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Eroding bluffs could send California homes tumbling into the ocean. What can be done?

Pismo Beach
Credit: Pixabay/CC0 Public Domain

Over the past 30 years, Tony and Marilee Hyman have enjoyed the fruits of what they describe as "10 years of doing three jobs" to retire in their Shell Beach dream home.

Their home on Indio Drive just north of Pismo Beach proper is perched on a bluff more than 25 feet above sea level, with a lush garden backyard standing between their living room and the open ocean.

But even as little as 10 years ago, the Hymans had more backyard than they do today. The property has been victim to pounding and storm runoff that have eaten away at the coastline over the past few years, Tony said.

They and other oceanfront homeowners have found themselves on the front lines of a fight against the worst of Mother Nature's appetite, and in many cases, state regulators are siding with nature on whether it's better to protect valuable property by armoring the coast or give way to the inexorable forces of the sea.

Luckily, the Hymans already have a seawall protecting their backyard—but their neighbor to the north, John Okerblom, was denied permits to similarly armor his property. This unprotected property has allowed the crashing waves to work their way around the back of the Hyman's seawall and erode the bluff once protecting the side of their home.

"As this erodes, it's getting closer and closer to us," Tony said of the neighbor's property. "It's now down to 26 feet, where at one time it was more than 50 (feet)."

The Hymans' property was equipped with a seawall when they purchased the property for around $1.16 million in the early 1990s, Marilee said.

She said they partnered with Okerblom about five years ago to apply for the necessary permits to extend their seawall and build one in their neighbor's backyard but have been denied by the California Coastal Commission at seemingly every turn.

On Jan. 10, the Coastal Commission sent a letter to the Hymans making clear that any future armoring of the coastline along their neighbor's backyard would be prohibited—even if it means leaving their home at risk.

"In light of the dangers to development at this site, we advise that you pursue courses of action associated with this site that do not include shoreline armoring, and that you start planning for next steps that might be necessary in light of such dangers at this location, including potential removal of any threatened development before it falls to the beach below and creates public hazards," the letter read.

The commission's hard-line stance against seawalls has displeased some in the Shell Beach community. Homeowners want to protect their homes from falling into the ocean while the Coastal Commission says such armoring is too harmful to the environment to justify.

"I wish they would just come out and say it: They don't want private property on the coast," Shell Beach homeowner and Central Coast home developer Gary Grossman said of the Coastal Commission. "For now, (my house is) protected and they better have a darn good reason to deny me that right."

Coastal Commission, experts warn of environmental harm caused by seawalls

Coastal Commission staff said they do have a good reason for denying seawall permits requested along Shell Beach's coast: protecting the environment.

Seawalls cause beaches to "drown," said Kelsey Ducklow, the Coastal Commission's coastal resilience coordinator.

When a bluffside is armored, it stops the normal erosion processes that would otherwise allow the bluff to move backward as the oceans rise. This causes the beach area—enjoyed by people for recreation and animals for habitat—to slowly disappear, Ducklow said.

"It is unfortunate that so much of the development boom in California was at a time when we just didn't know about sea level rise," Ducklow told The Tribune. "But moving forward, we have to understand that the coastline is dynamic. ... So even if we attempted to protect every single piece of development that's along our coast right now—you can't protect it in place forever, no matter what we did."

In Shell Beach, the cliffs are eroding at average rates of at least 4 to 7 inches every year, according to Gary Griggs, a professor of earth sciences at UC Santa Cruz. However, most bluff erosion is "episodic," Griggs noted, meaning you could lose 10 feet of bluff in one year, and none the next.

Although not quite clear yet, it's possible that climate change caused by excessive fossil fuel emissions could be worsening bluffside erosion in areas such as Shell Beach, Griggs said.

This kind of coastal erosion is mostly caused by two factors: waves crashing against the bluffs and storms pouring water over and through them, Griggs said. Particularly in El Niño years when larger storms are more likely to hit the Central Coast—bringing massive waves and torrential rainfall—bluffs can erode quite quickly, he added.

"The major damage we've seen in the last half-century has been because of these storms, and it is not because of a few millimeters (of) sea level rise," Griggs said. "Until probably at least mid (21st) century, it's going to be these short-term, extreme events that are going to be the most problematic."

Overwhelming scientific evidence indicates that as the planet's climate changes, extreme storm events are likely to become more frequent and more damaging. Studies have even shown how winter waves along California's coast are getting bigger.

"When we armor the coast, we're basically making a decision to lose the beach," Griggs said.

Can armoring alternatives fill the gap?

There are alternatives to constructing seawalls along the coast, including erosion control measures and drainage fixtures. But those measures only slow—not stop—the problem at hand.

Another alternative, called managed retreat, is one that Shell Beach residents told The Tribune they feel the Coastal Commission favors. The concept involves moving homes and other infrastructure inland away from the eroding bluffs.

