If Airport Road is part of your daily grind between Boulder and Longmont, start plotting a new route now. The Colorado Department of Transportation (CDOT) says crews will soon reconstruct the median at Airport Road as part of the CO 119 Safety, Mobility & Bikeway project, and that work will convert Airport Road to one-way northbound, permanently eliminating southbound vehicle access. While crews reconfigure the intersection, northbound drivers will be routed onto 83rd Street, bringing detours and lane closures across the Diagonal Highway between Boulder and Longmont. Officials estimate the conversion and related closures could last roughly five months and will hit day-to-day commutes throughout the corridor.
In a project update posted to the Colorado Department of Transportation on Feb. 18, CDOT said crews will begin reconstructing the Airport Road median into its final configuration and will permanently eliminate southbound travel at the intersection. The same update notes that once construction begins, northbound Airport Road traffic will use 83rd Street and that temporary closures tied to the conversion are expected to last about five months.
Why CDOT is changing Airport Road
According to the project FAQ from the Colorado Department of Transportation, engineers chose to eliminate certain left turns and through movements because those maneuvers create conflict points that can lead to sideswipe and rear-end crashes. CDOT also says removing the southbound vehicle lane frees up room for a new southbound bike lane and pedestrian upgrades while helping buses move more reliably along CO 119. As the FAQ puts it, "eliminating left turns prevents both sideswipe and rear-end crashes." In other words, fewer tricky turns, fewer crunching fenders.
How this fits into the CO 119 overhaul
The Airport Road conversion is just one piece of a corridor-wide package that adds a nine-mile separated Diagonal Bikeway, new underpasses at major intersections, and Bus Rapid Transit stops and park-and-rides to speed buses between Longmont and Boulder. As outlined by Boulder County, the multiagency program is designed to cut crashes and shorten transit times along the busy highway. Hoodline previously covered the project's construction kickoff in its report on the construction kickoff, signaling the start of this long-planned overhaul.
What drivers and cyclists should expect
Past travel advisories show CDOT leaning on temporary median closures and signed detours to keep people moving while crews work, and similar routing is planned during the Airport Road conversion. Drivers can expect to be directed to nearby medians and streets to complete left turns that used to happen directly at the intersection. According to a recent advisory from the Colorado Department of Transportation, cyclists and motorists should plan for intermittent full median closures, traffic pacing operations, and traffic shifts that may cause short holds or delays.
How to stay informed
Longmont and CDOT are urging commuters to plan alternate routes and to consider transit or carpooling while the conversion is underway. The City of Longmont's project page lists a project hotline at 720-378-8083 and an email address at [email protected] for construction questions. Transit riders are being asked to watch for service changes as BRT work continues and to sign up for project alerts through the agencies managing the CO 119 program, which publishes weekly construction updates and maps.
Expect the heaviest impacts during daytime work hours and during planned median closures. Businesses near Airport Road are expected to retain local access, but the way customers reach them will likely feel different while the median is rebuilt. We will keep following CDOT and local agencies for schedule changes and post further updates as traffic patterns continue to shift across the Diagonal Highway corridor.
