Sea-level rise is often pointed to as the unbeatable culprit chomping away at Southern California’s most popular asset. But rising seas aren’t the only reason the coastline is disappearing.
Decades of development along the coast blocked sand flow to beaches. Local shores historically have had a helping hand from the federal government in staying wide and sandy, but that assistance, like the sand itself, has dwindled in recent years.
City officials in Newport Beach and Huntington Beach are concerned the U.S. Army Corps of Engineers has yet to funded the major sand replenishment project that for decades kept the northern section of Orange County’s coastline flush with sand, providing a buffer between the ocean and communities and protecting a major economic driver for tourism to the region.
“It’s harmful to our beaches to not replenish our sand. It’s just time to do it, it’s way overdue,” Newport Beach Councilwoman Diane Dixon said. “It needs federal funds.”
Huntington Beach and Newport Beach city councils in recent weeks have passed resolutions to show they still support one of the region’s biggest sand replenishment projects, the Surfside-Sunset Beach Nourishment Project. Typically undertaken every five to seven years since the 1960s, the project plants sand that the ocean currents and waves then spread along the 12 miles from Alamitos Bay to Newport Beach.
But because there’s been no federal funding, the project hasn’t happened since 2010. And the impacts are starting to show, local officials said, as the sea creeps closer to homes and businesses that could soon be, if not already, in danger.
“We need our rivers to deliver sediment to the coast. If we don’t have that, we have to truck it to fill in the beaches,” said Brett Sanders, professor of civil and environmental engineering at UC Irvine. Coasts aren’t just facing sea-level rise, they are facing it with shrinking beaches, he said. “It’s a double-whammy.”
Growing narrow beaches
In the 1920s, beaches along Southern California were naturally narrow, Sanders said.
“Some of the leaders realized the beaches were too small to meet the demand for tourism,” he said. “The development of harbors and ports for industry, the military and recreation all aligned with the need to grow the beaches to meet needs for the growing tourism industry.”
In the 1940s, dredging to make way for the Long Beach Harbor and the Seal Beach Naval Weapons Station helped put sand on nearby beaches, allowing for an expansive, sandy coastline in the decades that followed. Similar big beach sand deposits happened when the Newport Harbor and Dana Point Harbor were built.
“Basically these projects put a lot of sand on our beaches and created this excellent environment for tourism, recreation and all the things we love about the beaches,” Sanders said.
But why should the federal government be responsible for the region’s beaches?
The construction of engineered flood control structures by the United States Army Corps of Engineers in the San Gabriel River and Santa Ana River between the 1930s and 1950s reduced and prevented the natural transportation of sediment and sand down the rivers to naturally replenish sand.
In 1962, Congress passed the Rivers and Harbors Act, which required the Army Corps of Engineers to address the impacts of the constructed flood control structures on natural sand depositions.
This led to the first Surfside-Sunset Beach Nourishment Project, or Stage 1, in 1964, which deposited 1.5 million cubic yards of sand. It has been repeated about a dozen times since, at least until 2010.
“It’s been a pretty successful project,” Sanders said. “It’s a really smart way to manage the erosion for northern Orange County. You put sediment in one spot and everyone benefits.”
The planned Stage 13 project was supposed to happen in 2018, but “has been delayed indefinitely by the federal government due to a lack of funding,” Newport Beach staffers told their council members in a recent report. Why the lack of funding for the project hasn’t been made clear, they said, but the coastline between Anaheim Bay Harbor and Newport Harbor has experienced “noticeable and dramatic degradation.”
The sand has eroded to the point that homes in the Surfside community are threatened by winter storms and high tides, they said.
Newport Beach made national news last July when Balboa Peninsula and its beach parking lots, streets and homes were flooded with up to three feet of salt water when a high tide hit during a big swell.
“This was not the result of a large winter storm and it could be a precursor of what the new normal will be without the wide, protective buffer that beach sand provides,” Newport Beach officials said in their report.
Orange County’s northern coastal cities aren’t the only one with sand troubles.
Capistrano Beach in Dana Point and San Clemente have been sand starved for years. At Capistrano Beach, officials are looking at a “managed retreat” after waves battered and destroyed the shore, which hasn’t had a major replenishment for decades.
