For decades, communities facing shoreline erosion—and especially ones that rely heavily on tourism—have conducted a simple calculation: The wider and sandier a beach is, the more towels fit on it.
For San Diego, that idea turned into a $28.5 million project this fall to rejuvenate the county’s beaches. From Imperial Beach at the border of Mexico all the way up to Oceanside, an off-shore dredge sucks up sand to be blasted onto a dozen miles of shoreline. The region last undertook the same project in 2001. But like clockwork, as ocean currents and climatic changes impact the Southern California coast, it was time to do it again.
Officials from SANDAG, the county’s collection of local governments, took me on a tour of the operation, starting with the dredge. “There’s a lot of consideration in where we go to get new sand,” Captain Dick Roel told me. City governments and dredging companies generally want to avoid damaging kelp forests or coral beds, which can harm the local economy more than new beaches can help it.
From the dredge, a pipeline about half a mile long carries the viscous mixture of sand and water to the shore. A single dredge can spend months, 24/7, picking up sand offshore and pushing it onto the coastline.
Dredging is an old technology, but companies like Great Lakes Dredge and Dock, the company working on San Diego’s project, see super storms like Hurricane Sandy bringing new demand to their industry. After the storm battered the Northeast in late October, New Jersey Governor Chris Christie and local officials sought dredging to help with storm relief. Around the same time, Great Lakes’ stock jumped more than 20 percent.
I asked Roel if he thinks climate change might usher in a dredging boom. “There’s got to be,” he says. He points to shorelines in Florida and along Atlantic states that are seeking more and more dredging. Hawaii regularly replenishes sand to keep its beaches attracting planeloads of tourists. The country most quickly innovating new dredging technology? The Netherlands.
I had some more questions about dredging, particularly the ecological impact of sucking 5,000 cubic yards of sand off the ocean floor. Shelby Tucker, a senior SANDAG official working on the project, says that federal and state agencies review the quality of the sand boats can pick up. Environmental reports investigate the impacts of adding massive amounts of sand to beaches.
Back on shore, Lawrence Honma, a biologist overseeing the project’s environmental effects, tells me that most recognizable fauna like dolphins and sharks are smart enough to avoid getting caught up in the dredging arms. Less agile species like worms and other invertebrates aren’t. But dredged areas tend to bounce back to ecological health in a few years, which makes the process different from, say, cutting down ancient forests or blasting away mountains.
Considering the energy, time, and people power invested in the process, I wondered just how permanent building beaches actually is. “Unfortunately this is a short term fix, so yes, a lot of this sand will be spread across the region,” Honma admits. Yet to top officials in San Diego, if it keeps the beaches full of sunbathers for five more years, it will have been worth it.