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Boulder County, Colo. - As construction continues on the CO 119 Safety, Mobility and Bikeway Project we have some exciting photos from the Colorado Department of Transportation showing work on the underpasses at CO 52, Niwot Road, and the bikeway connection to the Reservoir Trail/IBM Connector Trail.

Niwot Road Bikeway Underpass

Earlier this spring, the median section of Niwot Road was closed so the bikeway underpass could be installed. In coming months, a brand new and much improved bus station will be constructed around the underpass. The station will have parking, a bike-n-ride shelter, and Longmont and Boulder bound bus stops.

Aerial view of CO 119 and Niwot Road underpass construction of the bikeway as part of the CO 119 Safety, Mobility and Bikeway Project.

CO 119 and 52

The intersection at CO 119 and CO 52 is going to be improved for safety and to create a median for the bikeway. The CO 119 southbound lanes will be shifted closer to IBM Drive. This allowed the underpass at CO 52 to be constructed without any road closures because it was built to the side of the existing intersection.

Aerial view of construction of the bikeway underpass at CO 119 and CO 52.

Connection to Reservoir Trail/IBM Connector

The Diagonal Bikeway will connect to the Reservoir Trail/IBM Connector via a spur path. The bikeway has not yet been built, but the paved spur path is under construction now. When the bikeway is constructed it will be between the large green construction tanks and the Boulder bound lanes of CO 119 seen in the photo below.

Aerial view of construction of the spur trail that will connect the Diagonal Bikeway to the Reservoir Trail/IBM Connector.

Box Culverts at 55th St. and 63rd St.

The nine-mile-long construction project between Longmont and Boulder includes safety enhancements at numerous intersections, as well as bus rapid transit and a bikeway. In addition to these more visible upgrades, the project also incorporates essential but less glamorous infrastructure such as numerous concrete box culverts designed to manage the significant water flow that crosses the area.

Aerial view where the bikeway will cross over a concrete box culvert in near 55th Street.

Aerial view of concrete box culverts near 63rd Street.

More Project Information

View the interactive Diagonal Highway construction map showing the improvements. Zoom in to see the bus rapid transit stations and stops, the bikeway and the bike network connections, and zoom out to view the full nine miles of the project.

For more photos of the bikeway as it is being constructed check out the Diagonal Highway 119 Bikeway Design Project page  and the CDOT CO 119 Safety, Mobility & Bikeway page.

Stay Informed

Subscribe to CO 119 Diagonal Highway Safety, Mobility and Bikeway Project Construction Updates from CDOT.

Project Contacts

• CDOT phone: 720-378-8083
• CDOT email: co119safetyandmobility@gmail.com
• Boulder County phone: 303-441-4520
• Boulder County email: aphillips@bouldercounty.gov

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