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Highway 119 Bikeway Project

The Diagonal Highway 119 Bikeway Project

Boulder County is beginning the process of designing a paved off-street multi-use path along Colorado State Highway 119 (the Diagonal) between Longmont and Boulder. The purpose of the SH 119 Bikeway project is to optimize regional mobility between Longmont and Boulder by providing multimodal bicycle and pedestrian improvements that result in safer, more reliable, more comfortable and more appealing travel options.

Conceptual rendering of SH 119 Bikeway

Conceptual rendering of SH 119 Bikeway.

Boulder County is in the process of hiring a consultant to complete the design. It is anticipated that design will begin in early 2021 and take 18-24 months to complete. There will be multiple opportunities for input from the public and other stakeholders. View the SH 119 Bicycle and Pedestrian Connectivity Study Basis of Design Memo, July 12, 2019.

Completing a safe, reliable, comfortable and appealing bicycle connection between Boulder and Longmont will unlock the numerous benefits of cycling to anyone travelling this key regional corridor: health benefits, greatly reduced transportation costs, increased access to educational and employment opportunities, improved air quality, and fewer vehicles on the road.

This project is part of a larger, multi-agency vision for the SH 119 corridor, which includes Bus Rapid Transit (BRT), managed lanes, vehicle operational improvements, first and final mile improvements, and expansion of local transit networks. The SH 119 Bikeway will complement the vehicular highway corridor and the proposed Bus Rapid Transit improvements along SH 119 between Boulder and Longmont.

Construction of the SH 119 Bikeway will provide a safe, reliable, comfortable and appealing bicycle and pedestrian connection between Boulder and Longmont. The bikeway will be physically separated from the SH 119 roadway, and feature underpasses or protected signal phasing for pedestrians and bicyclists where the bikeway crosses major intersecting roads, greatly reducing if not eliminating conflicts with motor vehicles. Reducing conflicts will reduce bicycle vs motor vehicle and pedestrian vs motor vehicle crashes along this corridor, which currently has the second-most number of such crashes in unincorporated Boulder County. As a hard-surface facility, the SH 119 Bikeway will be plowed, which allows it to be used year-round, even during the snowiest months. The Bikeway will also connect to the SH 119 BRT stations, creating redundancy for commuters who commute by bike, transit or a combination of the two.

Project Documents

SH 119 Information and Resources

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Project Coordinator

Boulder County Community Planning & Permitting
Stacey Proctor, 303-441-1107

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