New Guidance for Direct Potable Reuse

A new guidance document, titled Framework for Direct Potable Reuse, was released September 14, 2015 at the 30th Annual WateReuse Symposium in Seattle, WA. For a free copy, visit www.watereuse.org.

Prepared by an NWRI Independent Advisory Panel, the Framework document was developed to help state regulatory agencies and utilities develop guidelines for safely converting wastewater into municipal drinking water through the emerging practice of direct potable reuse (DPR). The Framework document is the result of a collaborative effort between WateReuse, American Water Works Association, Water Environment Federation, and NWRI.

DPR involves the use of state-of-the art advanced water treatment technologies to remove contaminants in wastewater; however, current state and federal regulations were not developed with today’s technologies in mind.

The Framework was written by a panel of seven experts with backgrounds in water and wastewater treatment, water quality policy and regulations, water resource planning, and public health risk assessment.  These experts have extensive experience with proposed and existing DPR projects within the U.S.  The chair of the panel is Dr. George Tchobanoglous, professor emeritus of civil and environmental engineering at the University of California, Davis.

“One of the panel’s fundamental tasks was to define the key elements that make up a DPR program,” said Tchobanoglous, who noted that a universal definition of DPR does not currently exist and can vary from state to state.  “The focus of this Framework document is on the production of advanced treated water that is introduced into a raw water supply immediately upstream of a drinking water treatment facility.”

The Framework document provides a context for DPR, including the costs, benefits, energy requirements, and comparative issues with other water sources and measures.  Following this introduction, three key components of a DPR program are examined: (1) regulatory considerations (e.g., measures to mitigate public health risks); (2) technical issues related to the production of advanced treated water; and (3) public support and outreach.

Chapters are also included on source control to limit contaminants in wastewater, treatment processes for wastewater and advanced water treatment, monitoring and controls to ensure that treatment processes perform properly, management of advanced treated water and residuals, and facility operation. A final chapter is devoted to future regulatory, technical, and public outreach needs.

Members of the panel included panel chair Dr. George Tchobanoglous of the University of California, Davis; Dr. Joseph Cotruvo of Joseph Cotruvo & Associates; environmental engineering consultant Dr. James Crook; Dr. Ellen McDonald of Alan Plummer Associates; Dr. Adam Olivieri of EOA, Inc.; Andrew Salveson of Carollo Engineers; and Dr. R. Shane Trussell of Trussell Technologies, Inc.