CEE chair lauded for contributions to hydraulic engineering
Dr. Panayiotis "Panos" Diplas, the P.C. Rossin Professor and Chair of Civil and Environmental Engineering at Lehigh University, has been elected as a Fellow of the American Society of Civil Engineers (ASCE.)
The honor is given to practitioners and educators who have distinguished themselves as mentors and leaders in the civil engineering profession whose impact is felt on a global scale. According to the organization’s Web site, ASCE Fellows are individuals who have made "celebrated contributions and developed creative solutions that change lives around the world." The rank of Fellow is a prestigious honor held by less than 3% of ASCE’s more than 150,000 members in 177 countries.
"The Society's Fellow grade is intended to recognize members who have made celebrated contributions to our profession," says David M. Wieller, PE, President of the Lehigh Valley Section of ASCE (LV-ASCE) and a senior engineer with Borton-Lawson. "LV-ASCE was delighted to have the opportunity to nominate Professor Diplas for this honor. Through his teaching, research, and professional service, Panos certainly meets the standard."
LV-ASCE member Dr. Stephen Ressler '89G '91 Ph.D currently serves as an adjunct faculty member at Lehigh, and was also instrumental in shepherding Diplas’ successful nomination through the national process.
"Over the years, the ASCE Lehigh Valley Section has maintained a strong and productive relationship with the Department of Civil and Environmental Engineering at Lehigh," says Ressler, who previously served as Professor, Civil Engineering Program Director, Vice Dean for Education, and Chief of Staff of the U.S. Military Academy at West Point. "Panos’ selection as an ASCE Fellow is another wonderful milestone in this great relationship. We extend our hearty congratulations and sincere thanks for his continuing role in developing well-prepared future civil engineering professionals for the Lehigh Valley and the nation."
Diplas and the rest of the 2018 class of ASCE Fellows will be honored at the OPAL Gala on March 14, 2019 in Arlington, Virginia.
Why it matters how rivers behave
In Lehigh’s newly renovated Imbt Hydraulics Laboratory Diplas and his team study two river phenomena— scour and meandering—that have challenged engineers for centuries.
Scour typically occurs during major floods, when a river’s flow rises, kicks up sediment on the riverbed and transports it downstream. It is by far the leading cause of bridge failure in the United States.
"When sediment in the vicinity of a structure is mobilized," Diplas says, "a scour hole forms where the structure meets the soil. This, in turn, can compromise the structure’s integrity."
In one project, Diplas and his group are studying the movement of sediment particles. With support from the National Science Foundation and the National Cooperative Highway Research Program, they are attempting to determine the physical mechanisms responsible for scour development near structures. Their goal is to devise cost-effective scour mitigating measures that will allow bridges to withstand severe flow conditions.
Meandering occurs when rivers move and bend in seemingly random ways. It is a natural, healthy process, but scientists have not yet determined why a river meanders instead of following a straight path.
When a river meanders far outside of projections, says Diplas, a bridge built over a river can be isolated on a floodplain. It no longer performs optimally and can be compromised by an extreme event, costing money, time and even lives.
Human responses to meandering can upset naturally occurring conditions that sustain fragile river ecosystems, says Diplas. Fish populations have shrunk rapidly when humans manufacture unnatural conditions to counteract the effects of meandering.
Diplas takes a big picture approach to solving river-related problems and encourages students to look at water resource problems at the systems level.
"We tend to treat the symptoms rather than the disease," he says. "If you try to fix a problem by simply putting a bandage on it, you can make it worse or create more problems in the future."
About Panayiotis Diplas
Dr. Diplas and his research group study phenomena related to the dynamics of water, sediment and contaminant transport through waterways, floodplains and wetlands. His work is focused on the interaction of these components with the built environment, as well as with surrounding animal and plant life. Relevant research areas in his lab include environmental, fluvial, ecological and infrastructure hydraulics, sustainable development and hydrokinetic energy generation.
Across these areas, Dr. Diplas’ team develops theoretical understanding of empirical reality, solves real engineering problems by examining phenomena from a fundamental perspective, and uses state-of-the-art experimental facilities, computational, field and analytical techniques to develop better understanding of cause and effect relations. His group has pursued innovative research on the role of fluctuating turbulent forces on particle movement and other hydraulic phenomena, scour around bridge piers and abutments, design of in-stream structures, river mechanics and morphology, stream restoration, ecological hydraulics, wetland hydrodynamics and renewable energy.
Federal and state agencies that have supported Diplas’ research efforts include the National Science Foundation, U.S. Army Corps of Engineers, Environmental Protection Agency, Federal Highway Administration, U.S. Geological Survey, Defense Advanced Research Projects Agency (DARPA), and the Virginia Department of Transportation as well as its Department of Game and Inland Fisheries. Sponsors from industry and nonprofit organizations include Pacific Gas & Electric, Dominion Power, and The Nature Conservancy.
As chair of the department, Professor Diplas continues to teach courses in areas such as fluid mechanics, watershed management, and river mechanics, and is currently supervising the work of four doctoral candidates and a postdoctoral fellow. Over the course of his career, he has mentored close to fifty graduate students; seven of the Ph.D.’s minted in his lab currently serve in academia as faculty members, while others play leading roles in various government agencies and industry.
Before joining Lehigh in 2013, Diplas served on the faculty of Virginia Tech for 25 years, where he founded the Baker Environmental Hydraulics Laboratory and served as its director for 14 years. A previous recipient of the NSF National Young Investigator Award, Diplas has authored more than 80 publications in refereed journals, more than 85 refereed conference papers, 11 book contributions, and has given numerous invited lectures, keynote addresses and presentations at conferences and universities around the world. He has also served on the editorial board of many journals in his field, and has helped to organize two international conferences.
In 2015, Diplas was named a Fellow of the Environmental and Water Resources Institute, a branch of ASCE that seeks to advance water resources and environmental solutions. Previously, he has been named recipient of the H.A. Einstein Award from ASCE for significant contributions to the understanding of river mechanics, erosional processes and sediment transport. He is also a past winner of the ASCE Karl Emil Hilgard Prize, and has served as the Braun Intertec Visiting Professor with the University of Minnesota’s department of civil engineering.
