Charles R. O'Melia, one of the world's leading water-treatment researchers who during his nearly-three-decade tenure at the Johns Hopkins University mentored more than 100 graduate environmental engineering students, died Dec. 16 of a brain tumor at his Timonium home.
He was 76.
"A true scholar and a gentleman, Charlie embodied the best of Johns Hopkins. His generosity and warmth of spirit were matched by a terrific dedication to his work as a researcher, educator and scholar," Nicholas P. Jones, dean of Hopkins' Whiting School of Engineering, and Edward J. Bouwer, chairman of the department of geography and environmental engineering, said in a joint statement.
"Charlie had a tremendous impact on the department, university and the field of environmental engineering, and his passing is a terrible loss," said Drs. Jones and Bouwer.
The son of an accountant and an elementary school educator, Dr. O'Melia was born in New York City and raised in the Bronx and Brooklyn.
He credited his mother with inculcating in him an appreciation for water on vacation trips to New Jersey beaches, Pocono Mountain lakes in Pennsylvania and Penobscot Bay in Maine.
He was 16 when he graduated from New York City's La Salle Academy.
Dr. O'Melia's youthful fascination with New York's bridges, tunnels, skyscrapers and infrastructure initially led him to pursue the study of civil engineering at Manhattan College. He later was drawn to the emerging field of environmental engineering.
"It just seemed more intellectually challenging at the time," Dr. O'Melia told the Johns Hopkins Gazette in a 2000 interview. "It allowed me to do something that involved serving the public."
He earned a master's degree in 1956 in environmental engineering at the University of Michigan, and a doctorate in environmental engineering in 1963, also from Michigan.
Dr. O'Melia began his professional career in New York City with an engineering consulting firm. He later taught at the Georgia Institute of Technology and conducted further research at Harvard University, until 1966, when he joined the faculty of the University of North Carolina.
While at UNC, Dr. O'Melia collaborated with his first doctoral student in 1971 and a third researcher in an effort that resulted in a highly influential paper, "Waste and Wastewater Filtration: Concepts and Applications," that detailed particle activities in the water filtration process: interception, sedimentation and diffusion.
Because of the paper, the U.S. Environmental Protection Agency established rules for removing harmful particles and microbes from water.
"Charlie had to push to protect water, and his work was fundamental in how we designed and operated water-treatment plants back in the 1960s and 1970s," said Dr. Bouwer. "This was pioneering work. His models and methodology have really stood the test of time and are still being used today."
In 1980, Dr. O'Melia arrived at Hopkins, when he joined the department of geography and environmental engineering in the Whiting School of Engineering, where he spent the next 27 years, including two terms as department chair.
During that period, he also mentored numerous master's and doctoral students, many of whom went on to become prominent professors at other universities and colleges as well as leading figures in government and private engineering.
"Working with him was clearly the best professional decision I have ever made, and it has changed my life in extraordinary ways," said William C. Becker, who had been one of Dr. O'Melia's doctoral students and is now vice president and director of water process technology and research at Hazen and Sawyer, a New York consulting firm.
"As a teacher, Charlie was simply extraordinary. He is one of a handful of people that can be called a 'father' of modern drinking-water treatment," said Dr. Becker.
"He had a way of explaining very complex material in terms that were understandable. More importantly, he taught his students to always look at problems in terms of first principles, but to also always keep an eye on the big picture," he said.
"He was very patient and supportive, had incredible insight and was a phenomenal role model," Dr. Becker said. "In addition, Charlie is perhaps the most humble person I have ever met, always giving credit to others. He will be sorely missed by me and the entire profession — he simply is irreplaceable."
Dr. O'Melia was named Abel Wolman Professor of Environmental Engineering in 1999.
In 2005, Dr. O'Melia was honored by Environmental Science and Technology in a special edition of the journal that called attention to his studies of how particles behave in water and how best to remove them.
"Charlie was almost introverted and quiet," said Dr. Bouwer. "He was both personable and humble."
In 2000, when Dr. O'Melia was presented the Athalie Richardson Irvine Clarke Prize, one of the top awards in the field of water-related research and technology, it came with a gold medallion and a $50,000 award.
"I'm going to keep the medallion and give away the money. If I'd won the lottery, I wouldn't give all of that money away," he said at the time. "But this was an award associated with some of the work I've done. And I didn't want to profit from it. I wanted to recognize some of the places that have helped my wife and I get here. It was a team effort."
Away from Homewood, Dr. O'Melia was a member of the EPA's Science Advisory Board and had chaired committees for the National Research Council, including one a decade ago that studied New York City's drinking water. He also was a consultant on a project whose goal was cleaning up the waters of the Baltic Sea.
He retired in 2007.
Dr. O'Melia was an avid basketball player and played until he was 60, when he was sidelined by an injury. He also enjoyed traveling and reading, and was a steadfast New York Yankees fan, family members said.
A memorial Mass will be offered at 10:30 a.m. Wednesday at St. Joseph Roman Catholic Church, 100 Church Lane, Cockeysville, where Dr. O'Melia was a longtime communicant.
Surviving are his wife of 54 years, the former Mary Curley, an educator; three sons, Charles "Chuck" O'Melia of Atlanta, John O'Melia of Towson and Michael O'Melia of Chapel Hill, N.C.; three daughters, Kathleen O'Melia of Timonium, Mary Margaret O'Melia of Chapel Hill, N.C., and Anne Marie O'Melia O'Conor of Cincinnati; a sister, Anne Frances O'Melia of Chappaqua, N.Y.; and 11 grandchildren.