Loyola Marymount University’s John Petrie, assistant professor in the Civil and Environmental Engineering Department, is interested in how water flows through urban landscapes and the vital restoration of diminishing ecosystems. He specializes in fluvial hydraulics, an important branch of science and engineering focused on the behavior, movement, and application of water and sediment in motion, especially in natural systems such as rivers, streams, and flood management channels.
The restoration of ecosystems in urban settings is critical in helping to improve air and water quality, mitigating the urban heat island effect, supporting biodiversity, and enhancing the well-being of residents by offering access to nature, while also addressing the environmental impacts of urbanization. Restoration in highly urbanized areas such as southern California is particularly challenging due to the need to balance ecological benefits with flood risk and protection of infrastructure.
Petrie joined LMU Frank R. Seaver College of Science and Engineering in fall 2024, teaching courses in Fluid Mechanics, and Urban Water Systems and Stormwater Management. He brings real-world experience to his classroom having worked for the United States Army Corps of Engineers (USACE) as a civilian senior hydraulic engineer and engineering technical lead on large-scale aquatic ecosystem restoration and flood risk management projects.
“Beginning in spring 2025, I’m excited to invite students of all levels and other disciplines, such as biology and ecology, to participate in my research which will continue to focus on investigating urban rivers and the restoration of ecosystems locally,” Petrie said. “Southern California is the perfect place to do this research, and I know LMU students are interested in participating in hands-on learning opportunities in the field. This is boots-on-the-ground work that, while labor intensive, can be a lot of fun. We’ll visit urban rivers, do some site reconnaissance, collect data and measurements at field sites, learn to use tools of the trade, and return to the lab to learn analysis procedures.”
Petrie says this engineering work is especially challenging in urban settings like Los Angeles because of density and lack of space. For instance, the channels for some urban rivers were built long ago, can be relatively narrow, and have development right up to the river’s edge, as is the case with the Los Angeles River. Innovation is needed to engineer solutions to challenges such as flood mitigation, erosion control, environmental restoration, public safety, and adaptation to urban growth.
Prior to joining LMU, Petrie taught civil and environmental engineering courses at California State University, Los Angeles and Washington State University. He earned his Ph.D., master’s and bachelor’s degrees all in civil engineering from Virginia Tech University. A string bass player, Petrie also earned a Bachelor of Music degree in jazz performance from the New England Conservatory in Boston. As someone who is up for adventure and trying new things, Petrie worked for three years in Doha, Qatar teaching mathematics and science courses required for art students enrolled at VCUarts Qatar, a satellite campus of Virginia Commonwealth University.