In San Clemente, officials have been working with the US Army Corps of Engineers for two decades to get a big deposit of sand – enough to fill a football field 15 feet deep – for their San Clemente Shoreline Project.
Last year it got a boost in funding with the federal government allocating more than $500,000 to move the $11 million project forward. Working in San Clemente’s favor is the protection needed for railroad tracks that run there along the coast.
Newport Beach leaders hope to see some movement for the Surfside-Sunset sand project. Already, costs have skyrocketed.
Typically the feds foot 67% of the bill and local agencies pay 33%, most of which is covered by grants. Newport Beach has already allocated nearly $160,000 for the project, Huntington Beach nearly $300,000.
But that was when the project was expected to cost $18 million five years ago. Now? The project estimate is more than $50 million due to the delays and the increased quantity of sand required to move, Newport Beach officials said.
Officials with the US Army Corps of Engineers could not be reached for comment, but a 220-page report by the agency’s Institute for Water Resources in 2018 gives an in-depth look at California’s eroding shoreline.
A combination of factors have resulted in shrinking beaches, the report says.
Dams were built for flood control, and water supply and sediment collection basins built to reduce sediment runoff. Cliffs and bluffs were armored to protect against erosion. Jetties and breakwaters were built to protect harbors and promote navigation. Rivers were channelized, or even paved with concrete, and navigation channels were created that serve as major sediment traps.
The result: About 40% of California beaches eroded in the early-to-late 1900s, increasing to 66% over the past 25 years.
Since the 1930s, an average of 1.3 million cubic yards per year of sand was placed to widen narrow beaches in Southern California, but those projects have decreased in the past 20 to 30 years, the report says, noting at risk from the erosion is billions of dollars in real estate and commercial properties, roads and railroads and the tourism industry.
No free beach
While sand replenishment is the preferred solution for protecting shores over hard structures, such as jetties or concrete seawalls, it also has disadvantages. Costs are high and the sand has to be re-nourish periodically, the Army Corps of Engineers report points out.
And that sand has to be mined inland before it can make its way to the coast – a total of about 50 million cubic yards of sand and gravel are removed annually through “streambed mining,” though it is unclear how much of that material would naturally make its way to the coast, the report notes.
Between 1984 and 2012, the state and federal governments together spent $93.5 million to place 13.4 million cubic yards of sand on Southern California beaches. Surfside Beach received 71% of that sand, or 9.6 million cubic yards.
On the flip side, the report quantified what a sandier beach could mean in terms of a town’s revenue: In San Clemente, one of the region’s smallest beach towns, a 50% increase in beach width could generate $3.1 million in consumer surplus per year.
One challenge to getting these projects off the ground is the red tape in working with multiple stakeholders, Sanders said.
“They are enormously burdensome to coastal communities to try and get these projects to move forward, especially in California because we have one of the most advanced coastal oversight systems,” he said. “But they all need different things. It’s really hard to get stuff done.”
The amount of money spent on beach stabilization across the country is billions of dollars, he said. In some areas, such as in New Jersey, beaches are rebuilt after a storm only to be hit hard again the following year.
“There are these projects happening year after year at great expense to the public, where maybe it’s best to retreat,” he said.
The solution is looking at who will benefit from the investments. For the Surfside-Sunset replenishment, Sanders believes it would be money well spent to maintain the beach.
“We have several cities along the coast that all have an increased quality of life, recreational values and those beaches are used by people across Southern California,” he said. “It’s not just beaches used by the elite, they are used by people throughout California.”
The sand also provides a buffer between infrastructure. If beaches are gone, so soon would be Pacific Coast Highway, buildings and homes and gas and sewer lines built in the ground.
Sanders enlisted a team of students to help create modeling that shows the rate of erosion along various areas of OC’s coast, with drone footage that shows how drastic the coastline is changing. Just last week, Sanders hosted a virtual talk about the changing coast.
What will happen in the future depends on the bottom line: how much it costs to keep beaches sandy verses how much coastal communities will lose if beaches keep shrinking.
“We’ve had these big coastal construction projects that have allowed us to have these big beaches, but they require investment in sand replenishment,” Sanders said. “In Southern California, there’s so many benefits to so many people, we should be looking at ways to sustain them and not just walk away.”
Source: Orange County Register