposed to be provided.
- Orange Line: Proposed with a 30-minute frequency between Boulder and Longmont, bi-directionally, weekdays in the peaks only (6 a.m. to 10 a.m. and 2:30 p.m. to 6 p.m.)
- Routings of these two patterns will slightly vary within Boulder and Longmont.
Additional features:
- Intersection reconfiguration at Mineral Road.
- Northern and Southern Project Limits marked in Longmont and Boulder respectively.
Major roads and highways are also labeled, including Airport Road, Hover Street, Niwot Road, Mineral Road, Lookout Road, Jay Road, CO 52, CO 119, and CO 157.
Project Improvements
- New signage, striping, and improved signal timing at all pedestrian crossings at signalized intersections.
- Signal timing adjustments at key intersections (Jay Road, 63rd Street, CO 52, Niwot Road, and Airport Road).
- Physically reconfiguring the CO 52 intersection to improve safety and to accommodate new Bus Rapid Transit (BRT) stations and Boulder County’s Commuter Bikeway between the northbound and southbound travel lanes.
- Changing access at Airport Road and CO 119 to reduce crashes and to improve safety and traffic flow.
- A list of all stops associated with the proposed BRT service is available here.
Project Goals
- Improve safety in the whole corridor
- Maximize the number of people able to move through the corridor
- Maximize intersection operational efficiency
- Improve transit travel times and increase ridership
- Maximize corridor-wide operational efficiency
- Increase opportunities for bicycle commuting and connectivity to the bicycle and pedestrian network.
Project Benefits
- Vehicles can move through the corridor faster, with shorter wait times at traffic lights, resulting in less fender benders and crashes
- Traveling the corridor by bus will take about half the time it currently does
- More frequent bus service supports greater travel flexibility
- Safer and more comfortable experience accessing the corridor on foot
- Integration between Bus Rapid Transit, Park-n-Rides, pedestrian crossings, and Boulder County’s Commuter Bikeway enables commuters to switch travel modes safely and reliably
Next Steps and Project Schedule
- Reviewing and optimizing the proposed design.
- Planning out the potential phasing of construction.
- Determining how the design will be packaged for construction.
- Establishing a schedule for construction.
- Starting construction in 2024.
Traffic Impacts:
Monday, Oct. 21, 2024 to Saturday, Oct. 26, 9 p.m. to 5 a.m., there will be overnight various northbound and southbound CO 119/Diagonal Highway single lane closures at Niwot Road to set barrier and shift traffic.
Beginning at 7 a.m. on Monday, Oct. 28, crews will close 71st Street, between Monarch Road and CO 119/Diagonal Highway, to all modes of transportation. This seven-month closure will last through May 2025.
Motorists using 71st Street to get to CO 119/Diagonal Highway will follow posted detour signs for alternate access:
- Those traveling southbound on 71st Street should continue east on Monarch Road for access to southbound CO 119
Businesses can access their properties by using Monarch Road at CO 119/Diagonal Highway. This closure is required for crews to safely tie in new southbound CO 119 to the existing CO 119 infrastructure
Niwot Road between northbound and southbound CO 119/Diagonal Highway, in the median, will close to all modes of transportation overnight from 9 p.m. Monday, Oct. 28, to 5 a.m. Tuesday, Oct. 29.
- Eastbound Niwot Road traffic will take southbound CO 119 to eastbound Colorado Highway 52 to northbound 79th Street
- Westbound Niwot Road traffic will take northbound CO 119 to Airport Road back to southbound CO 119
This closure is required for crews to shift traffic to the north on Niwot Road and move it into phase one for constructing the underpass.
Beginning at 9 p.m. Friday, Nov. 1 to 5 a.m. Monday, Nov. 4, there will be a full closure of eastbound Jay Road at CO 119/Diagonal Highway to all modes of transportation. Westbound Jay Road will remain open. This closure is required for crews to begin waterline installation work. There is a separate detour for cyclists.
- Eastbound Jay Road traffic will travel south on CO 119, keep right at the CO 157 intersection to shift to northbound CO 119 and to return to Jay Road
- Eastbound cyclists will travel south on 47th Street, north on CO 119, east on Independence Road and head north on 57th Street to return to Jay Road
