Why do jetties have good breaks?
Ever wanted to eat some sand? The Wedge in Newport Beach, California, is serving up just that. This infamous break is a monster of a wave that attracts surfers and bodyboarders from all over Southern California, all hungry for a taste of its slabby perfection.
But what makes the Wedge so special? Why does it peak up so much more than surrounding breaks? The answer lies in the physics of wave reflection and interaction, all thanks to a simple jetty.
Now, let's imagine a jetty that is perfectly perpendicular to the beach, probably covered in bird shit and shellfish that you definitely should not eat (either of them please). When a swell approaches at an angle, it doesn't just pass by - it bounces off. This reflection follows Snell's Law: the angle of reflection equals the angle of incidence.
That reflected wave doesn't just disappear. It interacts with the rest of the wave that caused it, creating a "wedged" wave with concentrated energy. This interaction is what gives the Wedge its notorious size and shape.
On a big south swell, this effect can be dramatic. As each wave reflects and interacts with itself, wave heights can nearly double. The result? Those infamous Wedge bombs that have made many a surfer question their life choices.
It's not just about size, though. The wave interaction at the Wedge creates a unique shape that bodyboarders and brave surfers dream about. The reflected wave causes the incoming wave to jack up suddenly, creating a thick, pitching lip perfect for getting slotted - or getting drilled deeper than an oil rig.
Now, this is for a single wave. When you have a set or a bunch of waves in a row, you can get a secondary peak where the reflected wave from the first wave will interact with the second incoming wave. This is what causes the second peak up the coast from the jetty at the Wedge.
Jetties offer another benefit for surfers. Breaking waves push water towards shore, which has to return to sea to keep things balanced. Usually, this creates rip currents to the side of breaks. But a jetty forces this water to flow back out along its length. For surfers, this means an express ride to the outside on big days. Hug the jetty, and you'll shoot right out the back of the lineup. Hopefully.
The Wedge's reputation has grown far beyond SoCal. On big days, the beach crowd rivals any sporting event. Photographers lineup with long lenses, hoping to witness a gnarly wipeout or the fastest foam in the west. So next time you're watching Wedge videos or standing on the beach as it goes off, appreciate the physics at play. It's not just water and sand causing that shape; jetties do a lot of the lifting.
Understanding the physics doesn't mean you can handle a 15-foot Wedge day. But if you want to try, well, you do you. Just look at this thing.
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