Permanent traffic configuration shift planned for Airport Road and CO 119/Diagonal Highway intersection in mid-April

Boulder County — Beginning in mid-April, the Airport Road median at the Colorado Highway 119/Diagonal Highway intersection will permanently become a one-way, northbound road, leaving southbound travel in the median permanently closed to all modes of transportation.

Left turns from southbound CO 119 onto Airport Road and from southbound Airport Road onto northbound CO 119 will be eliminated. Travelers can use 83rd Street or alternate routes to access northbound CO 119.

The intersection will be transitioned to its final configuration with phased closures starting in mid-April and lasting approximately five months. Details of the phased closures will be released closer to the start of the intersection work.

The Colorado Department of Transportation is implementing this change as part of the CO 119 Safety, Mobility and Bikeway Improvements Project to address significant safety concerns at the CO 119/Diagonal Highway intersection:

• Data shows that 85% of crashes involving southbound Airport Road and CO 119 result in injury, with most occurring when vehicles attempt to turn left onto northbound CO 119
• Eliminating the southbound left turn onto northbound CO 119 (to Longmont) will reduce sideswipe and rear-end crashes, remove the need for a signal and bus queue jump lane at the current stop sign-controlled intersection, therefore improving overall corridor safety and mobility

What is the CO 119 Safety, Mobility and Bikeway Improvements 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, delays, tailpipe emissions and potentially more crashes.

The CO 119 Safety, Mobility and Bikeway Project is constructing safety, mobility and bikeway improvements to make traveling through the corridor safer for all modes of transportation, and to make 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 preferred mode(s) of transportation.

This project will:

• 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

Specific corridor improvements include:

• New signage, striping and improved signal timing at all pedestrian crossings at signalized intersections
• Signal timing adjustments at key intersections (Jay Road, 63rd Street, Colorado Highway 52, Niwot Road and Airport Road)
• Adding a commuter bikeway and several local connections between northbound and southbound CO 119, and underpasses or overpasses at major intersections for uninterrupted crossing
• Physically reconfiguring the CO 52 intersection to improve safety and to accommodate new Bus Rapid Transit (BRT) stations and the Diagonal Bikeway between the northbound and southbound travel lanes
• Changing access at Airport Road and CO 119 to reduce crashes and improve safety and traffic flow

During construction, CO 119/Diagonal Highway will largely remain configured as it currently operates, with various lane shifts and closures. Additional information will be provided prior to any major closures or detour routes throughout the project duration. In addition, lane and shoulder widths will be minimized. The speed limit will be reduced. Please pay attention and follow posted speed limits. Kraemer North America is the General Contractor for this project.

CO 119 Safety, Mobility and Bikeway Improvements Project Contact Information

• Project phone line – 720-378-8083
• Project email – [email protected]
• Project website – codot.gov/projects/co119-mobility
• Sign up for weekly project updates on the project website by following these five simple steps:
  • Visit the project website
  • Click on the "Stay Informed" box on the right side of the page
  • From there, scroll to the "Construction Updates & News Releases" section and select "Subscribe to Construction Updates"
  • Enter your email address, then select "Northeast Colorado" as the region, check "Front Range I-25 Corridor" and "CO 119 Safety & Mobility Improvements"
  • Scroll to the bottom and hit submit