2017 Potable Reuse Compendium Cover Photo Credits: Left to right: an aerial view of the Occoquan Reservoir, which is recharged with reclaimed water, courtesy of Roger Snyder, Manassas, Virginia; public education signage at the San Diego Pure Water Program Demonstration Facility; and the reverse osmosis building at the Orange County Groundwater Replenishment System potable reuse facility. 2017 Potable Reuse Compendium Preface Preface Appropriate and necessary treatment and reuse of wastewater to augment existing water resources is a rapidly expanding approach for both non-potable and potable applications. EPA recognizes that potable reuse of water can play a critical role in helping states, tribes, and communities meet their future drinking water needs with a diversified portfolio of water sources. Beginning with the first pioneers in water reuse, Los Angeles County Sanitation District (1962), Orange County Sanitation District (1976), and the Upper Occoquan Service Authority (1978), the practice has gained substantial momentum because of drought and the need to assure groundwater resource sustainability and a secure water supply. Long-term water scarcity is expected to increase over time in many parts of the country as a result of drought, growing water demand, and other stressors. Across the U.S., there has been a notable increase in the deployment of technologies to augment existing water supplies through reuse of wastewater that has been treated and cleaned to be safe for the intended use. Indirect reuse usually involves passage of water through an environmental buffer (e.g., groundwater aquifer, lake, river) before the water is again treated for reuse. Direct reuse refers to those situations where treatment is followed by storage and use, but without the environmental buffer. Many drinking water systems rely on water treatment technologies to support indirect reuse of water (e.g., indirect potable reuse) and some drinking water systems now directly reuse wastewater after treatment (e.g., direct potable reuse). In 2012, EPA published the 2012 Guidelines for Water Reuse to serve as a reference on water reuse practices. The document provided information related to indirect potable reuse (IPR), but only briefly described direct potable reuse (DPR). Because of increased interest in pursuing potable water reuse, EPA is issuing the 2017 Potable Reuse Compendium to outline key science, technical, and policy considerations regarding this practice. This 2017 Compendium supplements the 2012 Guidelines for Water Reuse to inform current practices and approaches in potable reuse, including those related to direct potable water reuse. EPA recognizes the recent water reuse publications from our stakeholders at the World Health Organization (WHO), the National Research Council of the National Academies of Science, the Water Environment and Reuse Foundation (WE&RF), and the Water Environment Federation (WEF). The 2017 Compendium is a compilation of technical information on potable reuse practices to provide planners and decision-makers with a summary of the current state of the practice. Specific knowledge and experience are drawn from case studies on existing reuse approaches. EPA supports water reuse as part of an integrated water resources management approach developed at the state and local level to meet the water needs of multiple sectors including agriculture, industry, drinking water, and ecosystem protection. An integrated approach commonly involves a combination of water management strategies (e.g., water supply development, water storage, water use efficiency, and water reuse) and engages multiple stakeholders and needs, including the needs of the environment. Although EPA encourages an integrated approach to water resources management, it does not require or restrict practices such as water reuse. EPA acknowledges the primacy of states in the i 2017 Potable Reuse Compendium Preface allocation and development of water resources. EPA, State, and local governments implement programs under the Clean Water Act and the Safe Drinking Water Act to protect the quality of source waters to ensure that source water is treated so that water provided to the tap is safe for people to drink (e.g., contaminant specific drinking water standards). The SDWA and the CWA provide a foundation from which states can further develop and support potable water reuse as they deem appropriate. EPA will continue to engage a broad spectrum of partners and stakeholders for input on where the Agency can provide meaningful support to states, tribes, and communities as they implement potable water reuse projects. EPA will also work with stakeholders, the scientific community, and the States to monitor and evaluate performance of water treatment