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 CO 119/Diagonal Highway.
Starting at 9 p.m. on Tuesday, September 9, the Colorado Department of Transportation (CDOT) will close 2nd Avenue in Niwot at northbound CO 119/Diagonal Highway. This closure allows crews to complete median-widening for a future Bus Rapid Transit lane. Local access on 2nd Avenue will be maintained between Murray Street and the railroad tracks east of the highway. The closure is expected to last until the end of 2025. During this period, travelers are advised to use Niwot Road to access northbound CO 119/Diagonal Highway.
A second closure begins at 9 p.m. on Friday, September 12, when CDOT will close the Oxford Road median between northbound and southbound CO 119/Diagonal Highway. This closure affects all modes of transportation and is anticipated to continue until mid-October. Access through the Oxford Road median to northbound CO 119 will not be available during this time.
Crews will use this period to construct a raised bikeway crossing and widen the road for extended deceleration lanes. Following completion of work at Oxford Road, a full closure of the adjacent 83rd Street median is planned for several weeks; more information about that closure will be provided later.
Detour routes have been posted for both vehicles and cyclists:
– Westbound travelers should pass Oxford Road, continue 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.
Work schedules may change based on conditions.
By the year 2040, traffic along Diagonal Highway between Boulder and Longmont is projected to increase by about one-quarter compared with current levels. This growth could result in greater congestion, delays, emissions from vehicles, and possibly more accidents.
The purpose of the ongoing project is “to make traveling through the corridor safer for all modes and transit travel faster and more reliable,” according to CDOT officials. The project aims “to integrate with other active multimodal projects on the corridor” so community members can travel safely using their preferred mode.
Key goals include improving safety throughout the corridor; maximizing how many people can move through it; increasing operational efficiency at intersections; reducing transit travel times while boosting ridership; improving overall operational efficiency; and expanding opportunities for bicycle commuting by enhancing connectivity within pedestrian networks.
Specific improvements include new signage, updated striping patterns, improved signal timing at pedestrian crossings in signalized intersections such as Jay Road, 63rd Street, Colorado Highway 52, Niwot Road and Airport Road; adding a commuter bikeway with connection points between north- and south-bound directions including underpasses or overpasses at major intersections; physically reconfiguring Colorado Highway 52’s intersection for better safety as well as accommodating new Bus Rapid Transit stations alongside Boulder County’s Commuter Bikeway; modifying access points like Airport Road with CO 119 to reduce crashes while smoothing traffic flow.
During construction periods along CO 119/Diagonal Highway most existing configurations remain but expect various lane shifts or temporary closures with advance notice provided before major changes take place. Lane widths may be reduced along with speed limits during construction activity. Kraemer North America serves as general contractor for these efforts.
Project updates are available via phone (720-378-8083), email ([email protected]), or online at the official project website where weekly updates can also be requested.
