| California utilities battle PFAS with new ion treatment plant
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California utilities battle PFAS with new ion treatment plant

New ion exchange water treatment plant for the Yorba Linda Water DistrictTwo Southern California water districts recently began operating what is believed to be the largest ion exchange treatment plant in the United States to remove per- and polyfluoroalkyl substances (PFAS), or “forever chemicals,” from groundwater. 

Orange County Water District (OCWD), which manages groundwater for 19 water providers, worked with one of its member utilities, Yorba Linda Water District, to build the plant. 

The new facility is one of 35 that OCWD plans to construct in the coming years for its member agencies, known locally as groundwater producers, as the utility takes required steps to comply with existing and pending state and anticipated federal PFAS requirements.

Jason Dadakis“We take both the federal and state PFAS recommendations for public health protection very seriously,” said Jason Dadakis (pictured right), OCWD’s executive director of water quality and technical resources. 

Manmade chemicals with staying power

PFAS, a group of more than 3,000 manmade chemicals, have been manufactured and used in various industries around the globe since the 1940s. Their prevalence and staying power in the environment —including drinking water sources — have raised concerns about the possibility of adverse health impacts.

They have been used to fight fires and recover oil, and to produce medical equipment, food packaging, cleaning products, nonstick cookware, stain- and water-resistant coatings, paints, inks and cosmetics. Their release into the environment has led to a serious challenge for public water suppliers

The U.S. Environmental Protection Agency is developing new national primary drinking water standards for two individual PFAS chemicals — perfluorooctanoic acid (PFOA) and perfluorooctyl Sulfonate (PFOS) — to be released by fall 2023. The American Water Works Association and other water organizations have provided input and congressional testimony to advocate for source water protection, following a scientific process and continuing research to confront the challenge of PFAS in drinking water.

Dadakis said OCWD has traced the district’s primary source of these chemicals to the Santa Ana River, which replenishes underground aquafers.  

“We find it in stormwater runoff and other discharges from upstream areas entering the river,” he said. “PFAS are very resilient. Conventional sewage and stormwater treatment systems were never designed to remove compounds like PFAS.”

States pushing for innovative treatment

As scientists learn more about these chemicals and their health effects, states are regulating them differently. The state of California started tightening its health advisories and notification requirements about five years ago. 

New ion exchange water treatment plant for the Yorba Linda Water District.Yorba Linda, which detected PFAS in all 10 of its groundwater wells, had to temporarily shut down wells and transition to purchasing 100% imported surface water sourced from the Colorado River and Northern California while it searched for a treatment-based solution. 

That’s an expensive and difficult move. Typically, the 19 water agencies in the basin managed by OCWD get 75% of their water from groundwater wells.

“That transition from groundwater to imported surface water has rate impacts,” Dadakis said. “It effectively doubles wholesale water costs, and each agency has to decide how to handle that.”

In 2019, OCWD began testing 14 different absorbents, including granular activated carbon (GAC), ion exchange (IX) resins, and a handful of emerging alternative “novel” absorbents, to determine how to best remove PFAS. Yorba Linda and most member utilities have selected IX treatment, which acts like a magnet to remove chemicals, because it requires roughly one-fifth to one-third the footprint of GAC treatment plants, Dadakis said. 

“Land is so valuable out here that utilities typically don’t have the extra room,” he said. 

Yorba Linda’s 10 wells are all located in the same area, and a pipeline passes by its headquarters enroute to a reservoir, making it possible to build one centralized, large treatment facility, he said.  

Yorba Linda Water District ion exchange water treatment plant..The plant consists of 11 two-vessel IX systems, a 25-million-gallon-per-day booster pump station and an upgraded onsite chlorine generation system. Construction began in March 2021 and initial operations began December 2021, with full production scheduled to begin this month. Initial project capital costs are estimated at $27.6 million, not including long-term operations and maintenance.

Capital costs for building all 35 treatment plants for OCWD’s member agencies are estimated at $275 million, Dadakis said.

Lawsuit underway

OCWD is paying for 100% of the design and construction costs for each PFAS treatment plant and is splitting the maintenance costs with each member agency. A federal Water Infrastructure Finance and Innovation (WIFIA) loan is helping with 49% of the program, but ultimately must be paid back with interest. District officials also are applying for state and federal grants. 

“We absolutely don’t think our ratepayers should be on the hook for these costs,” Dadakis said.

To recover their costs, OCWD and 10 of Orange County’s public water agencies have filed suit against chemical manufacturers 3M Company; E.I. DuPont de Nemours, Inc.; DuPont de Nemours and Company; Chemours Company; Corteva, Inc.; and others. That lawsuit, filed in Orange County Superior Court in December 2020, is still in the pre-trial phase.

Dadakis said the cost of removing PFAS in Orange County could exceed $1 billion in the next 30 years. But it’s still far more affordable and reliable than permanently transitioning to 100% imported water sources, which officials estimate would add $20 to the average ratepayer’s monthly bill.

“We are really working hard to make sure it doesn’t fall on the ratepayers,” he said. 

More information is available on AWWA’s PFAS Resource Page.