technologies to ensure that potable reuse projects are implemented in a manner that protects the health of communities. This document is a collaborative effort between EPA, CDM Smith, and other key stakeholders. EPA acknowledges the importance of potable water reuse and looks forward to working with our stakeholders as the practice continues to be developed and deployed as an important approach to ensure a clean, safe, and sustainable water supply for the nation. Peter Grevatt, PhD Director Office of Ground Water and Drinking Water Office of Water U.S. Environmental Protection Agency ii 2017 Potable Reuse Compendium Notice Notice This document was produced by the Environmental Protection Agency and CDM Smith Inc. (CDM Smith) under a Cooperative Research and Development Agreement (CRADA). It supplements the 2012 Guidelines for Water Reuse published by EPA in collaboration with the United States Agency for International Development (USAID) and CDM Smith. This document underwent EPA review and received approval for publication. Mention of trade names or commercial products does not constitute endorsement or recommendation for use. The statutes and regulations described in this document may contain legally binding requirements. Neither the summaries of those laws provided here nor the approaches suggested in this document substitute for those statutes or regulations, nor is this document any kind of regulation. This document is solely informational and does not impose legally binding requirements on EPA; other U.S. federal agencies, states, local, or tribal governments; or members of the public. Any EPA decisions regarding a particular water reuse project will be made based on the applicable statutes and regulations. EPA will continue to review and update this document and the 2012 Guidelines for Water Reuse as necessary and appropriate. iii 2017 Potable Reuse Compendium Development of this Document Development of this Document EPA and CDM Smith worked collaboratively under a Cooperative Research and Development Agreement (CRADA) (EPA-CDM CRADA 844-15) to produce the 2017 Potable Reuse Compendium that assesses the current status of potable reuse utilizing the established technical and policy knowledge base. EPA’s Office of Ground Water and Drinking Water co-developed and reviewed the document and invited other EPA offices and external reviewers to provide additional comments to develop this document in a way that it is technically robust, and broadly acceptable to EPA and members of the regulatory community. iv 2017 Potable Reuse Compendium Acknowledgements Acknowledgments We would like to express gratitude to the external technical review committee who reviewed this document. The technical review committee included: Jim Taft Melissa Meeker Executive Director Executive Director Association of State Drinking Water Water Environment and Reuse Foundation Administrators Julie Minton Cindy Forbes Program Director for Water Reuse and Deputy Director, Division of Drinking Water Desalination State Water Resources Control Board of CA Water Environment and Reuse Foundation Jing-Tying Chao Ron Falco Division of Drinking Water Safe Drinking Water Program Manager State Water Resources Control Board of CA Colorado Department of Public Health and Environment G. Tracy Mehan III Executive Director of Government Affairs Joel Klumpp American Water Works Association Manager, Plans and Technical Review Section Texas Commission on Environmental Quality Steve Via Director of Federal Relations American Water Works Association The 2017 Potable Reuse Compendium was developed collaboratively through a CRADA between CDM Smith and EPA. The CDM Smith project management team was led by Project Director Greg Wetterau, and included Jennifer Osgood, Jill Vandegrift, Allegra da Silva, and Katherine Bell. Special thanks go to our colleagues who took their time to share professional experiences and technical knowledge in potable reuse to make this document relevant to the current state of practice of potable reuse. Please note that the listing of these contributors does not necessarily indicate endorsement of this document or represent all of their ideas or opinions on the subject. Greg Wetterau R. Bruce Chalmers Doug Brown CDM Smith CDM Smith CDM Smith Rancho Cucamonga, CA Irvine, CA Denver, CO Jillian Vandegrift James Lavelle Christopher Schulz CDM Smith CDM Smith CDM Smith Denver, CO Phoenix, AZ Denver, CO Allegra da Silva Jennifer Hooper Susan Crawford previously with CDM Smith, CDM Smith CDM Smith now with Stantec Bellevue, WA Dallas, TX Denver, CO Phil Singer Michael Stevens Katherine Bell CDM Smith CDM Smith previously with CDM Smith, Raleigh, NC Bellevue, WA now with Stantec Nashville, TN v 2017 Potable Reuse Compendium Acknowledgements Jane Madden