Caltrans completed this innovative and award-winning bridge replacement project in less than eight months
By Julia Edinger
The landscape of coastal California is prone to landslides after a rainstorm, which makes building resilient infrastructure on this landscape quite a challenge. Caltrans accepted this challenge – embraced it. The award-winning Pfeiffer Canyon Bridge Replacement project exhibits the success of determined reconstruction efforts.
The structural issues with Pfeiffer Canyon Bridge were first brought to the surface after being noticed by a homeless man. He informed the local roadway maintenance engineer, and the bridge closed in less than 40 hours. While the risks seemed to be mitigated, the deficiencies were hidden below the surface, as is often the case with infrastructure.
Inevitably, in the months of late winter and early spring in 2017, a storm hit that would shift this bridge replacement into high speed. The storm exposed the extent of the bridge’s deficits: the soil was moving underneath the column – so much so, that it was impacting the superstructure of the bridge.
The bridge plays a critical role for people living and working in the area. The Pfeiffer Canyon Bridge connects Highway 1, allowing people to travel and commute between parts of Monterey County. When those in the northern parts of Monterey County were isolated from those in southern Monterey County in Big Sur, it was clear that the damage demanded replacement. It created such a strain on the community that Caltrans had to act fast to restore travel on Highway 1.
The brunt of the funding came from State Emergency Budget funding, as the deficits truly had created a state of emergency for the region. This state also allowed the state to apply for federal funds, which reimburse 75 percent. Caltrans would end up completing the project over two million dollars under budget, at $21.7 million.
“Once the superstructure started deflecting,” said David Galarza, Structures Representative, D05 North, for Caltrans, “I think initially we thought we could just retrofit the damaged column by supplementing some additional columns and constructing an outrigger type of a bent scenario. But once that second storm hit and the superstructure was impacted, we pretty much knew the bridge was done for. And then we kicked it into high gear designing a replacement.”
The structural design was completed within three weeks, featuring steel spanning over where the landslide from the storm was. The steel was available, and the site did not require too much additional preparation before assembling steel girders and launching them over the canyon.
Caltrans was very engaged with the project throughout the process. Before the removal of the existing bridge was even complete, the department was seeking bids for steel suppliers. As the supply and finance aspects of the project were being determined, the old bridge was being removed, and new abutments were being constructed.
“The old bridge was a three-span bridge with two pile columns,” said Galarza. “Obviously one of them was compromised, so we wanted to work around that and have a simple stand. So we just had two abutments in the new design. We also had to construct temporary support to launch the girders once they were assembled across the canyon. So there was a bunch of fieldwork that was happening concurrent with the girders being fabricated.”
There were so many wheels spinning at one time in this project’s implementation that it was completed quickly. Days after the abutments were completed, the assembly begun. First, the department had to align and assemble the girders. Then, they had to launch and lower the abutments to their seats about 18 feet down, a process which took about four days. After that, came lowering the girders, which took about two weeks, and was a challenge in the process. But after those parts were secured, conventional work methods allowed for quick completion of the forming and casting the reinforced concrete deck. The final touches – adjacent approach lodge, roadway section, barrier rail, profile grinding – were completed smoothly and efficiently, allowing the bridge to be reopened to traffic on October 13th, 2017.
Caltrans could see that the community was enduring the difficulty of the situation while the road was closed; the community acknowledged the gravity of the project. Coastal projects can always be controversial due to the traffic, especially during the summer season when tourism already brings in a higher level of traffic. Caltrans worked with the community, involving them and educating them about the project, which made them much more respectful in regards to the inconveniences associated with the project.
We had some locals who would visit the job and schedule times, and we would give them impromptu tours to let them know what we were doing, and they would document that and they would put it up on social media,” said Galarza. “That way the community was almost being taken along through the life of the job so they could see what we were working on.”
While coastal projects on Highway 1 tend to be controversial for the impediments to traffic flow, there was strong support of the community for this project. Team members acknowledged the rarity of this, especially because working season for construction projects like this occurs simultaneously with tourism season.
“You’re restricting traffic in normal situations to one lane,” Galarza explained. “The tourists don’t mind, most of them, waiting a few minutes, but the locals can get upset from time to time.”
For those commuting regularly between work and home, losing the only connection between northern and southern Monterey County was not a minor adjustment. The project leaders worked tirelessly to ensure that it was an inconvenience rather than a complete disarray. Educating and involving community members was a vital part in easing the public reaction, and ultimately, gaining community support.
By involving the local residents of the community, as well as local business leaders, Caltrans managed to maintain the community’s support despite the project’s challenges. Ultimately, that was a main factor that led to the project’s success.
The project received an award for “Best Use of Technology and Innovation” in 2018 from the 11th annual America’s Transportation Awards competition. The success of the $24 million bridge project was undeniable. Rebuilding a bridge of this scale is usually a multi-year project, but Caltrans was able to finish the bridge replacement in less than eight months.
Galarza described the opportunity to work on the project as a, “Once-in-a-career type of job.” He stated, “Myself and my staff all have 20-30 years worth of experience working in this area, and these jobs usually only come around once in a lifetime, and we were certainly proud to be a part of it.”
Julia Edinger is the Assistant Editor at American Infrastructure Magazine. She can be reached at email@example.com.