‘No Perfect Solution:’ Malibu Fights Coastal Erosion

A photo illustration of Ralphs Beach. Photo illustration by Ali Levens. Photos by Lucian Himes

Interactives by Zack Born

Westward Beach is caught between a rock and a hard place — or, the ocean and the stone cliffs rising behind it.

This is the dance of coastal erosion, and Westward Beach is just one beach of many facing land-damage issues.

Coastal erosion is when sea levels rise and strong wave action or coastal flooding clears away rocks and soil — causing the coast to erode, according to U.S. Climate Resilience Toolkit.

As the global temperature increases due to climate change, ice caps in the Earth’s polar regions melt, causing ocean levels to rise, according to Britannica. Additionally, a warmer Earth means stronger storms, compounding the existing problem.

In the United States alone, coastal erosion has caused approximately $500 million per year in property loss on coasts across the country, according to the Office of Coastal Management. In addition, the federal government spends approximately $150 million every year on coastal erosion prevention measures.

“It’s tough,” said Karen Lynn Martin, distinguished professor emeritus of Biology. “It’s the kind of question that every community is facing right now — how do you keep the things that you love, as long as possible and as sustainably as possible?”

As the rate of coastal erosion increases, scientists and policymakers are discussing how to save the beach, Martin said. One option is supplementing the beach with rocks, and the other is expanding Westward Beach Road, which will take away part of the usual beach, but may preserve the rest.

Martin said whatever solution people decide, there needs to be compromise; there is “no perfect solution” when it comes to maintaining both public access and the beach visitors love.

How Coastal Erosion Affects Malibu

In Malibu, beach erosion is prevalent and a concerning problem for homeowners and business owners along the coast, Mayor Paul Grisanti said. Grisanti is also a member of the board of Smart Coast California, an organization advocating for collaborative stewardship of the coast.

Rising sea levels wear away the coast, and factors such as the lack of dams, lack of flood basins and runoff from storms cause beach erosion, Grisanti said.

“That’s one of the many reasons that Broad Beach is not as broad as it was when I first came to Malibu 44 years ago,” Grisanti said.

Grisanti said the most obvious points of coastal erosion in Malibu are by the Getty Villa, the northern end of Malibu and by Palisades Beach Road.

Martin said there are two things happening along the coast: the sea level is rising, and storms are escalating in both strength and frequency. These factors increase erosion and speed up the loss of beach habitat, especially on sandy beaches, where sediment is loose.

The change in beach size happens seasonally, Martin said, but these events make the decline much more dramatic.

While rocky areas may not wash away like a sandy beach, rising sea levels can cover them with water, Martin said.

“Those animals and plants that need to be in the air or those that are adapted to be in both water and air may find themselves inundated more than they would prefer to be for their survival,” Martin said.

Coastal Erosion in Another Time

When Grisanti was in college, the scientists studying coastal erosion stated the beach was eroding at approximately one foot a year in Santa Barbara. Grisanti said the beaches in Malibu are lucky to have different geology — geology that causes them to erode little by little.

“About three years ago, it [coastal erosion] was supposed to turn sharply upward,” Grisanti said. “In reality what’s happened is it’s stayed on a little bit, little bit, little bit range, which is — it’s a long term thing.”

For example, geologist Polly Bickel found in a 1999 study that 14,000 years ago, Malibu Bluffs Park — across from Pepperdine — was underwater.

“I don’t know because I wasn’t here at that time,” Grisanti said. “I know it because geologists did some work there and they found evidence that it was underwater, and so the sea level rise goes up and goes down.”

Grisanti said there are parts of the coast where land is rising faster than the sea level, preventing coastal erosion rise, like in Northern California, showing that beaches are not a static system.

A variety of factors contribute to land rise, according to NASA’s Earth Observatory. For example, in the Livermore Valley, it is likely that an underground aquifer refilling is causing uplift. In Northern California, the tectonic plate subduction at the Mendocino Triple Junction provides more coastal uplift than what occurs in central and southern California — several millimeters per year.

Why Save the Coast?

Martin said there are a multitude of coastal habitats: sandy beaches like Ralphs Beach; gravel beaches like those in Washington or Northern California; and cobble beaches, made of rocks smaller than boulders, which often lie below sandy beaches.

Muddier areas, such as estuaries like Malibu Lagoon, are habitats necessary for invertebrates and birds, Martin said.

Some scientists have considered the rocky tide pools to be one of the most endangered habitats because of its specific and small area, Martin said. Many of the animals and plants that make tide pools their home rely on the changes that come with a low tide.

“It’s going to change who can live in those spots,” Martin said. “They’re gonna have to move up the shore, or there may not be pools further up the shore that they would be able to move to.”

Even in sandy beaches, the animals such as the sand crab will continue to get moved up with the tide, Martin said. Animals such as the grunion, who come to the beach to lay their eggs, will lose that area for reproduction.

“At some point, the beach band will completely disappear and so even those that can move won’t have any place to go,” Martin said.

Many of the animals — shorebirds, sea turtles and mussels — that use the beach for reproductive purposes are endangered, Martin said.

Coastal erosion isn’t the only problem affecting marine life. Eggs rely on a certain temperature range to develop, and if it gets too hot due to global warming, it can prove fatal.

“We’ve measured temperatures in the sand that are already too hot for the eggs to survive,” Martin said. “That doesn’t happen all the time. But you know if it happens at the wrong time, or at a time when there’s a lot of eggs out there, it could be really, really tragic.”

For sea turtles, temperatures determine the sex of the egg, Martin said. As temperatures rise, the difference between females and males increases, with fewer males.

Additionally, mating seasons for marine and shore animals are not only related to time of year, but the tides themselves, Martin said.

