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Fast-Tracking PFAS Treatment for Utilities

Water authorities and operators are deploying adaptable treatment technologies more quickly than traditional infrastructure upgrades allow to protect public health

Aerial view of a reservoir spillway crossed by a walkway.
Dave Kempisty, PhD, PE
Dave Kempisty, PhD, PE Dave Kempisty, PhD, PE
Vice President, Technology
Jorge Caspary, PG
Jorge Caspary, PG Jorge Caspary, PG
Senior Principal
JP Verheul
JP Verheul JP Verheul
Senior Chemist / Technical Solutions Team Lead

PFAS water contamination is not a future concern. It’s a pressing challenge for municipal and industrial companies treating our drinking and wastewater systems today. 

In 2023, the U.S. Geological Survey reported that at least 45% of the nation’s tap water is estimated to have one or more types of PFAS. 

In 2024, a study by an Australian university found that much of our global source water exceeds PFAS safe drinking limits, including in Australia. That source water feeds water treatment plants that aren’t always equipped to remove the chemicals. 

PFAS chemicals, notoriously persistent in the environment, require responsive strategies for detection, quantification and removal to safeguard our drinking water and ensure responsible treatment of wastewater. As public knowledge spreads, treatment efforts and technologies have ramped up across the globe to remediate PFAS under accelerated timelines.

Delivering a fast mobile solution

In June 2024, Sydney Water detected above-safe levels of PFAS on the outlet of their Cascade Water Filtration Plant. The plant supplies water to about 41,000 homes in the Blue Mountains region of Australia, including Leura, Katoomba, Catalina, Blackheath and Mt. Victoria.

Early water quality results showed elevated PFAS levels in Medlow Dam, a key water source for the Cascade Water Filtration Plant. This prompted the temporary shutdown of the Medlow Dam and Greaves Creek Dam as a precautionary measure.

Sydney Water quickly engaged Onterris to install a mobile solution for the immediate treatment of drinking water while it considered longer-term upgrades to the Cascade Water Filtration Plant. 

By November of the same year, Onterris had designed and installed a mobile $3.4 million PFAS treatment system specifically for the plant. By January 2025, it was operational.

Designing treatment for performance and flexibility

Our new system, which combines granular activated carbon and ion exchange resin, not only produces PFAS-free water, but also operates with a much smaller footprint and generates less waste. It treats about six million liters of water per day, and testing has confirmed PFAS levels in the treated water are now below detection. 

This is the key to remediating PFAS-contaminated water: the treatment technology must work effectively in the moment while also being flexible enough to meet future contamination scenarios and evolving regulations. 

From a PFAS perspective, the market is shifting from thinking in terms of how we’re going to comply with regulations, to the fact that we need to deliver clean water to the consumer. And organizations need to prepare for this inevitable change.

Future-focused remediation

Indeed, Onterris’ technology is innovative and designed with future adaptability in mind. As installed today at the Cascade Water Filtration Plant, it meets and exceeds current PFAS standards. With a regenerable upgrade, the system can be adapted to comply with more stringent future regulations, offering a path to future-proof performance. 

A crucial aspect of the cleanup effort is demonstrating that the technology is effective. We’re seeing more and more interest in making sure water is clean, whether it’s drinking water or wastewater.

Our labs work with new technologies that offer opportunities for bench studies and pilot studies, and proof of concept to make sure that these new treatment technologies are effective. 

Where we see the biggest improvements in technological resources is in the world of emerging contaminants, and in some cases, the technology can bring about outcomes beyond regulatory requirements. PFAS is a great example of this. 

A lot of work in the drinking water space, especially with larger commercial providers in the U.S., involves deploying treatment technology vessels and continually evaluating their efficacy. This includes being able to predict when those technologies that involve media that trap the PFAS have reached their saturation point. 

Progress with environmental stewardship 

Onterris continues to explore other environmental concerns, such as groundwater contamination and remediation. We already work with large industrial companies to help identify and manage water impacted by their operations, such as groundwater runoff and stormwater.

This is a critical area of work given that, as shown in the Sydney Water example, the PFAS contamination originated from outside the treatment plant. In some regions, groundwater serves as a source of drinking water, but it presents a complex challenge because the origin of contamination within these plumes is not always clear.  

The interlinks between groundwater and surface water discharges are inevitably going to be regulated in the future, and the EPA has recently indicated moves in this direction. Some states are already regulating surface water. Population growth will add pressure to natural resources, exacerbating the issue.

As public pressure grows, the response at Cascade Water Filtration Plant proves that with the right expertise and technology, even urgent PFAS challenges can be solved, quickly and effectively. As regulations evolve and new contaminants emerge, the need for adaptable, forward-thinking solutions has never been greater.

Now is the time to act, not react. Whether you’re in utilities, industry, or policy, the path forward is clear: embrace innovation, prioritize public health and future-proof our water systems.