Two road closures are scheduled to begin the week of September 8 as part of ongoing work on the Colorado Highway 119 Safety, Mobility and Bikeway Improvements Project. The closures will affect 2nd Avenue in Niwot and the Oxford Road median between northbound and southbound lanes of CO 119/Diagonal Highway.
The Colorado Department of Transportation (CDOT) will start a full closure of 2nd Avenue in Niwot at northbound CO 119/Diagonal Highway at 9 p.m. on Tuesday, September 9. This closure is needed for crews to complete median-widening work for a future Bus Rapid Transit lane. Local access on 2nd Avenue will be maintained between Murray Street and the railroad tracks just east of the highway. The closure is expected to last until the end of 2025, with travelers advised to use Niwot Road to reach northbound CO 119/Diagonal Highway.
A second closure will begin at 9 p.m. on Friday, September 12, when CDOT closes the Oxford Road median between northbound and southbound CO 119/Diagonal Highway. This closure, which affects all modes of transportation, is set to remain in place until mid-October. Access to northbound CO 119 through this median will not be possible during this period.
While work continues at Oxford Road, crews will construct a raised bikeway crossing and widen the road to extend deceleration lanes. After this phase, a full closure of the adjacent 83rd Street median is planned for several weeks; more details about that closure will be provided later.
Travelers are asked to follow posted detour routes for alternate access. There is also a designated cyclist detour available.
Westbound travelers should continue past Oxford Road on northbound CO 119, turn left onto Airport Road median, then left onto southbound CO 119 before turning right onto Oxford Road. Eastbound travelers and cyclists should turn right onto southbound CO 119/Diagonal Highway, left onto Niwot Road median, then left again for access to northbound CO 119.
Schedules may change based on conditions.
According to projections by transportation planners, traffic volumes along Diagonal Highway between Boulder and Longmont could rise by about one quarter by the year 2040. Increased traffic could lead to greater congestion, longer delays, higher emissions from vehicles, and potentially more crashes.
The goal of the current project is “constructing safety, mobility and bikeway improvements to make traveling through the corridor safer for all modes and transit travel faster and more reliable.” According to CDOT: “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 objectives include improving safety throughout the corridor; increasing how many people can move through it; maximizing operational efficiency at intersections; reducing transit travel times while increasing ridership; enhancing overall efficiency; and expanding options for bicycle commuting as well as connectivity with pedestrian networks.
Specific improvements include new signage and striping at pedestrian crossings with better signal timing at key intersections such as Jay Road, 63rd Street, Colorado Highway 52, Niwot Road and Airport Road; construction of a commuter bikeway with local connection points plus underpasses or overpasses at major intersections; reconfiguration of Colorado Highway 52 intersection for improved safety including new Bus Rapid Transit stations; changes in access at Airport Road intended both to reduce crashes and improve flow.
During construction most aspects of how traffic operates along CO 119/Diagonal Highway will remain unchanged except where lane shifts or closures occur temporarily. Lane widths may be reduced during some phases along with lower speed limits being enforced throughout affected segments.
Kraemer North America serves as general contractor for this project.
For updates or questions regarding construction activities residents can call (720) 378-8083 or email [email protected]. More information including weekly updates can be found online at codot.gov/projects/co119-mobility.
“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 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.”
“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 & pedestrian network.”
