City Staff Recommends Cable-Stay Replacement for 6th Street Bridge
This model of the proposed cable-stay design for 6th street was constructed by Caltrans.
DOWNTOWN LOS ANGELES — A replacement design for the ailing 6th Street Viaduct should have "wow factor," City Engineer Gary Moore told a packed Boyle Heights room Thursday evening. The 1933 structure suffers from a condition called Alkali Silica Reaction (ASR). Described as "cancer," ASR combines with moisture to crumble concrete from the inside.
For the past two years, studies and community meetings have been done to determine whether the existing bridge can be saved, and what should replace it if a new span must be built. When the project's draft Environmental Impact Report comes out in upcoming weeks, it will include a recommendation by city staff that the bridge be replaced with structure featuring a modern cable-stay design.
The community meeting, held at the Boyle Heights Technology Center just across the Los Angeles River on 4th street, was at times heated. One Boyle Heights woman was particularly forceful in her displeasure, repeatedly interrupting the presentation to accuse the project team of pushing its own predetermined agenda and ignoring the community.
The project team's choice of a cable-stay design to replace the historic bridge was the night's main point of contention. Several vocal members of the audience pointed out that the project's Community Advisory Committee had cast the most votes for a design featuring metal arches similar to the existing structure.
Moore defended the team's choice. "We had to make a decision. I'm very excited about the decision," Moore said, calling the project the "new signature of Boyle Heights."
Engineer Steve Thoman explained that a recreation of the existing bridge style would face significant challenges. The 1933 viaduct crosses railroad tracks on both sides of the river. Once the existing bridge columns were removed, the railroad would have to give its permission for new supports to be installed. Thoman said that the team has had meetings with the Union Pacific, and the railroad has no interest in seeing that happen.
Without the columns across the tracks, Thoman said that a recreation would look fake and out of proportion. "It's like a baseball player," he told the crowd. "If he wears a football helmet he can still go up to bat, but it looks funny."
The new design faces significant constraints. Below run the river and railroad tracks, and above cross high voltage power lines that are part of DWP's transmission network.
Along with a new design, the rebuilt bridge would widen the roadway while not adding lanes, creating new space for bicycles and pedestrians. It would also turn 6th street's existing kink into a gentle curve, eliminating the span's prime spot for accidents. That change would require the acquisition of properties along the new right-of-way, and several attendees at the meeting were property owners whose parcels would be purchased. The project team has done interviews with forty business owners along the new alignment.
The project team hopes to have a Record of Decision on the project recorded later this year. That would kick off two years of right-of-way acquisition and engineering work, followed by four years of construction. 6th street would be out of service from 2012 to 2016.