LOS ANGELES  – The 3,500-foot-long Sixth Street Viaduct linking Boyle Heights and Downtown Los Angeles is being replaced because of a chemical condition that is weakening the structure’s concrete. Since February 2016, nearly 2,000 feet of the original viaduct has been torn down, bringing the demolition phase to 50 percent completion.

In the most recent construction milestone, the two pairs of iconic steel viaduct arches that span across the Los Angeles River channel were removed. One of the arches is being preserved and will be incorporated into the 12 acres of planned landscaping below the new viaduct to serve as a focal point.

The HNTB-designed Sixth Street Viaduct Replacement Project is the largest bridge project in the history of Los Angeles and is being led by the City of Los Angeles Bureau of Engineering. When complete, the new signature bridge will serve as a unique addition to L.A.’s skyline and Los Angeles. HNTB was selected by the City of Los Angeles to deliver final design and construction support for the project. Completion is expected in 2019.

“We are excited to see the progress being made on this transformative project that will ultimately become L.A.’s newest architectural centerpiece,” said Terence Pao, PE, HNTB project manager. “In making way for the new replacement viaduct, our city continues to pay homage to the original landmark bridge that has played such an important role in the lives of Angelenos, and recognized by millions more around the country.”

Work continues on the massive project with the viaduct demolition scheduled for completion by the end of the year. In the next few months, viaduct foundation work will get underway with the installation of the first footings for the new structure, which will be followed by the construction of the main viaduct.

“Everyone working on this project is committed to delivering a world class viaduct that brings together the best in design, the highest standards in safety and a new level of   mobility and connectivity for residents and visitors,” said Gary Lee Moore, Los Angeles City Engineer.

HNTB has long been recognized as the industry’s leader in planning, design and construction of complex long-span and movable bridges, and the firm’s bridge designers are sought-after speakers at industry conferences.

As a leading infrastructure solutions firm in the U.S., HNTB traces its roots to the West back to work on Pasadena’s Arroyo Seco Bridge in 1914, the firm’s first year of operation.

In California, HNTB has been involved in some of the region’s most high-profile, complex infrastructure programs that are reshaping the region. In addition to the Sixth Street Viaduct Replacement Project, HNTB’s signature infrastructure projects include: Interstate 405 Sepulveda Pass Improvements project; Tom Bradley International Terminal Expansion for Los Angeles World Airports; Seattle’s Sound Transit University Link light-rail and tunnel project; San Francisco 49ers’ Levi’s Stadium; and “Green Build” expansion at San Diego International Airport. Currently, the firm is providing design and engineering services for the Crenshaw/LAX Transit Project on behalf of the Los Angeles County Metropolitan Transportation Authority.

About HNTB
HNTB Corporation is an employee-owned infrastructure firm serving public and private owners and contractors. With more than a century of service in the United States, HNTB understands the life cycle of infrastructure and addresses clients’ most complex technical, financial and operational challenges. Professionals nationwide deliver a full range of infrastructure-related services, including award-winning planning, design, program management and construction management. For more information, visit www.hntb.com.