Water reuse for both potable and non-potable uses is a well-established practice in some areas of the U.S., especially in the West and along the East Coast. Yet with less than 1% of U.S. water demand currently met through water reuse, there’s plenty of potential for future growth.
As a “call to action” for greater reuse, the Environmental Protection Agency recently released its National Water Reuse Action Plan in conjunction with other federal, state, tribal, local and water sector partners.
Roles and Responsibilities
Water reuse standards in the U.S. are the responsibility of state and local agencies—there are no direct federal regulations. The Safe Drinking Water and Clean Water Acts can apply indirectly.
For example, wells that inject treated water are regulated under the EPA’s Underground Injection Control Program. Water reuse is also commonly driven by efforts to reduce discharges of nutrients and other contaminants to coastal waters. Examples include San Diego, Tampa Bay, and the Chesapeake Bay.
State regulatory agencies and nonprofit associations, such as the WateReuse Association and Water Environment Federation, have been active for decades developing best practices, standards, laws, and manuals, as well as advancing public acceptance of recycled water. Among states, California is the leader, with Florida, Colorado, and several other states also very active.
The EPA Action Plan
The EPA action plan outlines 37 actions to promote water reuse over the next three years. Each action has a designated action leader(s), and most have one or more identified partners. Progress toward implementation milestones can be tracked on an online platform.
The action plan focuses on low-hanging fruit. Many of the actions involve completing ongoing studies, compiling information, and seeking ways to build water reuse into existing government programs and collaborative efforts. The plan seeks to increase eligibility of water reuse for federal funding, such as through the Clean Water and Drinking Water State Revolving Funds, the Water Infrastructure and Financing Innovation Act (WIFIA), and Department of Agriculture programs.
No federal funding is identified for the overall plan, and more challenging tasks are left for a future date. For example, the action plan does not address the most frequently mentioned topic during public review of the draft plan: Development of frameworks for public and environmental health risk-based targets.
The EPA action plan takes a broad view of water reuse with potential sources including municipal wastewater, agricultural return flows, industry process and cooling water, oil and gas produced water, and stormwater. The most controversial uses going forward are reuse of produced water from oil and gas operations and potable reuse of municipal wastewater.
Produced Water Challenges
The large quantities of water produced during unconventional oil and gas production can be difficult to get rid of and industry is seeking opportunities for offsite reuse for irrigation and other purposes.
This was the most controversial issue during the public comment period. Produced waters are highly saline and laden with chemicals. The logistics and costs are currently prohibitive for offsite uses and likely to remain that way. A more compelling case can be made for the growing practice of onsite reuse for hydraulic fracturing.
Potable Reuse Challenges
Potable water reuse is today’s major issue in reuse. Most existing and planned operations rely on indirect potable reuse that includes an environmental buffer (usually a groundwater basin or surface reservoir) that lies between the advanced treated wastewater discharges and the intake to the drinking water plant.
Among its attributes, the environmental buffer provides time to take corrective action in the event of treatment failures. These may arise from equipment or human errors or possibly from a major epidemic overloading the system. Direct potable reuse does not include an environmental buffer.
Views of potable reuse have evolved considerably in the past couple decades. A 1998 National Research Council (NRC) report called indirect potable reuse “an option of last resort” and did not consider direct potable reuse an option. In 2012, a second NRC report concluded that direct and indirect potable reuse were virtually indistinguishable in terms of the quality of water delivered to consumers. Others have been less sanguine, considering indirect potable reuse a relatively mature technology still facing public acceptance headwinds, and direct potable reuse as the next frontier.
In the U.S., only Big Spring and Wichita Falls, Texas, have turned to direct potable reuse, driven by a lack of alternative drinking water sources. Since 2012, several reports by national associations have addressed direct potable reuse and some states are working toward regulations. The EPA action plan is silent on direct potable reuse and few actions specifically address potable reuse overall.
It is likely that states and associations will remain the leaders and innovators in water reuse, with the EPA serving more as a cheerleader, source of funding, and compiler of information. Risk management strategies for potable reuse remain a key issue. The role of the EPA in this arena remains unclear.
This column does not necessarily reflect the opinion of The Bureau of National Affairs, Inc. or its owners.
William M. Alley is director of science and technology for the National Ground Water Association and co-author with Rosemarie Alley of environmental science books. Their most recent book is “The War on the EPA: America’s Endangered Environmental Protections.”