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On a typical Saturday, surfers precariously scale a seawall at Kewalo Basin and propel themselves into the ocean, sunbathers squeeze onto a narrow ribbon of sand along Kahala Beach that only exists at low tide, and tourists pack a shrinking plot of sand fronting the Royal Hawaiian Hotel in Waikiki held in place only by an artificial groin.

Oahu has lost one-fourth of its beaches and of those remaining, about 70 percent are eroding. If state and county officials don’t start working to conserve what’s left of the sandy shoreline, most of the island’s beaches could disappear by the end of the century, say scientists. 

“I think by mid-century we are looking at a future where we are down to just a handful of healthy beaches and by the end of the century those will be disappearing, or gone already,” said Chip Fletcher, a coastal geologist and associate dean at the University of Hawaii’s School of Ocean and Earth Science Technology, who is one of the state’s leading experts on beach erosion. 

Slide the red button at the the bottom left of the photo to watch the disappearance of Lanikai Beach between 1967 and the present. The 1967 photo is from the city’s archives; Civil Beat used a drone to photograph the same exact location 48 years later. 

Beachfront property owners erected illegal seawalls in Lanikai in the 1980s. The city later granted them after-the-fact permits. The walls have devastated this portion of Lanikai Beach, which has topped lists of the world’s best beaches.

The situation has become so dire that Fletcher and other scientists say that policy makers need to start thinking about how to coordinate an organized retreat from the shoreline and begin making hard decisions about which beaches are most worth trying to save.  

“Honestly, it doesn’t look promising if we continue business as usual,” said Dolan Eversole, a scientist with the University of Hawaii’s Sea Grant program. “Thus, we need to be realistic about what we can protect in the future. In 20 to 30 years, I think we are going to be entering triage mode and identifying the highest priority legacy beaches and doing everything we can to protect them.”

The famous surfing beaches of the North Shore and Waimanalo and Kailua beaches on the windward side, known for their powdery white sand and brilliant turquoise water, could top the list, said Eversole.

Government officials also need to adopt aggressive setbacks from the beach that take into account accelerated erosion rates spurred by global warming and sea level rise, and take a harder line against seawalls and other structures that harden the shoreline and erode the public beach, beach advocates say.

Erosion Expected to Accelerate

Decades of overdevelopment along the coast and the proliferation of hundreds of seawalls that protect private property, but cause the beach to disappear, have led to the loss of Oahu’s beaches, which are critical to the economy and marine ecosystem, scientists say.

Sand needs room to shift up and down the shoreline. But because homes and infrastructure such as roads have been built too close to the coast, beaches have been pinched and eroded. And as the rise in sea level has naturally occurred over the past century, beaches haven’t had room to move inland.

The situation is expected to worsen with man-made global warming, which is causing an accelerated rise in sea level. By mid-century, the erosion rate on Oahu is expected to double and the shoreline could retreat inland by as much as 40 feet by mid-century, according to a study released last week by scientists at the University of Hawaii at Manoa’s School of Ocean and Earth Science and Technology and the Hawaii Department of Land and Natural Resources. By the end of the century, the shoreline could retreat by 100 feet.

By comparison, the county only requires homes to be set back 40 feet from the shoreline — 60 feet for new construction.

“This problem is going to grow in magnitude and spacial diversity,” said Fletcher. “Beaches that have been pretty stable are going to begin to erode. Beaches already eroding are going to experience accelerated erosion. Beaches that have sand deficits because we have landscaped away the dune are going to be falling over the tipping point and experiencing dramatic erosion. It’s just going to get worse. I don’t see any upside or bright side to the future of our beaches.”

As Oahu beaches increasingly disappear there will be fewer stretches of sand for monk seals and sea turtles to haul up and rest, scientists say. As waves slam against seawalls, churning up the water like a washing machine, the nearshore water will grow increasingly murky. The reflection of the waves off walls also scours the ocean floor, degrading coral reefs.

Beachgoers will have fewer patches of sand to flop and surfers will increasingly be launching themselves from seawalls or steps that descend not onto the beach, but straight into the water.

Hawaii’s beaches also form the backbone of the state’s $13 billion visitor economy, supporting more than 170,000 jobs statewide, according to a 2010 report from the U.S. Geological Survey. Tourism supports more than 60 percent of jobs in Hawaii.

Legacy of Seawalls

Hawaii residents and government officials have known for about a century that seawalls and other structures that harden the shoreline spell disaster for beaches.

The dramatic erosion of Waikiki Beach due to seawalls and dredging made headlines in the local papers in the early decades of the 20th century.

In October 1928, an article in the Honolulu Advertiser reported on a $50,000 government plan to build groins along Waikiki to try to retain the sand.

“It was once a long deep stretch of shining white sand, the kamaainas say and the records of history will tell,” the article says.

But “the seawall spelled destruction to the beach sand,” the article continues. “While admitting the delight of the water temperature, the moonlights, the hula dances and the music boys, (tourists) complained that the beach itself — well, just where was it?”

However, the loss of natural sand from Hawaii’s most famous beach, which is now almost completely man made with imported sand and artificial groins designed to keep sand in place, didn’t halt the erection of seawalls along other parts of the coastline over the coming decades.

In the early 1970s, about 7 percent of Oahu’s 112-mile coastline was armored with seawalls and other structures, according to 2010 research published by UH researchers, Jack Kittinger and Adam Ayers, in the journal, Coastal Management. This number has grown to about 40 percent, even though the state and county began enacting strict permitting systems to limit seawalls in the 1970s.

