Growing up in a city flanked by rivers, Phong Le is combining his lifelong curiosity about the natural world with his math and science skills to better understand water resources and quantify the risk of hazards such as flooding for humans and the environment.
Le, a computational hydrologist at the Department of Energy’s Oak Ridge National Laboratory, is helping develop unique, detailed simulations of watersheds — areas where all water drains into a common body of water. The models incorporate complexities such as varying soil and water flow characteristics, land cover and weather patterns, and how they influence what happens during storms.
The goal is to provide more accurate long-term predictions of phenomena such as flooding or drought and how they affect populations, infrastructure and ecosystems to inform decisionmakers. A better understanding of the risk is essential. The U.S. National Oceanic and Atmospheric Administration confirmed 24 weather-related disaster events in the United States in 2024 through November 1, with 418 deaths and losses exceeding $1 billion each. Of those events, 17 were severe storms and four were tropical cyclones.
Le has collaborated on two key hydrology projects in ORNL’s Environmental Sciences Division since his arrival at the lab in 2022. The first is the IDEAS-Watershed project leveraging data science, machine learning and advanced modeling to better simulate watersheds at a large scale, supporting the management and protection of water resources.
IDEAS focuses on community-driven software development and provides training and outreach to promote adoption of the model for more accurate representation of waterways, with a goal of protecting water for energy production, human use, agriculture and ecosystem health.
Le is also working on a large collaborative effort focused on understanding and mitigating the impact of severe storms and examining air quality in the economically important area of Beaumont-Port Arthur in Texas, as part of the DOE Southeast Texas Urban Integrated Field Laboratory, or SETx UIFL. For that project, Le is focused on achieving a better understanding of how hurricanes and resulting flooding may affect the region in future years.
Le worked with ORNL colleagues to develop a framework for flood modeling that provides improved estimates of frequent and rare flood events as part of the SETx UIFL. By modeling the physical processes that transform rainfall into runoff and inundation, the framework accounts for factors such as land cover, infrastructure, soil properties and slope of the land. These elements, incorporated alongside population density data, provide a unique perspective on flood risk for humans.
“These are important modeling capabilities that significantly move our science forward,” Le said. “While we are specifically using the framework to study Southeast Texas, our results are generalizable enough to be applied to other areas of the country.”
Le noted how the collaborative nature of his work at the lab has driven his success. “It’s a team sport, our research here at ORNL. I’ve had a chance to learn from great people across many different fields,” he said.
ORNL’s supercomputing capabilities were a major draw in his decision to join the lab. “I first heard about the lab when I was taking a class in parallel computing algorithms as a graduate student at the University of Illinois,” Le said. “That was when the Titan supercomputer was the fastest here, and I was amazed by it. I recall thinking it was something like a dream come true. ORNL’s supercomputers provide the compute power I need to run the complex simulations we’re developing to understand water resources.”
River-watching stokes a young scientist’s curiosity
Le grew up in Hanoi, a city whose name translates to “inside the river,” as its 8 million inhabitants reside largely along the banks of the Red River in Vietnam. His father, a meteorologist who is now retired, spent his career studying and communicating about weather in the sprawling urban and agricultural region. He also encouraged his son to study Earth science in college.
“When I was very small, I liked playing outside, watching the river flow by, and was curious about where all that water was coming from,” Le said. “People said it came from the headwaters, but I didn’t know where that was. When I grew up, I came to realize that river flow was a cycle in nature with no real starting point. Even today there are many phenomena influencing rivers that I am still curious about and working to better understand.”
After earning his undergraduate degree in hydrology from Vietnam Water Resources University, Le spent three years as a researcher at the Vietnam Institute of Metrology and Hydrology. But as his science grew more complex he realized he needed to pursue additional studies.
Le earned master’s and doctoral degrees in civil engineering from the University of Illinois Urbana-Champaign, where he studied under a Vietnam Education Foundation Fellowship — a program created by the US Congress to strengthen the relationship between the United States and Vietnam through educational exchange activities. His doctoral thesis focused on an area of hydroepidemiology, studying how hydrology affects the life cycle of the mosquito and resulting mosquito-borne diseases such as malaria and Dengue Fever. Afterwards, Le spent three years conducting research and teaching at Vietnam National University.
Le was then hired as a postdoctoral researcher at the University of California Irvine, where he worked with Efi Foufoula-Georgiou, a distinguished professor who is considered a global expert in hydroclimatology and geomorphology. It was at UC Irvine that Le enhanced the skills he leverages today at ORNL.
Le said he is personally motivated by helping identify the risks that extreme weather events pose for humanity. “I’m interested in applying different techniques to understand the mechanisms driving these changes and how we can use science to help people prepare for it.”
His advice for young scientists? “Follow your own career path rather than chasing the hype,” Le said. “Don’t be afraid to tackle fundamental problems, even if your discoveries may go unnoticed at first. In the long run, you’re laying the foundation for your future career.”
UT-Battelle manages ORNL for DOE’s Office of Science, the single largest supporter of basic research in the physical sciences in the United States. The Office of Science is working to address some of the most pressing challenges of our time. For more information, please visit energy.gov/science.
This Oak Ridge National Laboratory news article "Phong Le: Exploring the rising tide of water resource risks" was originally found on https://www.ornl.gov/news
