When a sample of untreated water headed for Louisville Water Co.’s Crescent Hill treatment facility showed a 15-fold spike last December in the amount of a forever chemical known as GenX, staff said a factory about 400 miles up the Ohio River was to blame.
For several years, the Chemours Co.’s notorious Washington Works facility has released higher-than-permitted amounts of HFPO-DA, a type of PFAS sometimes called GenX, into the Ohio River, according to a federal lawsuit by a group of West Virginia environmentalists. In a filing, Peter Goodmann, Louisville Water’s director of water quality and research, said his team matched the local GenX spike to Chemours’ pollution discharge data, although Chemours disputed that correlation.
Goodmann said the elevated levels of GenX could make it more challenging for utilities to comply with federal rules for safe drinking water, “presenting an adverse health risk” for affected communities. The Crescent Hill Water Treatment Plant processes about 70% of the area’s drinking water.
Louisville Water has tested for PFAS in its supply for more than a decade. It often detects little, if any, of these per- and polyfluoroalkyl substances, which are nicknamed forever chemicals because they’re practically indestructible. Decades of manufacturing has littered soil, water and air across the world with long-lasting PFAS.
But one of the most infamous forever chemicals, called PFOA, has a steady, low-level presence in the city’s treated drinking water, according to a Kentucky Center for Investigative Reporting review of the local utility’s monthly testing data.
PFOA is linked to certain cancers, cardiovascular problems and pregnancy complications. It and other PFAS repel water and oil and can be found in products like carpets and cosmetics, as well as the bodies of practically everyone in America.
Monthly samples from Louisville’s treated drinking water, collected by the utility since Jan. 2024, show PFOA levels averaged two parts per trillion at Louisville’s Crescent Hill facility and 2.6 parts per trillion at its B.E. Payne Water Treatment Plant. Both fall below a forthcoming federal limit of 4 parts per trillion, for which compliance will be based on annual averages.
The highest result for a single month was in April 2025 at Crescent Hill, totaling 4.2 parts per trillion.
When Environmental Protection Agency officials issued restrictions on PFAS contamination under former President Joe Biden, they set a “non-enforceable public health” goal for PFOA at zero parts per trillion.
President Donald Trump’s EPA plans to keep the mandates on PFOA and another chemical, called PFOS, in place but delay the deadline to comply to 2031. He wants to reevaluate the Biden-era regulations on other PFAS, including GenX, the forever chemical Chemours pumps into the Ohio River.
Local executives are preparing for those future limits by ramping up Louisville Water Company’s testing and treatment capabilities.
Staff say they recently started doing PFAS analysis in-house, instead of relying solely on a contract lab, because the utility invested more than $1 million on a new machine with that capability.
Louisville Water is also spending about $23 million to redesign its powdered activated carbon system, which experts say is a proven method to remove PFAS from water.
Right now, the utility isn't directly targeting PFOA and other forever chemicals for removal because the average detected levels in its treated drinking water are already below the upcoming federal limits, said Goodmann, the director of water quality.
“I’ve got to look at my customers and say, ‘I don't think there's risk there. Why am I going to spend money and impact your rates when there's not risk?’” he said.
Exposure to even trace amounts of certain PFAS can endanger people if exposed to them for many years, according to researchers and regulators.
The average concentration of PFOA in Louisville’s drinking water “is not on the high side” compared to many U.S. utilities, said Dan Jones, interim director of Michigan State University’s PFAS Analytical Laboratory.
“But that being said, again, PFOA is something that can persist for a long time,” he said. “It's going to build up in your system.”
Could that affect residents’ health?
Jones said it’s hard to “come up with reliable answers” on the possible risks forever chemicals pose in extremely low concentrations.
“One of the challenges with that is that every person on the planet already has measurable amounts of PFAS in their blood,” he said. “There's no control population that you can ever say: ‘Here's a group that has never been exposed to PFAS, and let's see if they're healthier than the rest.’”
Thousands of different PFAS have been used by industry, and Jones said most of them are little-researched. The two best-studied are PFOA and PFOS.
How much PFAS is in Louisville’s water?
Louisville Water is a quasi-municipal corporation owned by Louisville Metro Government. Its Crescent Hill treatment operation pulls surface water directly from the Ohio, whereas its B.E. Payne facility draws riverwater indirectly from an underground aquifer.
KyCIR obtained monthly PFAS monitoring data from both plants through an open records request.
Water samples were analyzed for 25 types of PFAS. The tests rarely detected a reportable trace of most chemicals.
But some showed up.
Here are the results for Crescent Hill:
And here are the results for B.E. Payne:
Goodmann said temporary spikes in PFAS concentrations – like Crescent Hill saw in late 2024 for both GenX and PFPeA – don’t present health risks for customers because the potential dangers of forever chemicals are estimated based on repeated exposure over a lifetime.
“A part per trillion is like one second in 32,800 years. Put your head around that, right?” he said.
Recent tests lead Goodmann to believe PFAS levels in Louisville’s drinking water supply could be “flattening out.”
In 2013, Louisville Water Co. reported PFOA levels as high as 20 parts per trillion in water samples, federal data show. Goodmann said monitoring data since 2019 is most relevant, as modern testing technology improved.
“We’ve seen significant decreases,” he said. “You still see trends … but really, really low numbers.”
Managing health risks in drinking water begins at the Ohio River
West Virginia Rivers Coalition, the environmental group suing Chemours, wants a court to stop the business from overshooting its permitted limits on how much pollution it can send into the Ohio River. The river provides drinking water to more than 5 million people.
Goodmann testified in the case about how the company’s GenX discharges impacted local drinking water in Louisville.
Goodmann said he wants West Virginia regulators to weigh the impacts to downstream water providers when they consider the next discharge permit for Chemours.
“Source water protection – keeping the stuff out of the river – is a big deal,” he said.
In court filings, Chemours officials said the company is working with government regulators on efforts to get into compliance with its permit. They also said “recent sampling data show that the concentration of HFPO-DA is at indisputably safe levels in the Ohio River and in downstream providers’ treated water.”
A Chemours spokesperson declined to comment due to the ongoing litigation.
Louisville Water data shows a sample of treated water in December 2024, when they detected the spike in GenX from Chemours, was below the EPA’s planned limit of 10 parts per trillion, which Trump wants to rescind.
For local water executives, PFAS is just one of the dangers that lurk in the river that flows nearly 1,000 miles from its headwaters in Pittsburgh.
Microbes present a more prevalent risk to manage, Goodmann said, as well as the disinfectants utilities apply to kill those germs.
“We have to look at the biggest risks and manage to those,” he said. “And then you get to the other risks, and you manage them as best as you can.”
