Could part of Highway 1 be moved inland? 

The plan, which was submitted to the California Coastal Commission by Caltrans in November, offers long-term alternatives to protect the threatened highway, including various combinations of moving it in by around 200 feet, raising the road with a bridge structure and more nature-based defenses. 

If the highway was to be moved inland, it would overlap directly with a planned Granada Community Services District park and recreation facility on the Burnham Strip, as well as underground wastewater storage owned by the Sewer Authority Mid-Coastside. 

GCSD has been planning for a park on the land, which it owns, for years, said Barbara Dye, president of its Board of Directors. Because the proposal to move the road is so preliminary and would require years more analysis and community outreach, plans for the park will be moving forward barring complications. 

“Before there is any serious look at moving Highway 1, there would have to be so much more analysis,” she said. “We are finally getting close to the final submittal to get our park approved by the county.” 

Caltrans plans also ignore local efforts to address erosion around Surfers Beach, James Pruett, San Mateo County Harbor District general manager, said. He stressed that erosion has been occurring at such a high rate in the area because breakwaters built in the 1960s trap sediment inside the harbor and change the wave pattern. 

The Harbor District recently attempted to mitigate the issue via a dredging program, moving sand from inside the harbor to Surfers Beach. The Harbor District is also planning another project along the Princeton shoreline to deal with erosion impacts. 

“Caltrans doesn’t take anything into consideration. They don’t take anything the Harbor District is doing for long-term planning,” Pruett said. “I think the document is not worth the paper it’s written on.” 

Solutions like the one piloted at Surfers Beach, as well as other potential options like establishing offshore structures to regulate wave patterns, would all be a better place to start than relocating the highway in its entirety, Pruett said. 

“If we address the cause of the erosion, the highway doesn’t have to do anything,” he said. “It can stay where it’s at.” 

The transit agency is continuing to evaluate all alternatives, which were submitted as part of a permitting process for other work going on along Highway 1. 

“Caltrans will be working in conjunction with the Coastal Commission, the local cities, the county of San Mateo, residents and other stakeholders as we consider our next steps for coastal adaptation projects,” Caltrans Public Information Officer Jeneane Crawford said. 

Bringing the highway inland and elevating it “would address all three major threats: erosion, [sea-level rise] and flooding due to extreme storm events,” the November Caltrans report said. Elevating the highway but leaving it in its current location would not provide the same level of protection, the report said. 

Other less-invasive solutions, like the sand relocation Pruett highlighted, have a lower impact but higher cost and construction constraints and require semi-regular maintenance, the report said. Building a bridge only slightly inland of the existing highway could also protect the road from sea-level rise for the foreseeable future, and a hybrid approach combining these strategies could be another possibility. 

“In the near term, offshore cobble berms and onshore sand nourishment could help slow bluff erosion, while the major realignment of [Highway 1] via a bridge would offer a more permanent and resilient adaptation strategy, especially when combined with the nature-based solutions,” the report said. 

Dye emphasized that any project is still in its infancy. 

“This is very early in the process,” she said. “When the time comes they actually have to address that, there will have to be a lot more work down the road, and lots more community outreach.”