Environment |

Can San Clemente recreate Trestles and T-Street surf breaks in attempt to save sand?

Can the eroded beaches at the north and south ends of sand-starved San Clemente be reconstructed to mimic the world-class waves at Lower Trestles or the popular T-Street surf break in an attempt to keep sand in place?

Would jetties – like built in West Newport to save its beaches from severe erosion in the ’60s – help to save Capistrano Shores where waves batter beachfront homes when big swells hits?

The city’s coastal planners held a town hall on Wednesday, Sept. 27, to brainstorm ideas with the community for how to bring back – and keep – sand on San Clemente’s shoreline, exploring innovative ways to beef up beaches that have diminished rapidly in recent years.

The proposals follow a report earlier this year on the city’s most critical erosion spots – some of the narrowest stretches have nearly no beach at all during mid-to-high tides.

A massive, $15-million sand replenishment program 20 years in the making is expected to kick off later this year and then be repeated periodically by the Army Corps of Engineers over the next five decades. It will initially add 250,000 cubic yards of sand between T-Street, around the pier, and north to Linda Lane. The question is how to retain the sand and capitalize on that project and help other eroding beaches as well.

Living shorelines – dunes with native vegetation to help keep sand in place – are proposed for those areas to help keep that sand in place.

San Clemente is a unique project with an opportunity to make it a better coastal place that provides the amenities of a wider beach to play on and enjoy and maybe also create new habitat for wildlife and more recreational opportunities such as surfing, said principal coastal scientist Chris Webb from Moffatt & Nichol, the consultants hired to lead the city’s efforts.

More out-of-the-box, innovative ideas for man-made reefs are proposed on the north and south ends of the city, where beaches are deemed either “critical” or “threatened.”

The Capistrano Shores area on the north end of San Clemente had two options on display during the town hall, one with perpendicular groin jetties like Newport Beach.

Another proposal for that area would be perpendicular offshore reefs that would slow down wave action, three rock piles built to above sea level with gaps so water could flow between – potentially creating surf breaks.

North Beach, where a concession and bathroom building is at risk of pounding waves, could be an ideal place to create a triangle-shape reef to mimic Lower Trestles.

Researchers took a 3-dimensional underwater photo of the Lower Trestles surf break and set it out onto a map of North Beach for context, Webb said.

Cobblestone, boulders or even cut, flat rocks could be placed down under sand supply added at the shoreline, with rocks extending into the ocean in a v-shape, he said.

“It’s basically making Trestles as best we can and have it stay there,” Webb said. “We can try to make it as surf friendly as possible with the angle that is laid out and the distance from shore.”

It would need a lot research before it could be attempted, Webb said. “It would probably have to be replicated in a physical laboratory, where it’s built in a reduced scale as a model and a wave machine pushes waves on it to see how well waves dissipate before they get to the shore.”

And it would be no easy task, with challenges such as timing rock placement on days with small swell so a barge could get into the surf zone.

Mariposa Beach, also identified as a “critical” area, could benefit from a similar approach. But that, too, would come with challenges due to sensitive sea grass.

That same v-shape artificial reef could be built further south at Cyprus Shores, another “critical” beach where waves have undermined the toe of the bluffs and triggered a landslide that shut down rail service through that area multiple times in recent years. Adding heavy rocks and loading the beach up with sand could help stabilize the hillside.

Suzie Whitelaw, a geologist with the community activist group Save Our Beaches San Clemente, had several suggestions, including adding alternatives for perpendicular reefs, rather than just the v-shaped ones, to areas of North Beach, Mariposa and Cyprus Shores.

She worries the bigger cobblestone rocks would create hazards for kids in the surf line, she said.

Whitelaw also suggested planners instead look to T-Street’s reef as a model, since it seems to be working for that sandy, stable beach.

“I have confidence in you to engineer something that would last and replicate T-Street, I think the whole community could get behind more T-Streets,” she said.

She preferred the offshore reef models because they can be built up in future years.

“I see them not only as a sand-retention device, but a resilience structure. They are going to break that wave energy – that protects our beach and infrastructure,” she said. “And if, and when, sea level does rise, they are smaller structures than these big things and you just add more rocks. They could go upward.”

She also suggested meeting with surfers to map out the breaks to know what currently exists along the city’s coastline.

Susan Ambrose, a member of the city’s Coastal Advisory Committee, reiterated the need for a regional approach and for the city to work alongside other beach towns and the county for future “opportunistic” projects, because the amount of sand coming from the Army Corp won’t be enough and won’t last, she said.

Speaker Don Brown wondered about the likelihood the California Coastal Commission would approve any of the ideas discussed.

Leslea Meyerhoff, the city’s new coastal administrator, said the proposals are based on the commission’s guide for cities planning for climate change resilience, and the city has been communicating with its staff.

Surfrider Foundation environmental attorney Elizabeth Taylor said it makes sense to focus on realistic ideas that are more likely to get approved, rather than wasting time and money on ideas that likely won’t get the green light. She argued for a more ecological approach, rather than any hard structures.

“I worry about some of these proposals and some of the potential negative impacts they can have on the stretches that are currently stable. There are unforeseen consequences, especially with big, massive, fixed structures being proposed tonight,” she said. “Make sure we are not doing any harm.”

John Dow, also a member of the Coastal Advisory Committee, applauded the ideas and said the city needs to take proactive, speedy action.

“We have to consider the alternative,” he said of walls of boulders that have been built in response to emergency situations. “We can either have rock structures laterally along the beach and no beach, or we can have rock structures thoughtfully placed that retain sand, provide recreation and provide the buffer we need.”

Following draft studies next year, city officials hope to have a final proposal to present to the Coastal Commission by Dec. 31, 2025.