Graduate student looks to inform coastal communities on how to respond to hurricanes
Growing up as a resident of New Orleans, Louisiana, civil and environmental engineering graduate student Nick Brilli has always had a love for the coast.
He was 9 years old when Hurricane Katrina hit the Gulf Coast and he was forced to evacuate his home for about three months. “I’ve experienced firsthand how devastating coastal storms can be and how important it is to develop engineering solutions to protect the people that live in vulnerable coastal areas,” Brilli said.
That vulnerability persists in the current hurricane season. After an active season in 2020, experts predicted another above-normal season in 2021, and coastal towns have braced for its impact. These extreme events threaten coastal areas with erosion and other geologic effects.
Since 2019, Brilli has participated in the U.S. Coastal Research Program’s During Nearshore Event Experience project in Duck, North Carolina, to help develop better methods for characterizing the erodibility of coastal sediments. The project brings coastal researchers from different universities together to collect measurements on the beach and in the nearshore.
Brilli has spent time in Duck doing field work to collect water content and bulk density measurements, as well as obtain estimates of sediment strength with a free-fall penetrometer, which is a probe that free-falls into the seabed to assess the strength of the bed.
The goal is to identify areas susceptible to erosion and where sediment is likely to deposit. While he was on the North Carolina coast, Brilli surveyed the beach daily, performing topographic surveys to measure bed-level change and water content. This year, he will also begin collecting physical samples from the beach to take to the lab, to determine erosion properties that will give a better idea of the measured geotechnical properties and bed-level change.
Brilli, who received his bachelor’s degree in civil engineering from Virginia Tech, decided to stay for graduate school to continue working with Anthony and Catherine Moraco Fellow Nina Stark in the Coastal Geotech laboratory, which studies coastal floods, erosion, and beach dynamics and trafficability. Stark is also an affiliate of the Center for Coastal studies at Virginia Tech.
“In one sentence, my research is focused on developing better methods for characterizing the erodibility of coastal sediments,” Brilli said. This involves many hours of field work to collect data and survey beaches. While this type of field work can be tedious, and he admits that he frequently needs to vacuum sand out of his carpets after analyzing samples, the data he is collecting as part of the DUNEX project will ultimately guide coastal communities by providing information to guide decisions related to safety and economics and develop strategies for coastal resilience.
“Most of the models and methods we currently have to predict erodibility focus on the interaction between the fluid and individual sediment particle,” Brilli said. “The goal of my work is to better understand how the geotechnical properties of coastal sediments can affect their mobility.”
These sediments change through daily occurrences such as winds, tides, and waves, or through extreme events like hurricanes. Hurricanes can raise water levels and allow tides to operate further onshore, which can threaten the surrounding coastal communities.
“My hope is that the work we are doing will allow us to provide better information to coastal communities on how the coastline is going to respond to coastal extreme events and processes associated to climate change,” he said. “If we can identify areas of the coast that are more susceptible to erosion during storm events, it will allow coastal managers, engineers, and community leaders to make more informed decisions about how to proceed with coastal protection measures.”