Making Waves or Creating Havoc

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A Planned Jetty Extension in Carlsbad Revives the Beach Structure Issue in San Diego

By Patrick Zabrocki

NEWSFLASH: The surf at Tamarack in Carlsbad has been spared destruction, for now.

The Encina Power Plant announced in February that it would cease an application for a permit to extend the northernmost jetty and additional 200 feet at the outlet of Agua Hedionda Lagoon. The power plant, which uses the lagoon's water for cooling, says the jetty extension is a way to reduce sand buildup in the lagoon. However, the Encina Power Plant states that it is pulling its permit application because the jetty extension doesn't appear to be critically needed right now.

Fears that a regional sand replenishment project would fill up the lagoon with sand and require more dredging than normal convinced the Encina Power Plant officials to submit the jetty extension request several years ago. That regional sand replenishment effort put two million cubic yards of sand onto 12 beaches from Imperial Beach through Oceanside, but the power plant has not had to dredge any more frequently than its normal two-year cycle. The expensive and controversial jetty extension project was cancelled.

BUT WAIT A MINUTE ... Don't jetties make good waves? Is the dropped project a good or bad thing? Shouldn't surfers WANT to have a bigger jetty? ANSWER: NO! Simply put, jetties interrupt the natural cycle of beach processes and do more harm than good.

Waves of Change

Although there is a consensus among surfers that jetties create good waves, surfers should be happy that the extension project has been dropped. The environmental impact report for the Carlsbad jetty project had confirmed that the surf in the area would be significantly altered.

The big question is, "Would the waves in the area change for the better?" Nobody could know until after the jetty was built, and there would be a definite possibility that the surf could change for the worst.

There is a myth that all jetties make good waves. The truth is that sand makes good waves. The more sand you have the better the wave will be, generally speaking. Because jetties trap sand there is a chance that a good wave could form.

The important thing to remember about jetties and piers is that as permanent structures, they block a natural system of water and sand flow. As creatures of the environment, surfers must realize that messing with Mother Nature's plan only leads to disaster.


How would Tamarack break if the jetty on the left was extended another 200 feet...?

Environmental lawyer and past-Chairman for the San Diego Surfrider Foundation, Marco Gonzalez, says, "In my opinion, there is no excuse to place development where it will negatively impact a surf break. The waves at 'Middles' and 'South Jetty' break on a variety of swells year-round. To extend the jetty in such a way as to possibly eliminate both of these breaks is irresponsible and immitigable."

Cabrillo Power wants to extend the jetty to alleviate the cost of dredging, but as Marco points out, "The only reason it makes economic sense to build out the jetty is that they haven't quantified the cost of losing a surf break. They can continue to bypass the sand as they have all along. If they factored in the millions of dollars that wave is worth to local surfers, the jetty extension wouldn't make economic sense ... just like it doesn't make environmental sense."

Coastal Processes 101

When talking to other surfers, I have found a lack of understanding when it comes to permanent structures along the coast. The biggest misconception is that structures, such as jetties, actually make waves. One, or two waves at the most can be generated once the jetty is built BUT, because the jetty disrupts the natural flow of sand down the beach, it actually ROBS the rest of the beach of the sand needed to make other good surf spots. When it comes to good waves, it's all about the sand.


Sand accumulates on one side of the jetty and is robbed of sand on the other.

Currents and the Littoral Cell

The overall engine that creates and maintains the sand on beaches is the waves and tides. They create movement in the ocean that stirs up sand in the water. Waves come in and break at an angle to the beach and, with their momentum, transport the sand along the shore with the help of longshore currents.


Rip currents then take sediment from the surf zone and deposit it off shore. During the winter a lot of that sand it carried offshore by the large powerful currents created by northwest swells but some of "lost sand" is pushed back by the south swells during the summer, which is why we see seasonal sand amounts on the beach. The whole process takes place within a geographical area called a "Littoral Cell".

There are several Littoral Cells along the California coast that vary in size and function. One of the most studied littoral cells in the world is the Oceanside Littoral Cell here in the San Diego region. The Oceanside Littoral Cell spans the coast from Dana Point in the north to La Jolla in the south, a distance of 84 km (52 mi). There are two major sinks, Oceanside Harbor and La Jolla Submarine Canyon where large amounts of sand are pulled offshore by currents and deposited.

Sand transportation in the Oceanside Littoral Cell varies depending on the wave climate but measurements of net transportation rates may range between 50,000-100,000 m3 (65,000-130,000 yd3) per year (by comparison, a large moving van has a volume of about 200 cubic yards).

GOT SAND?

Beach sand comes from two main sources 1) bluff erosion and 2) river sediment. Wave and wind action erode coastal bluffs and deposits sediment on the beach and rivers/streams carry sediments from inland erosion onto the beach. These sediments are then are carried downstream by the currents in the Littoral Cell and make our beaches what you see today.

THE BIG PROBLEM starts when people decided to build dams upstream, thereby stopping the sediment flow from inland sources. We have also been hardening the coastlines with seawalls and development and preventing the bluffs and coastlines from eroding and becoming part of the beach.

Basically, people are stopping sand from getting to the beach.

Judging Jetties

The Littoral Cells transport sediment down the coast and to our surf breaks through currents but when people put permanent structures in the way of that transportation, such as a jetty, a buildup occurs. Imagine what happens when a four-lane freeway goes to a one-lane street. Everything gets backed up one side of the jetty while on the other side the beach gets thin and surf breaks are robbed of the sand that makes them good.

By building jetties, people are messing with the natural process and our beaches suffer. If you think Oceanside, Ponto, OB and other jetties are good breaks; just imagine what the other breaks would be like if we had a full flow of sand down the coast. In addition to surfing, below is a list of a few OTHER reasons to care about having healthy sandy beaches:

→Beaches are a huge financial asset for California. In 2001, beach tourism amounted to $61 billion, more than twice the value of the state's agricultural output.

→Beaches are a recreational destination for 67% of Californians every year, a higher percentage than any other outdoor activity.

→Beaches give us beauty and nourish our spirits.

→Beaches provide diverse habitats for invertebrates, shorebirds, and marine mammals.

Next time you look at the beach and see a pier, a seawall or a jetty, remember that those structures are messing with the quality of our coasts and degrading our level of surfing by depriving the breaks of precious sand. An extension of 200 feet to the jetty at Tamarack is messing with how the beach works and further degrading the surf.

To get involved in creating healthy beaches visit:


The San Diego Surfrider Foundation
Scripps Institution of Oceano

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