New Stanford Facility will Test Water-Recovery Technology

New Stanford University facility will test promising technologies for recovery of clean water and energy from wastewater.

The new facility, to be located on Bonair Siding Road, near the offices of Land, Buildings & Real Estate (LBRE), is a collaborative effort among university water-resource specialists and faculty researchers from the Department of Civil and Environmental Engineering, the Stanford Woods Institute for the Environment and the Stanford-led Engineering Research Center for Re-inventing the Nation's Urban Water Infrastructure (ReNUWIt).

The facility is funded by the university and by a gift from Stanford alumnus William Codiga and his wife, Cloy. Called the William and Cloy Codiga Resource Recovery Center at Stanford, the facility's mission is to accelerate commercial development of new wastewater technologies by testing at a scale large enough to demonstrate a process's effectiveness and stimulate investment for full-scale implementation. The center will also test technology that is mobile and can be deployed at remote locations.

Such new technology is eagerly awaited by water purveyors and wastewater utilities nationwide that struggle with the dual challenge of replacing aging wastewater infrastructure while coping with water shortages.

While the facility will not address immediate drought concerns, it will create new options for long-term water management.

For example, Codiga Center technologies may make it possible for wastewater, which is now transported to centralized sewage treatment plants, to be purified locally and recycled for irrigation, restoration of ecosystems and other purposes.

Potential power source

Researchers will also use the facility to test whether by-products of water purification, such as methane, can be used to power treatment plants of the future. For instance, Stanford postdoctoral researcher Yaniv Scherson is already piloting a process at the Delta Diablo Sanitation District's Antioch, Calif., facility that "turbocharges" methane combustion by adding nitrous oxide created from the ammonia in wastewater.

"The collaboration that led to this facility will showcase how the campus can meet its future water supply needs through innovative approaches that produce non-potable water locally where it's needed and in ways that save energy and money," said Richard Luthy, a professor of civil engineering and director of ReNUWIt, which is funded by the National Science Foundation. "Together with Stanford Utilities, we can demonstrate new approaches for reclaiming water while inspiring others to innovate and adopt solutions tested at Stanford."

Those applications are likely years away from implementation on the Stanford campus, according to Tom Zigterman, associate director for Water Services and Civil Infrastructure. But he hopes that the technologies will eventually lead to recycled water of an acceptable quality that could be considered as an alternative non-potable water supply and have a role in Stanford's long-term sustainable water management plans.

Stanford currently relies on the Hetch Hetchy water system for its potable water, while also using groundwater and surface water diversion for much of its non-potable water needs. In the long run, however, as Stanford's water needs grow with its population and campus development, those sources alone may not meet all demands.

Before Stanford can reuse wastewater, a method must be perfected to eliminate contaminants that result, for instance, from pharmaceuticals and personal hygiene products. Such contaminants, if used today, might affect the groundwater that the university relies on as a potable backup water supply to its Hetch Hetchy water.

Research needed

"We hope to reach a point where the treated domestic wastewater from these processes will have low enough levels of residues that it can be considered for use as a source of non-potable water for the university," Zigterman said.

That's where the research of faculty members such as Craig Criddle and Perry McCarty comes into play. Criddle, who will direct the Codiga Center, is a professor of civil and environmental engineering and senior fellow at the Woods Institute. He has worked with colleagues to develop several bench-scale technologies for recovery of energy from wastewater.

McCarty, a professor emeritus of civil engineering, is a past winner of the Stockholm Water Prize and is internationally recognized for development of economical anaerobic treatment systems that rely on the activity of naturally occurring, beneficial microbes.

Recently, McCarty and colleagues at Inha University in South Korea developed a new anaerobic technology that efficiently recovers clean water and energy from wastewater. This technology will be tested for the first time in the United States at the Codiga Center.

"The technologies to be tested at the Codiga Center have the potential to revolutionize wastewater treatment, producing freshwater from wastewater and converting treatment systems that currently consume energy into systems that produce energy," Criddle said, adding, "Many of these treatment systems do not exist at full scale anywhere in the world."

Zigterman said LBRE hopes to start construction of the Codiga Center this spring and have research under way in the coming academic year.