These beaches are among LA's favourites. But they're fake

In the early 1900s, Miami was the place to be. Miles of golden sand, the warm, turquoise ocean and temperature climate made the Florida city a hotspot for tourists.

Across the country, over on the Pacific Ocean, the beaches of Los Angeles were rocky and wild – steep cliffs dropped off to the cold, crashing waves and the Southern Pacific train chuffed along the railway tracks that ran parallel to the ocean. "City officials wanted to turn Santa Monica [one of the beach towns] into the American Riviera," explains Elsa Devienne, assistant professor of history at Northumbria University in the UK, who recently published a book about the history of Los Angeles' beaches. "Santa Monica wanted to establish itself as the resort city for the rich and famous. These beach cities had big ambitions."

The small stretches of sand that were available in Santa Monica and Venice were already heavily crowded by the new families that had descended on the city during the 1920s population boom.

"The beaches were so narrow," Devienne continues, "that you could barely walk along them at high tide." According to Devienne's research, the beaches used to be between 75ft and 100ft wide (22.7m to 30.3m) – compared to the 500ft-wide (151m) expanse they are today.

Municipal officials took matters into their own hands. They decided to build a bigger beach.

They trucked sand from the dunes that existed further south in Playa del Rey, by what is now the sprawling Los Angeles International Airport, as well as sand from the ocean floor, and a failed project to create a marina in Santa Monica. "They thought, 'Maybe we could keep doing that and extend the beaches and that would solve our crowded beach problem,'" says Devienne.

Between 1939 and 1957, 13.4 million cubic metres – or more than 5,000 Olympic swimming pools – of sediment was dumped on Santa Monica Beach.

"They played God with that landscape," says Devienne. "LA has been really, really lucky because it kind of worked. To this day, they still have these really gorgeous, wide beaches."

But, as Devienne points out, the climate is changing, and the Los Angeles coastline is eroding. The sand that stood the test of time so well is now becoming vulnerable to storm surges and coastal flooding. In fact, Southern California could lose a third to two thirds of its beaches by 2100 thanks to sea level rise.

The luck of those vast, wide beaches may be running out. And that's where sand dunes – which naturally once dotted the coastline – come in.

Nature's protection

Thanks to the handiwork of those city officials a century ago – and current beach maintenance practices – the beaches are barren and largely devoid of life.

Those long, flat sandy stretches you enjoy when you visit one of LA's beaches are that way because of the heavy tractors that come out at sunrise to groom the beach – every single morning. It's called beach grooming, and it's been happening on Santa Monica Beach for more than 70 years. It's used to remove rubbish and promote recreational activities, such as volleyball, but it also contributes to greatly reduced biodiversity; there's less prey available for shorebirds, and a decrease in species richness.

Putting a halt to this meticulously destructive grooming was the first step for Tom Ford, president of local nonprofit The Bay Foundation, an organisation which has been fortifying the beach by restoring sand dunes.

"We were looking at what we could do to further enhance the coastline, and we knew we were facing increasing sea level rise, storms and flooding," explains Ford. The foundation knew that if they could stop the beach grooming and bring back native communities of plants to the area, sand dunes would reappear, providing a natural buffer against erosion. (A similar successful project had already happened further south.)

In late 2015, the foundation cordoned off a three-acre area (12,140 sq m) and dispersed native seeds in the sand, including beach evening primrose, sea scale, and flowering sand verbena. They watched and waited, and, thanks to some heavy rains, the seeds took root, grew and flowered.

As the plants grow, they capture windblown sand beneath their branches and leaves, over time creating natural sand dune barriers that protect against coastal erosion. The project was experimental, Ford explains, and so there wasn't any quantifiable success criteria that was set. But in Ford's view, it's been a resounding success. The dunes have already reached between one and three feet tall (30 to 90cm).

"The plants have really taken off, perhaps better than we could have hoped," says Ford. "The bigger question was how was the wildlife going to respond to that habitat and that beach, while there's still such a dramatic human presence there. Fortunately, the answer came very quickly."

