ConDig (14-Feb-24)  Civil contractor and construction materials producer Granite Construction has driven off with a $112 million contract to revamp a highway in Denali National Park, Alaska.

Under the deal with the Federal Highway Administration (FHWA), Granite has been appointed as construction manager and general contractor on the Polychrome Area Improvements project at the Pretty Rocks Landslide, which intersects Denali Park Road near its midpoint.

The project includes construction of a 475-foot-long single-span steel truss bridge to span the active landslide. Supporting the bridge and improving ground conditions is a combination of earthwork, micro piles, rock anchors, soil nails, precast/post tensioned concrete abutments, and thermosyphons. 

Thermosyphons are part of a passive heat exchange system designed to prevent permafrost from thawing and creating instability, according to Granite. 

Construction of the Polychrome Area Improvements project began in 2023 with mobilization, development of a worker camp, pioneering access across a landslide, blasting, and mass earthwork. 

Work planned for the 2024 season includes completion of mass earthwork, construction of the bridge abutments, installation of a temporary launching system, and partial erection of the structural steel bridge. 

Bridge erection will continue through 2025, along with launching of the structure to span the landslide. 

For the 2026 season, construction includes setting precast bridge approaches, building a retaining wall, installing thermosyphon condensers, coating the bridge deck, and demobilization.