Bathymetry Project

Despite its longtime popularity as a local surfing treasure, much has yet to be discovered about what the ocean at WindanSea looks like below the waves — until now. The WindanSea Surf Club junior team, after nearly a year of planning, has embarked on a project to map the bathymetry (water depths in the ocean), reefs and characteristics of the floor at their namesake beach.

Using kayaks equipped with GPS technology and Lowrance sonar equipment and BioBase automated cloud-based mapping software, the teenage team went out for its first data-gathering trip July 23. WindanSea, between Palomar Avenue and Westbourne Street, is famous for its surf breaks created by the reefs below the surface.

“We couldn’t map the whole thing is one day, but we uploaded our data from the sonar equipment and found the gaps we missed,” said club member Madeline Perreault. “We’ll go back out to fill in the holes.”

Optimistic they can have the whole area mapped within a few trips, Perreault and the team will return to the sea in the coming weeks, when the surf is predicted to be small. With safety as the chief concern, the team partnered with the lifeguards to coordinate the best time to be out on the water (low surf for a smooth surface). When the bathymetry map is complete, the team will hand it over to lifeguards. “We’re giving the data to the lifeguards so they have a better idea of what the sea floor looks like,” Perreault. “Reefs are very complicated; there are deep spots and shallow spots, ridges and caves. While I hope it doesn’t happen, if someone goes missing or drowns, the lifeguards will have a better idea of where to look and what to look for.”

San Diego Lifeguard Lt. Rich Stropky said the information gathered by the teens will help with training purposes. “When we have new people assigned to WindanSea, we talk a lot about the surface, but the training doesn’t explain what’s going on under the waves and why the currents do what they do and how they operate,” he said. “There is a lot of interest in this project from our diving team. If (in the event of a rescue or dive) we can pull up a bathymetry map, it helps us direct and give folks better guidance.”

He added, “It will bring some science to the hydrology we’re talking about. Plus, it’s always cool to see a picture of what you’re swimming over. Overall, I’m stoked to be working with them. It’s great that they are focusing their energy on something that helps us.”

Steve Jenner, a retired business professor and team leader, explained that bathymetry is a key component to predicting tides, currents and riptides. “If you know the shape and contours of the bottom of the ocean, and you have the perimeters and details of the swell, you can put those two things together and make predictions,” he said.

Throughout the year, the swells and sand patterns change, so the team is considering seasonal mapping to see how the sea floor looks in the summer compared to the winter.

“We want this data to be available to anyone who would benefit from it — lifeguards, scientists, the community. We might even do a 3-D model or put the images on T-shirts,” Perreault said.

Jenner said while the WindanSea Surf Club typically engages in community service projects, when the idea came up to do something educational and beneficial for lifeguards, the teens were immediately on board.

They underwent extensive training to learn how to use the equipment to ensure accurate readings. During the first trip, a total of four teens went out in two, two-person kayaks. For subsequent trips, the team will go out in shifts so everyone can participate.

Jordon Shultz, who did not go out in the initial trip, said he’s looking forward to the next mapping outing. “When I get older, I want to get into environmental science and I love the ocean,” he said. “This project interests me because we can create this picture of what the bottom of WindanSea looks like. As a surfer, it’s cool to know what’s there.”