Water Reuse and PFAS Treatment Optimization for Wastewater Utilities

As drinking water providers nationwide prepare for the potential National Primary Drinking Water Regulations of six PFAS chemicals, state and federal regulatory circles are discussing how to comprehensively remove PFAS from the environment.

Based on the data and research driven by the EPA’s PFAS Strategic Roadmap, regulators may take the information influencing drinking water regulations into account when considering PFAS regulations for wastewater effluent. This could involve changes to clean water regulations through the Clean Water Act or designations under environmental protection vehicles such as CERCLA (Superfund) and RCRA.

Wastewater reclamation plants are passive receivers of PFAS. They are also increasingly looked to as renewable water sources that can benefit communities. It may seem concerning that PFAS contaminates the same wastewater we seek to reuse. However, technological innovations and evolving regulations around water reuse practices could offer an efficient approach to combatting water scarcity, repairing ecosystems, and remediating PFAS contamination.

Water Reuse in Wastewater Treatment

Water reuse is the overarching practice of treating wastewater effluent to a quality that can be repurposed for industrial, drinking, and grey water applications. It gives communities and industries another opportunity to use the water they already removed from the environment as they see fit. The practice can ease freshwater extraction and supplement drinking water supplies, relieving communities short on water resources and stressed ecosystems.  

Water reuse practices typically enforce high water quality standards, often employing the same treatment technologies that water treatment plants use to meet drinking water standards. Some water reuse technologies also overlap with those that remove PFAS from water. As climate change, agricultural and industrial demand, and emerging contaminations converge, equipping wastewater plants with water reuse systems may be the most cost-effective path to guarding consumer health, complying with stringent PFAS limits on drinking water and wastewater, and meeting sustainability goals.

Overcoming Roadblocks to Water Reuse

Wastewater plants confront a range of challenges in their efforts to implement water reuse initiatives. Among these obstacles, the lack of a structured permitting framework for reuse stands out as a significant roadblock. Additionally, the financial burden associated with owning and operating reuse systems presents a formidable challenge to utilities seeking to adopt these technologies.

Public perception, particularly concerning the concept of "toilet-to-tap," remains a persistent barrier to widespread acceptance of wastewater effluent reuse. The stigma associated with such initiatives complicates public engagement and regulatory approval processes, further impeding progress in this area.

However, as climate change and continued public education slowly shift perceptions in favor of water reuse, regulatory and ratepayer barriers may weaken or disappear altogether. With foresight, wastewater reclamation plants can fund new treatment processes with federal, state, and litigation monies related to PFAS and design treatment systems that comply with clean water regulations and simultaneously meet reuse standards.

PFAS Treatment Technologies

PFAS’ ability to pass through conventional wastewater treatment means that any future Clean Water Act PFAS MCLs would require wastewater reclamation facilities to purchase, construct, and operate PFAS removal technology.  

While there are few existing technologies available to remove PFAS, here are a some of the relied upon options:

• Granular Activated Carbon (GAC): A highly effective absorbent, activated carbon is commonplace in water treatment. This method absorbs PFAS, removing the dissolved pollutants from water and holding them to prevent further contamination. However, removal rates are inconsistent, as GAC can only absorb a certain amount of contaminants before requiring reactivation or replacement.
• Anion Exchange Resins (AER): This technology features synthetic resin materials that selectively remove PFAS from water. Typically, more costly than GAC, this high-tech option is very effective and consistent at PFAS removal.
• Reverse Osmosis (RO): Common at water treatment and reuse plants, RO membranes use a physical barrier to separate PFAS from the water it contaminates. As AWP becomes more prevalent in western states, this reuse treatment technology could simultaneously remove PFAS from wastewater sources and meet potable reuse standards.
• Advanced Oxidation Processes (AOPs): Advanced oxidation processes (AOPs) are effective at PFAS degradation, routinely achieving greater than 99 percent reduction of contaminants. Two of the most common AOPs utilize hydrogen peroxide with ultraviolet (UV) light and hydrogen peroxide with ozone. Other AOPs have also been found to be effective, including UV light combined with titanium dioxide and hydrogen peroxide combined with ferrous iron.

Depending on a particular wastewater utility's specific circumstances and needs, they can incorporate one or more of these technologies into their facility to effectively remove or destroy PFAS and enable the reuse of wastewater effluent.

Optimizing PFAS Treatment and Water Reuse Processes

Technological overlap between water reuse and PFAS removal treatment processes presents a cost-effective way for wastewater plants to treat harmful contamination while converting their wastewater into a valuable resource that enhances their community’s environmental stewardship. With careful planning and a proactive approach, wastewater treatment plants can consider this overlap and fund a two-in-one solution.

Today, recycled water irrigates golf courses, feeds industrial cooling towers, and consistently supplements drinking water resources. While this is not yet commonplace nationally, pockets of the country are spearheading water reuse policies and leading the way for more eco-friendly wastewater plants.

Scottsdale’s Water Campus

Arizona, where water resources are precious, has become a leader in water reuse as it works to meet the demands of its residents, agriculture sector, and industries. With as little as 10” of rainfall annually, the state depends on ground and surface water, which are strained by climate change and similar upstream demands. Taking water security into their own hands, cities such as Scottsdale have converted their wastewater reclamation plants into water campuses, where water is tailored for irrigation, industrial process water, and groundwater recharge.

Scottsdale’s Advanced Water Treatment facility can treat up to 20 million gallons of recycled water daily while exceeding bottled water quality. The Scottdale Water Campus has been practicing indirect potable reuse for over 30 years, recharging local groundwater aquifers to reduce evaporative water loss and freshwater demand. Due primarily to the AWT, Scottsdale has recharged over 70 billion gallons into regional aquifers since 1988. The facility takes treated wastewater from the city’s conventional water reclamation plant and further treats it through ozonation, membrane ultrafiltration, reverse osmosis, and ultraviolet photolysis.

Thanks to the high-quality water that the city produces, Scottsdale has had the opportunity to partner with 23 golf courses in the area through a public-private partnership known as the Reclaimed Water Distribution System (RWDS) to provide sustainable landscape irrigation. The golf courses value the reuse water to the extent that they agree to pay for water used and infrastructure costs, putting no burden on residential ratepayers. The city is also in the process of gaining permission from the State of Arizona to directly distribute its highly purified effluent to homes, pioneering direct potable reuse.

Planning Ahead

EPA’s PFAS drinking water MCLs are expected to be released at any time. The impact on drinking water utilities is yet to be seen. However, they may lead the way for wastewater regulations per the EPA’s Roadmap. As drinking water providers face facility upgrades, increased operations costs, and public relations work, wastewater plants can get ahead of these challenges by learning more about proposed regulations on effluent and how it will affect them.  

Removing PFAS from wastewater effluent is doable, but it comes with a large price tag. Looking ahead, wastewater utilities can proactively plan to build water reuse systems and account for PFAS contamination with the help of water contamination experts. Given the substantial financial burden that these projects might require, wastewater utilities are increasingly seeking innovative strategies to secure funding. This includes litigation as a cost recovery strategy by holding the polluters accountable for the costs incurred. SL Environmental Law Group has a strong track record of monitoring upcoming regulations for utilities and taking action against big-name polluters, SL has vast experience in helping to recover the cost of contamination to fund wastewater treatment solutions.

To learn more proactive strategies that set your wastewater utility up for success in the face of PFAS regulations, download our free PFAS cost recovery guide today.