Completed by the City of Los Angeles Bureau of Engineering and opened to the public in July 2022, the new $588 million Sixth Street Viaduct is the largest bridge project in the history of Los Angeles.
Project Background
The viaduct replaced the 1932 original, beloved bridge, which had been deteriorating for decades due to Alkalai Silica Reaction. This condition is caused by an aggregate in the concrete that drew in moisture and caused cracks. After repeated attempts to retrofit the old bridge the decision was made that it needed to be replaced.
In 2012, after much outreach and consultation with the community, the Bureau of Engineering (Engineering) held an international design competition to select a design for the new viaduct. Michael Maltzan Architects, a local Los Angeles firm, and HNTB, were the winners with the design, called "The Ribbon of Light".
In 2016, Engineering began demolition of the old bridge. Demolition took nine months. Upon completion, construction began on the new viaduct.
The project was funded by the Federal Highway Administration and the California Department of Transportation, and the City of Los Angeles.
Features of New Viaduct
In addition to 10 sets of LED-lit arches that can change color, the new viaduct also has:
● Sidewalks on each side of the viaduct, varying from 8’ to 14’ in width.
● 10’ wide Class IV protected bike lanes along each side of the viaduct.
● The east ramp in Boyle Heights is a 3.5 level helical structure connected by paths to both the north and south sides of the viaduct .
● The helical ramp is 790’ long, 12’ wide, and 45’ tall.
● A 510’ long west ramp from the north side of the bridge to the ground near Mateo Street.
● Five sets of stairs connecting the viaduct to the ground underneath, which will open when the new Sixth Street Viaduct PARC is completed in 2026.
Grand Opening Celebration - Sixth Street Viaduct - July 9-10, 2022
THANK YOU FOR JOINING US!!!!
All Photos Courtesy of Gary Leonard
History of the Original Sixth Street Viaduct
Constructed in 1932, the original Sixth Street Viaduct (also known as the Sixth Street Bridge), was an important engineering landmark in the City of Los Angeles. It was one of a set of fourteen historic structures crossing the Los Angeles River, and the longest of these structures.
Located in a highly urbanized area just east of downtown Los Angeles, the original bridge acted as a critical transportation link between the neighborhoods of the Arts District on the west side and Boyle Heights on the east side. The Sixth Street Viaduct was often used to represent Los Angeles’s more gritty side in countless movies, music videos and TV commercials, including riverbed car chases.
The original Sixth Street Viaduct had an overall length of 3,500 ft., and extended east-west across the Los Angeles River, multiple railroad tracks, US 101, and several local streets. It had a 46-foot wide, four-lane roadway with 11-foot eastbound and westbound inside traffic lanes and 12-foot outside lanes with no shoulders. There were sidewalks of varying widths on both sides.
Due to its large size, the original Sixth Street Viaduct was constructed using an onsite concrete mixing plant, unlike the other river bridges. Unfortunately, the aggregate used in the concrete caused a chemical reaction known as Alkali Silica Reaction, which caused deterioration of the concrete structure within 20 years of its completion.
Over the years, various costly restorative methods were tried in an ongoing effort to save the viaduct; all of them failed. Seismic vulnerability studies concluded that the viaduct had a high vulnerability to failure in the event of a major earthquake, along with geometric design and safety deficiencies. Studies showed it needed to be replaced.
About the Sixth Street Viaduct Replacement Project
The Bureau of Engineering, under the leadership of City Engineer Gary Lee Moore and in partnership with the City's Bureau of Contract Administration, led the Sixth Street Viaduct Replacement Project to replace the original, seismically-deficient structure.
The $588 million viaduct is the largest bridge project in the history of Los Angeles. It was funded by the Federal Highway Transportation Administration and the California Department of Transportation, as well as City funds.
The design of the new bridge, known as “The Ribbon of Light”, was created by HNTB and Los Angeles architect Michael Maltzan. Construction is led by contractors Skanska Stacy and Witbeck. The design was selected by the Bureau of Engineering through an international design competition.
The project created hundreds of jobs, adding to the economy of central Los Angeles and its neighbors.
Viaduct Design Fact Sheet
Design Aesthetic Advisory Committee
In 2012, former Mayor Villaraigosa appointed nine community leaders and professionals to the Design Aesthetic Advisory Committee (DAAC) to provide input during the design of the new structure.
The Design Aesthetic Advisory Committee (DAAC) provided input on:
- Bridge aesthetics for the new structure
- Associated roadways under new structure
- Colors, textures, lighting, railings
- Community/City gateway monumental elements
Committee Members
Hitoshi Abe
Chair, UCLA Dept of Architecture and Urban Design
Principal, Atelier Hitoshi Abe
Cesar Armendariz
President of Board of Directors, Boyle Heights Chamber of Commerce
Professor USC Marshall School of Business
Yuval Bar-Zemer
Arts District Resident
President and CEO, Linear City, LLC
Jonathan Jerald
Arts District Resident
Secretary, Los Angeles River Artists Business Association (LARABA)
Tony V. Harris, PE
Partner, Point C, LLC
Ozzie Lopez
Executive Director, Boyle Heights Technology Center
City of Los Angeles Community Development Department
Lewis MacAdams
President, Friends of the Los Angeles River (FoLAR)
Eric Owen Moss, FAIA
Principal, Eric Owen Moss Architects
Director, Southern California Institute of Architecture (SCI-Arc)
Doug Suisman, FAIA
Principal, Suisman Urban Design
Community Advisory Committee
The Community Advisory Committee (CAC) for the Sixth Street Viaduct Replacement Project was formed to advise the Bureau of Engineering during the process for the Environmental Impact Report and Planning.
The CAC members were a cross section of community stakeholders who served on the committee on a volunteer basis. Members of the CAC included business owners, residents, non-profits, law enforcement officials, City of Los Angeles representatives, elected official representatives and film industry representatives.
The CAC process helped to address concerns during construction and also give the public a role in the development of the design of a new bridge. The CAC process helped the City develop community ownership and community consensus on design, recreational and safety features
Viaduct Diagram
Arches Information
- There are 10 pairs of arches.
- Arches have a 9-degree outward cant and support the bridge deck with a cable network.
- Cables have a 2 3⁄4” diameter.
- The arches are 10’ wide, with a typical arch span of 300’.
- There are three different arch heights on the new viaduct:
Over the railroads: 60’ - 2 pairs Over US 101: 40’ - 1 pair Remaining arches: 30’ - 7 pairs.
"Bridging Los Angeles" Documentary
A documentary was made by the Bureau of Engineering and was screened for the public in January 2016. You can watch the film here. The film focuses on the history of the Sixth Street Viaduct, as well as the other historic bridges along the Los Angeles River.
Filming on the Sixth Street Viaduct
All filming requests should be directed to FilmLA:
FilmLA Main Phone: 213-977-8600
Website: http://www.filmla.com/getting_started.php