The Road To Water Resource Recovery

By Peter Chawaga, Associate Editor, Water Online

In late April, more than 80 representatives of government agencies, water utilities, universities, and think tanks gathered in Arlington, VA to discuss the oft-lauded future of wastewater resource recovery.

Jointly hosted by the U.S. EPA, the U.S. Department of Energy, and the National Science Foundation, the meeting, officially termed the Energy-Positive Water Resource Recovery Workshop, was a chance for the movement’s biggest advocates to discuss the obstacles still standing in their way and to brainstorm solutions. The Department of Energy recently released a report highlighting the significant conclusions and areas of pressing concern that were discussed.

“It was important to bring together an expansive cross-section [of participants] to have a thorough representation of the needs and challenges faced by many levels of utilities,” a representative from the EPA told Water Online. “The participants in the workshop reacted extremely positively, the group was excited and engaged. A testament to the dynamic collaboration is the level of output from the meeting.”

A chief product of the workshop would be the jointly-reached vision for the water resource recovery facility (WRRF) of the future. It was agreed that a WRRF should be able to “effectively manage more diverse waste streams, generate fuel, produce water and fertilizer, and help communities recover other valuable resources,” per the report.

The participants concluded that WRRFs could be widespread in the next 20 years by focusing on four key initiatives: making efficient use of resources and resource recovery, integrating with other utilities like power plants and agricultural systems, engaging and informing communities to expand their understanding of sustainable water resources, and deploying smart systems of sensors, software, and innovative equipment to track performance and inform operations.

While the report goes into detail on what these initiatives will mean for the WRRF of the future, no specific definition of its capabilities was reached.

“There are not currently measurable goals established,” the EPA representative said. “The ability to use and recover resources efficiently is a holistic change. In addition to generating electricity, there are goals to harvest nutrients, clean water for reuse, and create economic benefits… By 2035, the report suggests that a significant number of utilities in the U.S. can be energy positive.”

Participants did specifically outline the research that needs to take place to facilitate a year 2035 abundant with WRRFs. They prioritized 16 areas most ripe for significant progress, six in the near term, five in the long term, and five that will span both periods.

Near term priorities for research include familiar items like shortcut nitrogen removal and water reuse. Long term research priorities include loftier projects like the development of forward osmosis and microbial electrochemical cells. Research that the group recommends as both near and long term, to begin immediately and continue progress well into the future, includes heat recovery and development of algae-based systems.

The report also lists the regulatory, technical, social, and financial barriers that must be overcome. These include the health of aquatic ecosystems, a need for pioneering facilities, the monetizing of wastewater treatment outputs, and a surprisingly self-effacing critique of the EPA’s emphasis on permit compliance over utility innovation.

As far as steps that can be taken by a given treatment plant to convert itself into the type of WRRF imagined in the workshop, well, not much is offered by the report beyond the encouragement that change is coming. It does, however, direct readers to a Water Environment Research Foundation report, “A Guide To Net-Zero Solutions of Water Resource Recovery Facilities,” which outlines wastewater treatment process configurations representing most WRRFs in the country.

“If a plant is interested, we recommend it use the resources in the workshop report, engage with plants identified in the report that have already been successful for best practices, and secure local support for any needed upfront investment,” the EPA representative said. “We are hoping the report instills confidence that this is a business case that makes sense, environmentally and economically.”

The 44-page report makes a lot out of an EPA estimation that the country’s wastewater infrastructure will require a $600 billion investment over the next 20 years to keep running. It’s a dire prediction that the authors leverage as an opportunity to invest in new technology and rethink how we look at wastewater. In their eyes, it’s a chance to rebuild the nation into a network of WRRFs.