As any Charlestonian can attest, tidal flooding is a part of life on Charleston’s peninsula, which The Citadel calls home, but for biology major Grace Laws, ’26, there’s more lurking in the water than meets the eye.
Laws spent the last year investigating tidal f lood waters at three locations in Charleston alongside fellow Cadet Kamryn Peebles, under the guidance of Associate Professor Claudia Rocha. More specifically, they searched for evidence of Vibrio vulnificus, a pathogenic bacterium. “It’s most common in food poisoning,” said Laws, “but what we’re looking at is the way it can infect your bloodstream through open wounds.”
Laws and her fellow researchers tested flood water on Cedar Street, Market Street and Hagood Avenue during king tides— regularly occurring tidal events influenced by phases of the moon when the tide is especially high. While a regular high tide in Charleston reaches about 5.5 feet, a king tide can reach 7 or more feet, a difference that leads to significant road inundation, even without an associated rainstorm. “A king tide is huge,” said Laws. “Water can sit on the streets for a whole weekend.”
Laws worked to isolate the pathogen in the biology lab in Byrd Hall using a polymerase chain reaction test, a technique that amplifies DNA strands for easier analysis. The samples are then stored in nitrogen banks, which keep them frozen for future research.
For Laws, awareness of the problem is a crucial step toward solving it. “Unfortunately, all of our sample sites are located in under-resourced communities,” said Laws. “When a king tide comes in, people can’t even walk on the street to their house. The water is up to their knees. What is the effect of that? This research opens up those questions, and I think that’s important.”
Laws, a soccer player and Army ROTC scholarship cadet, plans to attend medical school with hopes of becoming an active-duty physician. “This research has really cultivated my interest in molecular biology and reinforced just how powerful these tiny things can be.”