Left: Southeast Corridor Constructors, the design-build contractor for the massive T-REX project, erected the noise wall panels. Below, left: Panels are braced prior to final setting and backfilling. Below, right: Using historic maps from the original settling of Denver, the walls remind travelers of the area's history and of the mountains looming over the plains.
Left: Southeast Corridor Constructors, the design-build contractor for the massive T-REX project, erected the noise wall panels. Below, left: Panels are braced prior to final setting and backfilling. Below, right: Using historic maps from the original settling of Denver, the walls remind travelers of the area's history and of the mountains looming over the plains.

The congested southern approach to Denver along Interstates 25 and 225 is getting a massive and much needed makeover. Dubbed T-REX (for Transportation Expansion Project) the five-year design-build project, led by the combined efforts of the Colorado Department of Transportation (CDOT), the Regional Transportation District (RTD), and the Southeast Corridor Constructors (SECC), will add an extra traffic lane in each direction through one of the city's most-congested corridors plus 19 miles of double-track light rail and reconstruction of eight major interchanges and 20 bridges for a final price tag of $1.67 billion.

In many parts of the project, the highway is below the level of the homes on either side within vertical retaining walls as high as 20 feet. In other areas, mechanically stabilized earth walls are used. To mitigate the noise created by the huge volumes of traffic on I-25, and to meet federal guidelines, CDOT/RTD decided to use concrete noise walls for at-grade sections. Through the efforts of Steve Wilensky, Carter Burgess, which did the initial project planning, T-REX decided to create a consistent visual image for all of these vertical concrete surfaces—what they called “visual mitigation.” The project's Urban Design Task Force, composed of landscape architects, engineers, and local art studio, Surface Strategy, met with citizens to develop the initial ideas. As ideas took shape, the task force went to neighborhood meetings to show the storyboards of proposed walls and gather input.

The final design, with over 8 miles of walls, incorporates historic themes for the area, including buffaloes, tipis, cottonwoods, swallows, and grasses. Surface Strategy and owner Barb McKee developed an overall scheme that allowed panels to be interchanged in different ways while still maintaining continuity in the patterns across seams. Scott System worked with Surface Strategy to create the form liners for the pre-caster to use in making the sound wall sections or MSE panels. The liners all lasted well throughout the duration of creating the panels. “When we are done with them,” says Scott System's Buck Scott, “CDOT will retain the liners and no one else will be allowed to use these patterns.”