William J. Oswald, 86; UC Berkeley Scientist Pioneered Use of Algae to Treat Wastewater

William J. Oswald, a UC Berkeley scientist who made algae the central feature of an innovative method for the treatment of sewage, died Dec. 8 of pancreatic cancer at his home in Concord, Calif. He was 86.

An emeritus professor of environmental engineering, Oswald invented a natural method for treating effluent using a series of carefully composed algae ponds. He designed more than 50 pond systems in the western United States and around the world and was particularly committed to introducing his low-cost, self-sustaining technology in developing countries, such as India.

Terry Hazen, head of the ecology department at Lawrence Berkeley National Laboratory, where Oswald also worked, said Oswald had “been a driving force in wastewater treatment for more than five decades.”

“He integrated wastewater treatment with holistic approaches for low-cost, efficient solutions before most scientists and engineers were even thinking about it,” Hazen said Friday.

Another of Oswald’s inventions, called the high-rate pond, has been a boon to worldwide production of microscopic algae for the health-food industry. He helped start two algae production facilities in California.

The New Yorker magazine, in a 1998 article chronicling his efforts to introduce the pond system in India, said, “Oswald is to algae what Michael Jordan is to basketball.”

Oswald grew up on a farm in Central California, where as a child he witnessed a schoolmate choke to death from a roundworm infection probably caused by poor sanitation. His interest in sanitation deepened during World War II when he was a laboratory technician with the U.S. Army Medical Corps, responsible for food and water purity for a D-day invasion camp in England.

After the war, he entered UC Berkeley’s civil engineering program to study sanitation. He earned a bachelor’s degree in 1950, a master’s in 1951 and a PhD in 1957, when he joined the school’s faculty.

He began studying the role of algae in sewage treatment as a graduate student and won top awards for his research from the American Society of Civil Engineers. Later, as a professor, he began to refine his ideas for using algae ponds to purify and oxygenate wastewater.

One of the offshoots of his research was the Algatron, developed for the U.S. Air Force’s space program, which demonstrated that algae could be grown in space to provide oxygen for astronauts and treat their waste. The Algatron was never applied outside the laboratory, however.

His major contribution to the field was called the Advanced Integrated Wastewater Pond System, which moves sewage through a series of linked ponds of varying depths, each with its own algae composition. The first group of ponds are host to anaerobic bacteria that break down solid wastes. The second series of ponds are shallower so that sunlight can penetrate their depths to spur the growth of bacteria-killing algae. In the third group of ponds, the algae settle and are harvested to provide food for livestock or for fish cultivation. The final series of ponds filter the water before it is used for irrigation.

Oswald’s major interest was to develop a technology for basic sanitation that also addressed other global humanitarian issues, such as hunger.

For example, he designed a project in Athens to treat wastewater and reclaim the nutrients in it for agricultural use.

In India in the 1990s, he joined with a Hindu priest and environmental activist to clean up the Ganges River by using algae ponds. The project was well suited for India, where an erratic power supply made mechanical treatment plants impractical.

Based in the holy city of Varanasi, the project has been stalled by India’s political system, but it exemplifies what Bailey Green, a longtime colleague at Lawrence Berkeley National Laboratory, described as Oswald’s desire to “engineer practical solutions to universal needs.”

Oswald’s best-known pond systems are in the California cities of St. Helena and Napa.

He is survived by his wife, Eileen; sons, Patrick and Michael; a sister; and eight grandchildren.