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Environmental Hero

This year's Tyler Prize winner revolutionized wastewater treatment and kept it affordable, resulting in lower carbon emissions and cleanup of toxic effluent.

Environmental Hero

Gatze Lettinga, a Dutch scientist known for his invention of anaerobic wastewater treatment and his determination to make it universally available, will receive the 2007 Tyler Prize for Environmental Achievement.

The Tyler Prize, established by the late John and Alice Tyler in 1973, is the premier award for environmental science, energy and medicine conferring great benefit upon mankind. The annual international award is administered by USC and overseen by Tyler Prize executive director Linda Duguay, research associate professor of biological sciences in USC College.

The Tyler Prize executive committee and the international environmental community will honor Lettinga at a ceremony at the Four Seasons Hotel in Beverly Hills on Friday, April 20, at 7 p.m. The award consists of a $200,000 cash prize and a gold medal.

On Thursday, April 19, at 2 p.m., Lettinga will give a public lecture at the Davidson Conference Center on USC's University Park campus.

Lettinga’s technology, known as Upflow Anaerobic Sludge Blanket (UASB), stands behind three quarters of the world’s anaerobic systems for treating industrial and residential wastewater.

By design, the core technology is freely available. Lettinga opted not to patent his invention.

“The UASB-reactor concept is still completely open for everyone, consequently particularly also for the citizens in developing countries, and that is what I wanted and still want,” Lettinga stated recently.

"Dr. Lettinga is a true envrionmental hero," said Duguay, who also serves as executive director of the USC Sea Grant program at the College's Wrigley Institute for Environmental Studies. "He not only developed a fundamentally important technology for pollution reduction, but was also instrumental in bringing it to the developing world."

Jules van Lier, one of Lettinga’s successors at Wageningen University, wrote in a nomination letter: “Professor Lettinga can be characterized as a modest and honest man giving highest priority to the quality of life of the billions of poor people on this planet who are deprived of clean drinking water and sanitation.”

Compared to energy-intensive traditional processes, anaerobic treatment actually produces energy in the form of methane gas, which can be reused as fuel. In addition, the method yields much less residue than traditional wastewater treatment, while processing 10 to 20 times as much waste.

If sewage and organic refuse in the Los Angeles basin were processed anaerobically (at present only some biosolids receive anaerobic treatment) and all methane captured for reuse, the savings in carbon dioxide emissions would amount to taking 200,000 to 400,000 cars off the road, according to van Lier.

Lettinga said that anaerobic treatment “is becoming the method of choice for the treatment of practically any type of wastewater. We foresee that in due course the same will happen for sewage treatment.”

Once Lettinga perfected the UASB design in 1972, it took him just four years to develop the first industrial system, for the Dutch sugar beet industry.

“We then proceeded to expand the application of the system to a great variety of industrial effluents, including quite complex and even toxic wastewaters,” he said.

The group focused most of its efforts on countries unable to afford centralized sewage processing or industrial wastewater treatment.

Thousands of anaerobic wastewater plants are now operating worldwide, according to van Lier and Stanford University’s Perry McCarty, a pioneer of research into anaerobic processes. McCarty’s work provided the theoretical foundation for the UASB.

McCarty praised Lettinga for developing local expertise to support and advance anaerobic processing.

“Instead of causing the usual brain drain where the best scholars from developed countries are drawn away to the more developed countries, Dr. Lettinga’s approach achieved education of scholars, but in a most useful way, they returned to their countries to apply an appropriate and environmentally sound technology,” McCarty wrote.

The industrialized world, particularly North America, has been slower to adopt the technology for sewage treatment.

“In spite of the evident feasibility and huge socio-economic advantages ... great obstacles were put in our way,” Lettinga said.

“Over the years this reluctant attitude has fortunately slowly diminished.”

The Tyler Prize citation recognizes Lettinga for “your research and development of an environmentally sound novel process for the treatment of polluted wastewater and its implementation worldwide, especially in developing countries.”