Stevens Doctoral Candidate Designs Artificial Reefs for Coastal Protection (USA)
For Spicer Bak at Stevens Institute of Technology, being a beach bum and a PhD candidate go hand-in-hand. That is because this Ocean Engineering graduate student studies beach erosion to better understand how to protect America’s coastlines.
Coastal protection is a major topic for government agencies, ocean scientists, and beach bums around the world. It’s also a big issue among surfers, one of the most vocal and engaged groups among beach users. As an avid surfer himself, Spicer makes it a personal mission to discover new ways to preserve beaches without reducing the chance of catching a wave.
“There is a great need today for a solution that preserves beachfront without damaging recreational value, and does so in a relatively natural and more permanent way,” reports Dr. Thomas Herrington, Spicer’s advisor and Assistant Director of the Center for Maritime Systems.
The solution proposed by Spicer and Dr. Herrington is the installation of artificial reefs designed to advantageously influence waves to protect seaside property yet maintain surfing potential. To develop these reefs, Spicer works on computer models and scale physical demonstrations of artificial reef schemes that will one day became permanent fixtures along popular New Jersey beaches. He is also one of several doctoral students who survey New Jersey beaches to better understand current erosion processes and how they are affected by storms, tides, and human activity.
Artificial reefs are meant to assist the common response to beach erosion today, called beach replenishment or beach nourishment, which is simply the adding of sand to widen or restore a beach. This relatively straightforward approach has its advantages: it starts working immediately and causes no problems to marine life as long the sand is mostly mud-free.
Despite these benefits, “Beach replenishment can ruin waves and regularly takes beaches out of commission because new sand has to be added again and again,” Spicer states.
A fundamental problem in nourishing beaches is that imported sands often have a different grain size than native sand. Adding sand with smaller grains causes sand to be easily swept off the beach, creating a mellow slope that requires the application of more sand to appropriately widen the beach. Larger grains cause steep slopes, which make waves break too close to shore creating dangerous shore break.
“There are only so many waves out there,” Spicer says, so when beach replenishment cuts waves in one part of the beach, surfers must jostle for smaller and smaller surfing spots. This isn’t only a concern for surfers, but also for businesses at destinations where visiting surfers and other beachgoers are a major economic factor.
Regardless of these disadvantages, beach replenishment is the only proven method for widening beaches. Artificial reefs that change beach conditions are a relatively new concept, but have become a hot topic in the surfer community after previous projects in Australia and southern California. Spicer is building on the data from those successes to create his own reef designs.
Spicer says he is “stoked” that he gets to combine engineering and a love for ocean in a career. “It’s almost like a romantic fantasy that I get to do research related to surfing.”
About the Center for Maritime Systems
The Center for Maritime Systems at Stevens Institute of Technology works to preserve and secure U.S. maritime resources and assets through collaborative knowledge development, innovation and invention, and education and training. Composed of four integrated laboratory activities and three support groups, this Center has become the world’s leader in delivering new knowledge, advanced technology, and education in support of the maritime community.
It uniquely integrates the fields of naval architecture, coastal and ocean engineering, physical oceanography, marine hydrodynamics and maritime security to create a trans-disciplinary enterprise that can address both the highly-specialized issues confronting each discipline, as well as the more complex, integrated issues facing natural and man-made maritime systems. The inclusion of undergraduate and graduate students in this collaborative research endeavor continues the Stevens tradition of Technogenesis® – where students, faculty, and industry jointly nurture new technologies to the benefit of society.
Source: stevens, November 11, 2011