"It's not necessarily that we're advocating for managed retreat, or prioritizing managed retreat specifically, so much as it is one of the best ways to ensure that we can protect beach areas," Ducklow said of the Coastal Commission's stance. "Over the longest timescales, in some cases, it is going to make sense to retreat from the shoreline."

"And that's true not just to protect the beach, but also to protect those homes, all of that infrastructure," Ducklow continued. "We don't want to be in a time X number of years from now where we're spending millions and millions of dollars to continuously repair infrastructure, repair homes (and) repair or armor roads."

Managed retreat is difficult in a neighborhood such as Shell Beach. Homes with little to no front yard space directly abut roads that are lined on the other side with more homes, businesses and eventually Highway 101.

Legislators have attempted to create loan programs to help local jurisdictions buy homes at risk of falling into the ocean. In one veto of such a bill, Senate Bill 83 proposed by Democrat Sen. Ben Allen of El Segundo in 2021, Gov. Gavin Newsom noted that more work needs to be done before such a program could be implemented.

"Financial tools, such as the one proposed in SB 83, have the potential to play an important role in a portfolio of strategies that will help build coastal resilience in California," Newsom wrote in a letter to legislators about his veto of the bill. "However, such an effort should be considered within a comprehensive lens that evaluates properties to be included in a statewide plan."

The city of Pismo Beach and the Coastal Commission alike are now trying to figure out comprehensive solutions to those homes that get closer to falling into the ocean each year.

Pismo Beach is currently updating its local coastal program, the planning document that guides on development and protection of coastal resources.

The new local coastal program, which must be approved by the Coastal Commission, will likely closely align with the commission's language on seawalls, the city's new community development director Scot Graham said.

That process is still in the early stages, Graham noted, and he hopes there will be a public meeting in the spring to discuss the best steps forward for updating the city's local coastal program.

"It sits squarely right on private property rights issues versus preservation of our beaches and our ecological systems that are along the coast," Graham said. "Those things are both valid: People should have a right to protect their property, probably not to the disadvantage of our ecosystems and our beaches, because that's what makes this place nice."

"What's the line (between those two things)?" Graham asked. "We're trying to figure that out."

Lawsuit could decide future of shoreline armoring in CA

Grossman, the Hymans and Graham are hoping a clearer line on managed retreat will be drawn by a coming ruling in a San Mateo County Superior Court case between bluffside residents of Half Moon Bay and the Coastal Commission.

In the summer of 2019, the Casa Mira Homeowners Association sought to armor a stretch of coastline near a condominium complex, apartment building, sewage line and California Coastal Trail segment but were only authorized by the Coastal Commission to build 50 feet of seawall to protect the apartments.

The association filed a lawsuit against the Coastal Commission, arguing that homeowners had a right to protect their property under the 1976 California Coastal Act, which allows for the protection of "existing structures."

After releasing new sea level rise policy guidance in 2015, the Coastal Commission started arguing that the Coastal Act defines an existing structure as buildings and development in place before 1977. This makes it difficult to maintain an unbroken stretch of armoring along bluffs in danger of collapse as some homes were built after 1977 and therefore do not qualify for seawall protection according to the Coastal Commission's policies.

Though his home on Indio Drive has been protected by a seawall constructed in 2003, in 2020 Grossman discovered a cave forming under the bluff his home sits on as a result of unarmored parts of the coast, putting the property at risk of "catastrophic collapse." The Coastal Commission accepted his application to fix his seawall in February 2023 but added a $1.3 million "mitigation fee" to account for the environmental damage wrought by the armoring.

Grossman argued that by tacking on hefty fees and repeatedly denying proposals to repair and improve seawalls against future erosion, the Coastal Commission appears to be sending a clear message to smaller cities such as Pismo Beach: Seawalls aren't welcome.

"Everybody is waiting on Casa Mira" to set the standard for how cities, homeowners and the Coastal Commission can deal with bluff erosion, Grossman said.

"One of the ironies of it is they're (the Coastal Commission) going after very small coastal communities that are visitor-serving—exactly what the Coastal Act is supposed to promote," Grossman said.

Coastal Commission staff told The Tribune that they don't want anyone's home to fall into the ocean, but, as the law stands now ahead of a ruling in the Casa Mira lawsuit, seawalls are not the solution because of the environmental impacts.

"It's not that we're saying you have to pack up and leave, it's that armoring is not a permissible approach to address your concern," said Kevin Kahn, the Central Coast District manager for the Coastal Commission. "This is one aspect of that's just creating a lot of urgency around figuring these problems out."

2024 The Sacramento Bee. Distributed by Tribune Content Agency, LLC.

Citation: Eroding bluffs could send California homes tumbling into the ocean. What can be done? (2024, March 14) retrieved 16 July 2024 from https://phys.org/news/2024-03-eroding-bluffs-california-homes-ocean.html
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