A surprising return

In March 2016, Ford and his team observed that something else had returned in addition to the dunes: the federally threatened western snowy plover – a species that had not been recorded in the Los Angeles region for almost 70 years. The first nest for the LA region was found in 2017 within the dunes and contained three eggs. Since then, plovers have returned to the restoration area to nest. Native plant species that had not been planted by The Bay Foundation appeared too, such as pink sand verbena. And dune beetles – which provide food for foraging birds, and which had not been observed in baseline surveys prior to restoration – also arrived.

"Whereas the groomed control areas were flattened and uniform, the restoration area had small dune hummocks, increases in berm height, and consistent sand retention across seasons and years," a five-year report released by the foundation noted.

"It really was a breakout year," says Ford. "We were all a bit gobsmacked by the plovers. They came back frighteningly quick."

The main challenge, says Ford, was not knowing whether the public would respect the cordoned-off area. "We weren't going to build a 10m-tall (33ft) fence to keep people out, and the only way to answer the question whether visitors would respect the site was to see how it played out."

Ford was "pleasantly surprised". "Everyone has responded beautifully to it. We've never had an incident of vandalism or any kind. I've seen kids playing with the driftwood that's built up. We really hoped it would be an additive experience to the beach to see it in a more natural form. To get people to imagine, 'Oh wow, beaches don't have to be like a giant sandy parking lot.'"

In January 2023, the sand dunes were finally tested by a strong storm which brought ocean swell and high tides. The weather event caused substantial erosion at several beaches in Los Angeles, but it did not impact the restoration site, where the wave run-up stopped at the dunes – as opposed to running 20 to 30m (66 to 99ft) further up the beach at the groomed control site.

Sand dunes as a resilience tool

"Sand dunes play an important role in coastal erosion because they serve as a barrier to wave run-up and overtopping," says Timu Gallien, a civil and environmental engineering associate professor at the University of California, Los Angeles. "So, when you have large wave events that coincide with high tide, those waves in many cases would be able to overwash the beach.

"But when you have a dune structure there, you provide additional elevation. That allows those waves to run up and infiltrate the dunes, as opposed to running up and over the sand and flooding the infrastructure, car parks, building structures, and the Pacific Coast Highway that sit in the backshore."

Although Santa Monica Beach may seem wide, there are "a lot of ways to flood a beach", Gallien explains, and the wide, flat beach is not immune, especially in the face of more intense rainfall and sea level rise.

Gallien was brought on to the The Bay Foundation's project earlier this year to begin officially observing the changes in the ecosystem in the new phase of the project.

"Anecdotally we've seen that stopping the beach grooming of that area is allowing nature to take her course, and with some limited management we've started to see development of some small sand dunes and depressions on the beach, and plants and animals already coming back. So the project has evolved really nicely so far."

Sand dunes are nature's way of protecting its coast – Timu Gallien

Although it's too early for Gallien to talk about results on the Santa Monica project, a similar restoration effort she oversaw at Cardiff State Beach in San Diego has become the poster project for living shorelines – the term for coastal edges made of natural materials that protect coastal communities and provide a wildlife habitat. The Cardiff project is a hybrid structure – a dune on top but underneath a large trench. "We had a big wave event in 2003," Gallien remembers, "and the structure performed very well. It did its job in terms of coastal protection, and I think that's looked to as a potential solution statewide."

"Sand dunes are nature's way of protecting its coast," says Gallien. "But we've often paved over those or built upon them. I think these living shoreline projects are fantastic because, in effect, you're engineering with nature, as opposed to against her. And of course they're very visually appealing. I think it's the path forward for many, many coastal municipalities."

A report by a group of California scientists who have been studying the dune restoration project since its inception found substantial differences between the beach pre- and post-restoration. Dunes had visibly formed along the fence perimeter, and new plants there were buried by sand blown there by wind continued to grow above the newly deposited sand. Approximately 2,760 metric tonnes of sand had accumulated since December 2016.

The project has been such a success that the foundation has cordoned off a further five acres (20,200 sq m) and sown more native seed. They're also looking at expanding the project by another 40 acres (162,000 sq m). Other beach officials further down south, who have been eyeing Ford's success, are now chomping at the bit for their own coastal restoration projects. "People are going to love it," he says. "It's going to be gorgeous. And we're very excited to have a second bite at it."

-BBC