Diagonal Reconstruction – 28th to Foothills Parkway, Boulder, CO

LORIS recently finalized construction documents for reconstruction of this ¾ mile long section of the Diagonal Highway (SH119) with a concrete pavement. The entire roadway section was modified and drainage improvements provided. Pedestrian and dedicated bicycle facilities are also provided. Since this is the major northeastern gateway into Boulder, landscaping and public art are incorporated into the design.

In addition to the roadway and drainage work, multiple pedestrian, bicycle and transit-oriented improvements were incorporated into the design. One-way, detached, bike-only facilities (cycletrack), were included in lieu of typical on-street bike lanes. A 10-foot-wide, multi-use path was also included on the south side of the highway; and a bike-sharing “B-Cycle” station was included along with a “Bus-Then-Bike Shelter” for transit stations.
Sustainable design was an important portion of this project. LORIS and City staff implemented a full depth reclamation process into the design so that the existing asphalt roadway could be reused as the new base material for the proposed concrete road. Rain garden runoff filtration areas were also incorporated to satisfy both the City’s and CDOT MS4 requirements.
LORIS worked with two artists to first incorporate their design into the streetscape and then provide structural design for the large art pieces. The western installation includes overlapping octagonal, weathering steel planter beds that ground a 25-foot-tall illuminated tower. The eastern installation consists of a cluster of illuminated glass and concrete cylinders.

*Federally Funded, CDOT Region 4


City of Boulder Transportation
Jason Fell, P.E.
(303) 441-4007


$10.1 M Est.


Under Construction