The Colorado Department of Transportation announced on April 9 that the Airport Road median at CO 119/Diagonal Highway will be converted into a permanent, one-way northbound road beginning Monday, April 13. Southbound travel through the median will be permanently prohibited starting at approximately 3 p.m. on that day.
This change is part of ongoing efforts to improve safety and mobility in the area. The project aims to address significant safety concerns at the intersection, where data shows that most crashes involving southbound Airport Road result in injury and occur when vehicles attempt left turns onto northbound CO 119.
On April 13 from 7 a.m. to 3 p.m., there will be a full closure of the Airport Road median between northbound and southbound CO 119/Diagonal Highway for all modes of transportation as crews prepare for safety improvements. During this time, detours will redirect eastbound travelers via southbound CO 119 and westbound travelers via northbound CO 119, with both RTD bus stops at the intersection temporarily closed for pedestrian safety.
After reopening at approximately 3 p.m., traffic patterns will shift: only northbound movement through the median will be allowed as Phase One of construction begins, lasting about two months. This phase includes right lane closures on Airport Road just north of CO 119/Diagonal Highway and reduced lanes within the median itself. Pedestrians and cyclists are directed to use crosswalks on the east side during this period.
According to the official website, by year 2040 vehicular traffic along Diagonal Highway between Boulder and Longmont is expected to increase by about a quarter, which could lead to more congestion and potential crashes if not addressed. The current project is designed not only to improve corridor-wide operational efficiency but also enhance transit reliability, bicycle connectivity, and overall intersection safety.
The Colorado Department of Transportation oversees transportation infrastructure across Colorado according to its official website. Shoshana Lew serves as executive director according to department information. The agency builds and maintains highways while supporting aviation and transit projects statewide as stated online.
More information about detours or future changes can be found on the project website or by contacting project representatives directly.
