U.S. 36 Design-Build

Ames’ two-phased design-build reconstruction of U.S. 36 between Boulder and Denver, Colorado, produced multimodal options for commuters, expanded capacity, and eased traffic congestion.

Phase 1 reconstructed 10 miles of U.S. 36, adding express lanes for bus rapid transit (BRT), high occupancy vehicles (HOV), and tolled single occupancy vehicles (SOV). Crews widened the highway, reconstructed other corridor elements, and installed a bikeway along the highway that ties into existing trail systems.

Phase 2, a Public-Private Partnership (P3), added express lanes and widened the highway along an additional 5.5-mile segment of U.S. 36. This phase included construction of four new bridge structures, the widening of two existing bridge structures, and repair of 15 bridges along the HOV lane.

One of the project’s unique features was the use of a diverging diamond interchange (DDI). At this style of interchange, traffic crosses to the opposite side of the road so that vehicles have unimpeded movement onto the freeway. Despite using fewer lanes, this innovative interchange can handle more traffic, reduce traffic signal delays, increase left-turn capacity, and eliminate wrong-way entry to ramps. This was just the third DDI to be built in Colorado.

Ames maintained a crushing yard on-site to reduce hauling and mobilization of materials, and all of the project’s asphalt paving was recycled and reused in the project.

Learn more: Colorado Department of Transportation