The devastating floods in Richmond Hill last year as a result of Hurricane Debby has led an area high school student to study stormwater management here.
Cathryn Martin, a senior at Richmond Hill High School, chose to analyze the effects of population growth and housing development on effective stormwater management as part of her year-long AP Research project.
“We started exploring our research topics at the beginning of the year,” Martin explained. “And around that time was when Hurricane Debby hit, and all the flooding happened.”
Martin, who’s lived in Bryan County “her whole life”, said that she knew friends whose houses were affected by flooding in subdivisions like Richmond Place and White Oak/Live Oak, and felt impelled to volunteer at the Richmond Hill Community Resource Center, helping distribute food and water to folks trapped in their homes.
“Just witnessing all of that [damage] personally made me wonder why the flooding was so severe,” Martin said.
Growing pains
When working on her project, Martin knew right away that she wanted to focus on rapid housing and warehouse development in the county over the years as a variable to be studied.
“I knew it all had something to do with all of the development [in the county],” Martin said. I’ve seen Bryan County grow all around me.”
Using open-source analysis software from QGIS, Martin created land use maps from 2008-16 and 2023 and examined key storms that affected the southeast region between those years, such as Debby in 2024 as well as Tropical Storm Fay in 2008 and Hurricane Matthew in 2016. She then used a flood amplification index to analyze the flooding from those three storms, dividing the Ogeechee River’s crest height by the amount of rainfall from each storm.
She then tracked the county’s growth in impervious surfaces, or hard, human-made surfaces that prevent or impede water flowing to the soil, such as sidewalks, parking lots, and rooftops. In her research, Martin found that the massive population growth in Bryan County--particularly Richmond Hill--over the past 15 years has concurrently led to an increase in impervious surfaces following rapid urbanization.
With statistical modelling, Martin was able to prove a positive link between a county-wide increase in impervious surfaces and flood severity, proving that impervious surfaces contribute to increased stormwater runoff, causing strain on local drainage systems like the City of Richmond Hill.
“It was good to put some numbers to [the issue] and see how it’s been affecting us with statistics,” said Martin.
What comes next
Although Martin’s project didn’t focus on solutions to this issue of more intense floods, her work cited the need for more research on flood mitigation strategies for communities, as well as better city planning and development that includes the need for environmental conservation.
In a class like AP Research, students like Martin are given the platform to research any given topic through “...analyzing and synthesizing information” and “employing ethical research practices” as they address their topic question, according to RHHS teacher Patricia Urso’s class website.
Martin recently defended her project in front of various science teachers as part of her overall grade this past March.