Heinz Stefan: A Career in Water Research
With retirement approaching in May, 2011, Heinz Stefan can reflect back on a career that has moved from handwritten equations to complex computer modeling, from tightly focused research to interdisciplinary collaboration, and has included education for thousands of Minnesota and international undergraduate and graduate students.
As a young student, Stefan wanted to study something that would allow him to keep his options open. “I chose civil engineering because it’s a field where you can do almost anything,” said Stefan. “You can do something abstract, like applied math, or you can mix concrete and build bridges. Best of all, you can work at a desk, in the lab, or outside. The field is wide open.”
He earned a civil engineering degree in Munich, Germany, and a hydraulic engineering degree in Toulouse, France, where he went on to get a doctorate in engineering. In 1963, he was offered a post-doctoral position at the St. Anthony Falls Laboratory (SAFL) in Minnesota, which where he could explore even more of the world.
“I had heard of Dr. Straub, the founder of the laboratory, and I came to Minnesota for one year and it turned into two. My wife came with me, and our first child was born here. He moved on to Berlin with his family and became Chief Engineer at the Water Resources Institute of the Technical University. After two years, SAFL Director Prof. Silberman invited him back to Minnesota to take a faculty position. Stefan packed his bags and his family and returned to Minneapolis to stay.
Advising and Teaching Students
In addition to research and service, educating and supporting students has always been an important focus at SAFL. Stefan contributed to this effort by co-advising 80 masters and 28 doctoral students. “The first Ph.D. student, Dennis Ford, was an outstanding undergraduate in aeronautical engineering, who worked as a draftsman at SAFL” recalled Stefan. “I asked him if he wanted to pursue graduate studies, and he began working on a computer model to simulate stratification in lakes and reservoirs.” Before he had defended his thesis, The Army Corps of Engineers hired this talented young man to work in an interdisciplinary group of researchers developing simulation models that are still in use today. He had several productive years in Vicksburg, Mississippi, then started his own company with several colleagues.
Several individuals who worked with Stefan as graduate students have stayed on and have contributed to the success of SAFL. “It’s gratifying to see individuals like John Gulliver, Miki Hondzo, Chris Ellis, Omid Mohseni , Jeff Marr and others here at the lab,” he said. “Chris was a great discovery for the lab. He has a knack for zooming in on the essentials of new laboratory, and field instrumentation.” Most of the former students have, of course, moved on to activities in academia, industry and agencies.
Stefan has had occasion to help develop educational programs and teach courses beyond SAFL and the University of Minnesota. These were either on the flow and potential ecological effects of cooling water from very large fossil-fueled or nuclear power plants on coastal, riverine or lake environments, or they were courses on water quality modeling. Such courses were very useful in developing countries and had been developed by Stefan at the UofM. He was invited to teach in India, China, and Brazil for weeks at a time. “A Chinese researcher to SAFL arranged a teaching tour, and I got to spend 11 weeks in China beginning at Tsinghua University and the Water Conservancy Institute in Beijing and moving on to the Yellow River and the Yangtze River Basin Commisssions as a visiting scholar,” recalled Stefan. “Personal connections led to some interesting activities.”
The Changing Face of Students & Technology
With changes in technology and culture, students have changed as well. “Especially undergraduate students are in a hurry to finish their degree program,” said Stefan. “Part of it is financial pressure because of the rising costs of an education. In addition, they want strong direction. They no longer want to learn by experimentation and trial and error. But I feel that practice still has a place in advanced engineering. “
New computational tools have changed civil and hydraulic engineering, greatly reducing the time required for design by trial and error. In the past, students might have spent a lot of time on analysis, sometimes graphical , and on calculations. Now students enter data into specialized software and computer programs generate graphical results right away.
Water Runs Through It
If there’s one strong theme that flows through Stefan’s research, it’s water resources issues, especially the issue of temperature change. Early in his career, he was involved with the A.S. King power plant on the St. Croix River at the Minnesota-Wisconsin border. Because increased water temperatures would affect fish habitat SAFL had been commissioned to study how the warm cooling water flowed from the coal-fired electric power generating plant back into the river. The goal was to be able to predict temperature changes and minimize the effect that the water temperature changes would have on the surrounding ecosystem.
