Project Details

Primary contractor
Colorado Department of Transportation
$104 million
August 1987
Start Date
January 1994
Completion Date

Building Glenwood Canyon Corridor

Flatiron received national recognition for the construction of a series of projects in the Glenwood Canyon corridor of I-70. All of these projects were built under conditions of stringent environmental requirements, strict traffic disruption restrictions, harsh winters, and restricted workspace. The Glenwood Canyon Corridor included 12 miles of separated eastbound and westbound lanes. Many of the westbound lanes were constructed using elevated viaducts, while most of the eastbound roadway platform was constructed using precast retaining walls.

Over the course of 10 years, Flatiron was responsible for approximately half of the 20 separate projects throughout Glenwood Canyon Corridor, constructing the following most notable projects:

  1. Grizzly Creek West, with five precast concrete segmental bridges, four cast-in-place concrete box girder bridges, and extensive precast concrete retaining walls
  2. French Creek Viaduct, with two elevated precast concrete bridges—erected in balanced cantilever with an articulated overhead gantry—totaling 4,000 feet in length
  3. Hanging Lake Viaduct, with three elevated concrete bridges erected in balanced cantilever using an articulated overhead gantry.

Five precast segmental bridge erected in span-by-span method

Six cast-in-place concrete box girder bridges

Five balanced cantilever precast segmental concrete bridges

Eight miles of precast concrete retaining walls

American Concrete Institute
Award of Excellence, 1990
American Concrete Institute
Outstanding Concrete Project of the Year, 1993
Association of General Contractors
Build America Award, 1992
Precast/Prestressed Concrete Institute
Design Award, 1992