L.A.’s New Sixth Street Viaduct Project Named Year’s Most Outstanding Engineering Triumph

On Tuesday, the new Sixth Street Viaduct Project in Los Angeles won the 2023 “Grand Conceptor” Award signifying the year’s most outstanding engineering achievement.

The project was honored at the 57th Annual Engineering Excellence Awards Gala (EEA)—a national juried competition awards ceremony sponsored by the American Council of Engineering Companies (ACEC).

Hosted by noted comedian Ross Shafer, Tuesday night’s EEA Gala honored 179 outstanding engineering achievements from the U.S. and worldwide.

Designed by HNTB of Los Angeles, the Sixth Street Viaduct is a 3,500-foot tied arch bridge locally called the “Ribbon of Light.” The structure re-establishes a critical thoroughfare between L.A.’s historic Boyle Heights on the east side with the Downtown Arts District on the west.

Paying homage to the original double-arched 1932-era predecessor, which closed for demolition in 2016, the new viaduct features ten pairs of sculptural 30-and 60-foot concrete arches. Each arch is supported by an innovative seismic isolation system designed to withstand a 1,000-year seismic event. It also is the largest bridge project in the history of Los Angeles.

The project will also include a new 12-acre public park running below the bridge, accessible by multiple stairways and a monumental helical bike ramp, is currently under construction

The project joins a prestigious list of recent Grand Conceptor Award winners, including the Moynihan Train Hall(New York, NY, 2022), Copperhill Watershed Restoration (Ducktown, Tennessee, 2020); and the SR 520 Floating Bridge Replacement (Seattle, 2017).