Foothills Parkway Bicycle and Pedestrian Underpass

Project Purpose and Scope

The existing bicycle and pedestrian bridge over Foothills Parkway south of Colorado Avenue connects neighborhoods east and west of Foothills Parkway to the University of Colorado Boulder, schools, parks and other bicycle and pedestrian paths, lanes and sidewalks. The bridge was constructed in 1978 and is at the end of its service life, requiring more frequent maintenance, and does not meet current Americans with Disabilities Act (ADA) guidelines and other bicycle facility design guidelines.

This project will provide an underpass crossing of Foothills Parkway for pedestrians and bicyclists that meets current guidelines and standards. The existing bridge will be removed. The project will include connections to adjacent bicycle and pedestrian paths, signage, bicycle parking, and replacement landscaping and trees.

Underpass Construction Project began Sept 23, 2019

The work is currently focused on creating the bicycle and pedestrian detour so it is in place prior to the overpass bridge removal which will occur later this fall. For up-to-date information on travel impacts from construction go to: www.boulderconezones.net.

See images to the right for the pedestrian and bike detour that will be in place and view a rendering of the to-be-constructed underpass from the west side of the project at Park East Park. Click images to enlarge.

Here is what to expect during the approximately one year construction period:

The current overpass bridge will be removed and a bicycle and pedestrian detour will be in place.
The underpass will be constructed in two phases.
Four lanes of Foothills Parkway will be open and shifted to the east side during the first phase.
Once the underpass work on the west side is complete, vehicles will be shifted to the west side of Foothills Parkway and underpass construction will take place on the east side.
There will be occasional off-peak lane closures.
Park East Park will remain open during construction.

Tree removal and relocations

The Transportation Division is working closely with the Forestry Division to minimize the number of trees needed to be removed for the construction of the underpass project. The tree removal process will take a phased approach which began in mid-February 2019 and finishing in August 2020 when construction is anticipated to be completed. The work began in mid-February 2019 to minimize or eliminate impacts to nesting raptors during their upcoming nesting season.

The city will replant an equal number of trees around the city to replace those removed. Sixteen trees that have been removed were reloacted to Foothills Golf Course, Park East Park and the east end of the Civic Area, near the recently improved Arapahoe Underpass.

View the flyer on the tree removals. If you have questions, please call 303-441-3200.

Review process

The project has been reviewed through the city’s Community and Environmental Assessment Process (CEAP). The CEAP assesses potential impacts of a public project to inform the selection and refinement of a preferred project alternative.

Following the consideration of community feedback and technical evaluation, the recommended underpass alternative is 1b. Participants in the public process generally favored this alternative. Alternative 1b will:

Improve mobility for all ages and abilities
Maintain the neighborhood access for the various bicycle and pedestrian travel patterns
Provide a more direct crossing connection compared to other alternatives (does not require entry ramp loops and steep grades)
Provide access to the Wellman Ditch company for maintenance, which is also an improvement from existing conditions
Be constructed within the project budget and with a shorter construction duration compared to the other alternatives

1b also supports other factors such as directness of travel and connections to natural features. The new underpass will have a design life of 75 years and will meet current accessibility and bike facility design standards with less-steep slopes.

At the June 11, 2018, Transportation Advisory Board (TAB) meeting the Board held a public hearing and recommended (4-0) approval of the CEAP and the preferred alternative. The CEAP was forwarded to City Council for potential call-up by July 17, 2018 and the City Council did not call-up the CEAP. The project's preferred alternative will move forward into preliminary and final design. The project is anticipated to begin construction in 2019 and take one year to complete.

Learn more about the recommended alternative 1b and matrix evaluation for all alternatives .