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Shannon Thornton

An Update on San Clemente's Sand Replenishment & How You Can Help



On May 31, the first stage of San Clemente’s 50-year, $14 million sand replenishment project drew to a close, resulting in the delivery of 140,000 cubic yards of sand to the beach area stretching from the pier to neighboring T-Street.


However, some locations are still devoid of the sandy beaches they desire, and this is leading some to wonder: what exactly is going on?

For the past decade the beaches in San Clemente have steadily eroded, though the last three years have proven the most dramatic.


Erosion along the Cyprus Shores neighborhood and the Cotton’s Point wave has been so extensive as that the beach, once 200 feet wide, no longer exists, and waves break right up to the railroad tracks currently owned by the Orange County Transportation Authority (OCTA).


According to the beach preservation and advocacy organization, Bring Back Our Beaches, the causes of erosion in San Clemente are largely anthropogenic and reflect the larger trend of Southern California, where the natural methods of sand replenishment have been suppressed as the region has developed.


Human interruptions in the forms of dams, upstream development, and stormwater management have drastically cut the onshore replenishment sources to San Clemente, those being the San Juan and San Mateo creeks, which historically provided an average of 40,000 cubic yards/year and 11,000 cubic yards/year, respectively.


The organization was also able to map out the rate of erosion in the town by using measurements dating back to the 1980s.


When plotted on a graph, a stable trend of size fluctuation is visible among the beaches from the 1980s until the early 2010s, when the San Clemente beaches began to erode precipitously. The tipping point occurs just around the time of Hurricane Marie.

It is important to note that coastal erosion is not a localized issue, but one that is constantly occurring around the world.


In Southern California there has always been a trend of beach erosion and regeneration; a strong storm may move sand away from a certain stretch of beach, but it has typically been brought back in due time.




The main courses through which sand is brought back and beaches are regenerated include sediment deposition from rivers (onshore sources) and offshore sand buildups carried in through swell and current movement.


This is the dynamic that characterizes most coastal areas, and the problem in San Clemente is arising due to impediments in the natural regenerative flux.


Since 2010, the beaches in San Clemente have been eroding without the vital component of natural replenishment, leading to the dramatic changes in beach size and the marked deterioration in wave quality observable today. Breaks south of T-Street, including Riviera and San Clemente State Beach, depend on sand placement to break correctly.


When there is poor sand buildup, the quality of the wave suffers.

Currently, OCTA supports the continued armoring of the railroad tracks fronting these waves, which is the placing of large boulders between the tracks and the ocean.


Besides a host of other maladies, armoring the coastline only serves to exacerbate the erosion by blocking the natural flow of sand and sediment while also creating a turbulence in the water that directs erosion down the beach and towards the end of the structure, causing more sand loss. 


Further south towards Cottons Point and the Cyprus Shore neighborhood is where San Clemente’s beach erosion is the most pronounced; it is also where the coastline is the most heavily armored.


There is no longer any beach in front of Cottons, and this allows the water to come right up to the train tracks and refract back out into the ocean, taking sand along with it.


This refraction, besides causing Cotton’s beach to disappear, also accounts for a noticeable diminishment in the quality of the wave, something local surfers have likened to a “perpetual high tide”.

Breaking over a cobblestone reef, Cottons used to consist of a fast right and a long, drawn out left that ended on the sand in front of former U.S. president Richard Nixon’s home.


Now, the Cottons left has no sand to break over, resulting in a wave that is so mushy and slow that, even on large days, it is either too soft to catch or challengingly bouncy, being hampered by the backwash that refracts off of the train tracks.


Unfortunately, most of the sand from the first phase of the replenishment project isn’t expected to make it down to Cottons, and the 140,000 cubic yards of sand which did make it to the beach is a slash from the originally planned amount of 250,000 cu/yds; this markdown is due to the delay faced early in the project. Originally planning to dredge sand from an offshore site in Oceanside, the samples taken found the bottom to consist largely of cobblestone.


In April 2024, after the next dredge site – near Surfside-Sunset, 30 miles away – was found and the process began, the project found its time limited, as the first phase of the project was planned to end before Memorial Day.


Currently, the replenishment project plans to deliver 250,000 cubic yards of sand to a 3,124-foot-long stretch of beach between Linda Lane and T-Street every six years for the next fifty, meaning that in 2074 there will have been 2-million cubic yards of sand accreted on to the beach.


The machinations of the project consist of a slurry mixture of dredged sand and water pumped through an underwater pipe on to the beach, where it is spread accordingly with the aid of heavy machinery.


Another advocacy group and organization, Save Our Beaches San Clemente, provide information on other types of sand replenishment and retention systems including groins (akin to the Newport Jetties), breakwaters, artificial reefs, and living shorelines. The group also provides information on San Clemente’s longshore drift patterns. 


While the sand replenishment has helped bolster the size of the Pier and T-Street areas, these were already the most stable beaches in the town, with the dominant longshore currents directing sand flow towards the area.

Recently, OCTA released their proposed plans for armoring the railroad tracks in front of San Clemente State Beach and the Cyprus Shores beach near Cottons.


The $200-million proposition calls for the seaward extension of boulders fifty feet wide for about a mile down the beach. If followed though, the results of this plan would occupy the entirety of remaining beach from State Beach to Cottons, as the beaches themselves are only fifty feet at their widest.


This plan would mean the end of these beaches. 

Just as San Clemente thought that assistance was finally in view, these plans arrive and threaten the extinction of some of the town’s favorite beaches.




For more information on the topic, you can visit Bring Back Our Beaches and Save Our Beaches San Clemente, and to sign the petition protesting OCTA’s proposed plans, visit here.

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