Trancas Bridge in ‘Critical Shape’

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Damage photographed in 2016 on the Trancas bridge.

Built in 1927, the 89-year old bridge on Pacific Coast Highway that crosses Trancas Creek is on its last legs.

Matt Holm, a Caltrans structural engineer, performed a visual inspection under the bridge before a scoping meeting that took place last Wednesday, Jan. 27 at the Malibu West Beach Club.

“I could literally break concrete off with my bare hands when I looked at the bridge today,” Holm explained. “The rebar is rusted and exposed, and one of the columns [holding up the bridge] has split. The other three columns are doing all the work. It’s time to get this thing replaced.”

Senior Environmental Planner Karl Price said the nearly 90-year-old bridge had only been designed for a 50-year lifespan, meaning it probably should have been replaced back in 1977.

He said the bridge was widened in 1938, and experienced “scour and erosion problems” from 1967 to 1998 that were repaired at various times with riprap, regrading and stabilization of the dikes.

“The cheap repairs have been done already,” Holm said. “There are no more cheap fixes.”

“It’s an old bridge with a history of scour problems and several non-standard features,” Shahriar Yadegari, transportation engineer, said. “We want to replace this bridge with a safer bridge that meets current design standards. As of now, the railings don’t meet safety standards and the design does not meet earthquake standards … A new bridge will also be structurally sound, have room for a bike path, a 75-year lifespan, better aesthetics and less impact on creek flow.”

Caltrans presented three options at the public scoping meeting last week, with the first option being “do nothing.” The second and third options that Caltrans presented consisted of two different bridge replacement designs.

The “short” bridge option would be six feet wider and 20 feet longer than the existing bridge. $5.7 million has already been set aside to build it. 

The “long” bridge option would be six feet wider but 140 feet longer than the existing bridge. It would cost a few million dollars more to build ($8.6), but would accommodate a wider flow and perhaps be more environmentally friendly for a proposed lagoon and steelhead trout restoration project on the old “Riders and Ropers” lot adjacent.

Although the California Coastal Commission suggested the more expensive bridge design, Caltrans was unsure if they could get the extra money to pay for it. 

The Resource Conservation District of the Santa Monica Mountains (RCD – SMM) is the lead agency on the lagoon project. Senior Conservation Biologist Rosie Dagit said they may be able to apply for a grant to make up the difference. 

The scoping meeting was attended by about 30 people, with a number of questions and public comments. The biggest concern was whether PCH would be shut down for any or all of the construction, which is estimated to take almost 14 months, from June 2018 to August 2019 — two consecutive summers.

Caltrans explained that they “had yet to develop a traffic plan for the project,” but most likely PCH would be down to two lanes (one lane going each way) instead of four lanes for extended periods of time. They would demolish and then rebuild half of the bridge at a time, working on a trestle and with a crane. They explained that “PCH will never shut down altogether.”

“We’re trying to shorten the time and not have it continue over two summers,” Yadegari said. “We’re trying to have as little impact as possible on the community, and we’ll try to make sure everybody is warned [about lane closures].”

Elizabeth Shavelson and Bob Brager, both with the City of Malibu, asked Caltrans to provide enough space on the new bridge for cyclists, pedestrians and cars.

“We just completed a Class II bike lane along Zuma [Beach] that we’d like to continue over the bridge,” Brager said. “And having an under-passage for pedestrians is critical.”

Although there was a fair amount of griping over the inconvenience of having two lanes of PCH shut down at a time, especially with summer traffic, some pointed out that if the bridge collapsed on its own — a definite possibility — PCH would be entirely closed down at Trancas.

Resident Barbara Cameron recalled that when the January 1995 floods damaged the Malibu Lagoon Bridge, PCH was closed for a time. If Caltrans had not had plans for the bridge’s replacement in the works already, she said PCH near Cross Creek would’ve been closed much longer than it was.

 

Comments on this project can be submitted to Caltrans up to Feb. 27. Contact Karl Price at 213.897.1839 with questions or comments.