In the 1970s, it was off to Monticello, Minnesota, where the U.S.EPA had built an outdoor research facility near the nuclear power plant, tagging fish and learning how they responded to temperature gradients in a channel environment with pools and riffles. In the 1980s he became an advisor to industry on thermal pollution in mountain streams from a pump storage plant in Virginia.
In the 1990s, concerns grew about the nutrients and eutrophication of lakes, but these concerns were soon overshadowed by worries of global climate change. Stefan became involved in a major simulation effort for the U.S.EPA and the USDA that focused on the potential effect of climate change on water quality and fish habitat in lakes in the U.S. Fisheries professionals in the country started to take notice of his work. In the end, Stefan’s graduate students had created maps that showed how climate change would cause habitat to deteriorate for cold water fish and expand for warm water fish.
As issues related to climate change came to the forefront, so did other questions related to urbanization, and Stefan’s research shifted to address these growing challenges. When so much land is paved over, where does the storm water go? As that water warms up, how does it affect the local ecosystem? And what about the road salt that melts snow and ice? How does the increased salinity affect local watersheds?“
Research on chloride and salinity in streams, lakes and groundwater is changing the way we think about snow plowing and salting of roads and parking lots,” said Stefan. “Already, research has encouraged many changes. Today there are salt symposia. Snow plow operators are strongly encouraged and may one day be required to get certified. Employed are new techniques with lower salt application rates. Road salt’s impact goes beyond the environment. It’s a business issue, a convenience issue, a public safety issue, and a liability issue.”
Changes in Technology and Research
Like all fields of scientific research, civil and hydraulic engineering have changed tremendously over the years. Technology has expanded. New data collection and design systems feed decision making. As technology develops, it’s easier than ever to see how all systems – human and natural – are interconnected. Those systems are vulnerable to political pressure and other forces that can stop progress with serious consequences. Yet old and new knowledge and technologies blend together to make research more complete. “Some big benefits still come from old installations,” said Stefan. “For example, some old hydropower plants still produce electricity at a lower cost than new generating plants.”
How have things changed at the University of Minnesota? “When I first came to SAFL, sanitary engineers from the Department of Civil Engineering were doing excellent work to clean up the Mississippi River,” said Stefan. Yet, their work was disconnected from what was happening at SAFL. Today we are more aware of each others contributions and the need to co-operate. “There were many people and groups that would have benefited from working together but ‘turf protection’ prevented it. Water research was divided into specific areas without overlap. But water quality ties together many fields. You can’t do water research in isolation. Today at the lab, we realize that we are all interconnected, and there is much more collaboration and interdisciplinary work.”
SAFL’s key to success is the way faculty, staff, and students have been allowed to adapt and grow. Over the years, research has broadened to address new challenges and problems, expanding beyond its roots in hydraulic structures. “Changes in the lab echo changes in the profession,” said Stefan. “We don’t just do model studies on spillways and dams. We’ve added fluid mechanics, sediment, water chemistry and biology to the mix. Computer simulations, sophisticated data acquisition and other new tools have been added to analysis and experimentation, but they have also made research more complex. This is especially challenging for students. There’s more demand to be interdisciplinary and students could easily spend 15 years on their studies instead of four.”
Looking Back, Looking Ahead
As Stefan prepares for retirement, it’s an ideal time for him to reflect back. “Getting the Hunter Rouse Award from the American Society of Civil Engineers was a big moment for me. I was very humbled,” said Stefan. “Getting the Distinguished Graduate and Professional Educator Award from the University of Minnesota also meant a lot to me. Teaching is providing opportunity, not just passing on information.
So what’s next? Stefan’s biggest challenge will be deciding what projects he’ll want to continue participating in even after his retirement. That and sorting through years and years of articles and memories in his office. “I’m looking forward to quiet with a cup of coffee, just going through the stacks and doing more writing,” said Stefan. “I’ll have more time to enjoy simple activities, the enthusiasm of the people at the lab, and continuing to learn something new.”