Demolition of Sixth Street Viaduct is initial step to replace L.A.'s historic bridge with new HNTB design

One of America’s most famous and iconic bridges, the Sixth Street Viaduct needs to be replaced because of a chemical condition that is weakening the structure’s concrete.

In the most recent construction milestone, the initial 220-foot section of the viaduct above the 101 Freeway was successfully demolished in early February 2016.

Advance planning by the City of Los Angeles Bureau of Engineering and Caltrans ensured drivers were aware of closures and alternate routes, minimizing the impact of the 40-hour closure of two miles of the 101 Freeway. Removing the entire 3,500-foot viaduct is expected to take approximately nine months. Anticipated completion of construction is 2019. The 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 LA’s skyline and the Los Angeles River as it improves mobility, enhances safety and connects communities.

“While it’s sad to say good-bye to such a historic bridge, we are excited that this transformative project is underway and upon completion, will offer Angelenos a place to gather, have fun and connect with their community,” said Vic Martinez, PE, HNTB vice president and project manager.

Work continues on the massive project, including viaduct demolition, and the start of bridge foundation work in the coming months. An estimated 48,000 cubic yards of concrete, 1,245 tons of structural steel and 4,200 tons of rebar will be hauled away as construction begins on the replacement viaduct.

When completed in 2019, the new Sixth Street Viaduct will be a world-class, iconic piece of architecture serving residents of the City of Los Angeles, create its own legacy and draw aspiring artists and others to its ‘ribbon of arches.’

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.

At the recent Transportation Research Board’s 95th Annual Meeting, HNTB’s Jim Grant, PE, was a workshop presenter for Measuring Sustainability, Using INVEST and Envision to Assess Transportation Projects and Plans. His case study presentation on the Sixth Street Viaduct - Improving the Community Qualify of Life with ‘The Ribbon of Arches’ - briefed participants on how transportation agencies can use sustainability rating systems for strategic planning, performance metrics, public participation, and asset management.

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 Southern 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.

# # #

For more information, contact:

Agnes Huff, Agnes Huff Communications
ahuff@ahuffgroup.com; (310) 641-2525