And while some coastal states have outlawed seawalls, Honolulu continues to permit them.

Since 2010, the city has approved 19 seawalls and other structures within shoreline setback areas, according to data provided to Civil Beat by the city’s Department of Planning and Permitting. These are zones where by law no permanent structure is supposed to be built, but property owners successfully sought exemptions from the law.

Most recently, the city approved a new rock wall for Lee Kun-hee, the billionaire chair of Samsung Group who recently bought a Kahala home formerly owned by Japanese real estate tycoon Genshiro Kawamoto.

The city denied three seawalls over the past five years and also issued 65 notices of violation to property owners related to illegal seawalls and other hardening structures, according to DPP data.

Officials from Honolulu’s planning and permitting department didn’t respond to interview requests for this story or specific questions about whether the department had taken any recent steps to combat the problem of erosion and seawalls and whether they had formulated a long-term plan to address the issue. 

Holes in the Law

On the surface, Hawaii has strong laws in place to protect its public beaches, which are part of the public trust.

In 1964, the state created a conservation district which includes the state’s beaches and enacted rules to protect them from development. In the 1970s, Hawaii was also one of the first states to implement the Coastal Zone Management Act, a federal law aimed at managing coastal development so that it didn’t harm the nearshore environment.

Hawaii’s CZM rules emphasize the protection of the sandy shoreline.

“The Legislature finds and declares that it is the state policy to preserve, protect, and where possible, to restore the natural resources of the coastal zone of Hawaii,” according to the state’s rules.

A City and County of Honolulu ordinance also stresses the protection of public beaches over private property rights, stating, “It is the primary policy of the city to protect the natural shoreline.”

But in practice, Hawaii’s legacy of protecting its beaches has been poor, as evidenced by the dramatic and ongoing beach loss, say critics.

“The results are pretty horrific,” said Kittinger.

In their research, Kittinger and Ayers compared Hawaii’s shoreline policy to that of North Carolina.

They concluded that North Carolina’s overall policy was more effective, primarily because the state had outlawed what’s commonly referred to as the armoring of shorelines, building structures such as seawalls and revetments, or dropping boulders on the beach that protect private property.

“The result of that is if you or I were a millionaire and wanted to build a house on the beach, because we are not afforded the legal protection of armoring, we now have to assume the risk of losing our house,” said Kittinger. “And to me, that is very smart public policy.”

Hawaii has taken a different tack, he said: “The public loses the beach at the expense of the private landowner keeping their home.”

Hawaii and Honolulu laws allow beachfront property owners to claim a hardship exemption in order to get permission to armor their property. Because Oahu’s setback policies are inadequate and homes are built too close to the coast, this policy virtually ensures that every property will eventually have a seawall, said Fletcher.

A Path Forward

Oahu isn’t the only island suffering from beach erosion. Maui and Kauai have also suffered significant beach loss. But both counties in recent years have also adopted progressive setback policies for coastal development that take into account anticipated erosion rates.

Maui’s setback for constructing homes and infrastructure along the coast is 25 feet plus 50 times the erosion rate. Kauai’s setback is 40 feet plus 75 times the erosion rate. Kauai now also prohibits seawalls.

However, Oahu hasn’t followed suit. The county’s setback policy of 40 feet and 60 feet for new construction doesn’t take into account anticipated erosion rates.

With new research showing that the rate of erosion is expected to more than double in the coming decades, Fletcher said that the need to revise setbacks is all the more pressing.

DPP officials did not respond to a question about whether or not they planned to review their setback policy.

But Oahu has an even bigger problem: intense development has already taken place on much of the shoreline, ensuring continued fights between property owners seeking to protect their homes and the public and government officials seeking to protect the public beaches.

“The problem with our beaches is that the cat is already out of the bag because we have already developed many of our beaches,” said Fletcher. “We need to develop some sort of escape strategy for existing homeowners. There are no easy or inexpensive ways to retreat from the shoreline. It’s a huge thorny issue.”

One option could be to expand Oahu beach parks by acquiring adjacent private properties, said Fletcher. In return for donating property to the state, owners could receive a reduced tax or reverse mortgage.

But encouraging homeowners to donate highly lucrative beachfront property to the state could be difficult. Eversole said that the most realistic time to implement some sort of managed retreat from the shoreline may be after a hurricane or tsunami. Homeowners could be prohibited from rebuilding destroyed homes or given land makua of the shoreline to relocate to.

Recently, the Honolulu City Council and Legislature are exploring setting up funds for beach restoration.

The council is currently debating two bills that would levy assessments on about 6,500 Waikiki businesses in an effort to raise $600,000 annually to fund long-term beach management and replenishment at Waikiki. 

A bill that would set up a dedicated fund for beach restoration and conservation recently passed out of the Senate Ways and Means Committee. The bill doesn’t have an appropriation yet, but up to $5 million is expected to be diverted annually from the transit accommodation tax.

The Legislature also passed a law last year creating a Climate Adaptation Initiative. The consortium of state departments, counties and federal representatives are tasked with reviewing the science on beach erosion and coming up with recommended solutions to manage the shoreline.

Overall, Fletcher said that Hawaii needs to develop an overarching strategy for dealing with the realities of beach erosion, instead of the current fragmented and reactionary policies that have guided much of public policy for decades.

“We have been twiddling our thumbs and snapping our heels on this issue for decades now,” said Fletcher. “Beaches continue to fail. Erosion continues to eat away at our shoreline. And we have made no significant progress in terms of beach conservation.”

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