Trends in Green (Sustainable Innovations on Campus)

Reclaiming Water

• By Kimber Williams
• 06/01/15

Long before an innovative new water reclamation facility began harnessing the power of nature to clean and recycle wastewater for non-potable uses on Emory University’s campus in Atlanta, the system was already serving as a living laboratory.

Using adaptive ecological technology to naturally break down organic matter in wastewater, the facility, called the WaterHub, is projected to help Emory reclaim some 400,000 gallons of campus wastewater daily, cutting potable water consumption as much as 35 percent and saving the university millions in water utility costs over a 20-year period, according to Matthew Early, vice president for Campus Services.

In addition to reducing campus water consumption and costs, Christine Moe, Eugene J. Gangarosa Professor of Safe Water and Sanitation in the Rollins School of Public Health (RSPH) and director of the Center for Global Safe Water at Emory, sees the facility providing exciting possibilities for research, scholarship and water conservation applications far beyond campus.

The chance to engage in research during the start-up of the new facility places Emory students “on the cutting edge of a global revolution,” Moe asserts.

“As a large institution, we use a lot of water and we generate a lot of wastewater,” she says. “We can control that and show innovation by demonstrating smart water conservation and reclamation to the next generation and the Atlanta community. And this facility presents the perfect opportunity.”

A Liquid Revolution

That revolution is literally taking root in a sleek new greenhouse that is the first stop in a water reclamation system that utilizes adaptive ecologics, a natural biological treatment method, to clean and re-purpose campus wastewater, explains Brent Zern, assistant director of operational compliance and maintenance programs for Emory Campus Services.

The WaterHub, developed by Sustainable Water, a provider of water reclamation technologies, starts the reclamation process by diverting wastewater from north campus buildings into the first of two distinct units.

Raw wastewater first enters tanks at the 2,200-square-foot greenhouse facility, where it is hydroponically filtered and circulated throughout a dense curtain of real and synthetic plant roots — imagine an intricately woven afghan — suspended throughout a series of aerobic and anaerobic underground chambers, Zern says.

From above, it looks like an attractive botanical garden, with lush beds of native and tropical plants set alongside a burbling fountain. The only odor is the soft, earthy scent of growing plants, typical of any greenhouse. Below, those plant roots are hard at work, supporting an industrious ecosystem and critical microbial habitat — home to thousands of microorganisms that naturally digest the organic matter in the wastewater with minimal use of chemicals and energy, Zern says.

Those root-dwelling microbes consume the very kinds of organic materials commonly found in wastewater. “This is a proven technology — basically Mother Nature tweaked with some engineering concepts,” Zern explains.

The water then flows downhill to another 1,800-square-foot hydroponic installation — outdoor concrete planting beds — that continue the same microbial breakdown alongside a small tidal wetlands system demonstration project.

Water returns to the greenhouse for final treatment, a kind of “polishing” required by the state of Georgia. “It goes through a UV-light sterilization process to kill anything that might possibly remain — a standard requirement — and the county has asked us to also add a bit of chlorine,” says Zern, stressing that overall, the process requires very little chemical treatment.

All together, the water reclamation cycle takes about 18 hours.

Conserving Regional Drinking Water

Once treated, the water will replace liquid now being lost through evaporation at Emory’s steam and chiller plants and will help flush toilets at Raoul Hall, says Zern, who emphasizes that the reclaimed water will not be used for drinking. Using reclaimed water for even some non-potable functions is projected to save Emory nearly 110 million gallons of potable water per year. “And because we’re not using that drinking water, the county can use it other places, which is important for a region prone to water crises,” Zern notes.

The new WaterHub also treats a tremendous volume of wastewater within a relatively small footprint, he adds.

Emory University is a nationally recognized leader in sustainability practices, with initiatives that range from award winning green building and recycling strategies to energy conservation. For more information, visit sustainability.emory.edu.

This article originally appeared in the issue of .