“To be able to take advantage of that earlier season, it would be a very big change, not just a little change of a day or two, [it] would be like weeks and months and different times of day, and it would be a very difficult change,” Martin said.

For animals such as the sea turtle and grunion, the beach is the only place they can reproduce, Martin said.

“It’s also a really important habitat, and the animals and plants that use it don’t have any other place to go,” Martin said.

The beach is important to humans too, Martin said. During the COVID-19 pandemic, when most indoor gathering areas were closed, people sought refuge at the beach.

“They were one of the most solid restoring places people could go during a very difficult time to just sort of enjoy nature and be in a peaceful place,” Martin said. “It’s very spiritual as well as a very soothing kind of environment that is inspirational to a lot of people and just great for your mental health.”

‘Hard Solutions’

Grisanti said Smart Coast California advocated for every county to file for a coastal plan.

Some solutions, such as sea walls, are known as “hard solutions” because they battle nature, Martin said.

The California Coastal Commission has certain initiatives they want residents to embrace in the coastal act — a plan to protect environmentally sensitive areas, maintain public beach access, limit urban sprawl and consider environmental justice or the equitable distribution of resources, according to the commission’s overview of the Coastal Act.

Environmentally sensitive areas include intertidal waters, wetlands, estuaries and habitats with endangered plants or animals, according to the Coastal Act. The commission also seeks to mitigate the risks to life or property in high geologic-risk areas.

“The Coastal Act defines an ‘Environmentally Sensitive Area’ as: Any area in which plant or animal life or their habitats are either rare or especially valuable because of their special nature or role in an ecosystem and which could be easily disturbed or degraded by human activities and developments,” wrote the Commission in their outline of the Coastal Act.

The commission will review coastal development to make sure it is not harming coastal resources — for the safety of both the environment and the people moving in, according to the Coastal Act.

“[The plan will] Require that new development neither create nor contribute significantly to erosion, geologic instability or destruction of the site or surrounding area, or require the construction of protective devices that would substantially alter natural landforms along bluffs and cliffs,” wrote the Commission.

Smart Coast California helps residents and business owners make a plan while still following all of the guidelines they need to.

“What we’ve done is try to promote communication about what Coastal wants, how valid their science is and get people to think about whether or not that’s what we want to do,” Grisanti said.

Coastal retreat — the process of moving homes or buildings a few feet up the coast to account for rising sea levels — is another solution, Grisanti said.

“That is actually a solution that makes sense,” Grisanti said. “They [CCC] also are trying to design the roads for that.”

Grisanti said while coastal retreat would be easy for homeowners on the northern coast of California, where they can just move up a few feet, it would not be likely for buildings such as ports or homes that do not have room to move.

“They’ve got some real problems because the port of L.A. and the other ports are all designed for about the sea level we have now,” Grisanti said. “There’s really nowhere to move the port.”

Martin said sand replenishment, or beach nourishment, is a temporary solution because it needs to be done within a decade at most.

“One of the other problems we have here in Malibu is the problem of where do you get the sand, where’s it coming from?” Martin said. “Because it’s just not that easy to get. It’s not that easy to bring the shore here.”

Most of the beaches in Southern California have lost their dunes — large hills of sand that naturally replenish the beach as it washes away — Martin said.

Another solution, Martin said, is to view the beach as a geological feature that is allowed to retreat up the coast. In state parks, such as Leo Carrillo, there are only campgrounds, and some stretches of the Pacific Coast Highway behind them. The beaches in these areas are allowed to move inland.

Houses stand behind Ralphs Beach and what is inland in October. Martin said beaches with houses behind them cannot move inward — dooming them at the cost of protecting the homes.

Beaches with houses right behind them are not as lucky, Martin said.

“What’s going to happen is — and what’s already happening is — those beaches are going to be lost, they’re going to be gone,” Martin said. “There’s no place for them to go and they’ll get inundated.”

Sea walls, Martin said, protect what is behind them, at the cost of what is in front.

“You can see these very old civilizations who have put up sea walls to protect their structures, and there’s literally no beach in front of that,” Martin said. “There’s a nice promenade to walk along and enjoy the sea air but there’s no actual beach at that place anymore.”

‘Soft Solutions’

Adding dunes and allowing kelp on the beach are “soft” or “green solutions,” Martin said.

“This is more of a nature-based solution that tries to work with nature, accepting the reality that nature is much stronger than any of us and trying to work with it rather than trying to fight it constantly,” Martin said.

Kelp is a natural organism that grows in the subtidal zone — the area below tide that is constantly covered in water except in extreme cases, Martin said. It is one of the fastest growing plants in the world. When storms or old age pull the kelp free, it washes onto the shore and provides not only nutrients to the beach but acts as a shield against erosion.

“Even if a bigger wave would come along, not as much erosion would occur because that kelp right there is holding it to some extent, kind of like a net up on the cliffs when they’re trying to stop the erosion,” Martin said.

While beaches such as Zuma Beach are cleaned, or groomed, of kelp for aesthetic purposes, Martin said leaving the kelp in the intertidal zone — the area between high and low tide, covered in various amounts of water — will help to leave the sand on shore.

“We’re better off if we have more kelp, not less,” Grisanti said.

L.A. County only grooms the upper part of their beaches and leaves the intertidal zone alone, Martin said. Some state parks do not groom their beaches at all.

In Malibu, Santa Monica and Manhattan Beach, there are projects focusing on restoring dune habitats, Martin said. These dunes will also help protect homes and roads from waves.

“Those are going to allow more of a native vegetation to come back and they’ll provide habitat for a lot of other critters,” Martin said. “Also, it is a way of storing more sand, allowing a little bit better replenishment naturally, rather than bringing in a big truck load of sand.”

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