The Merrimack is at the heart of Manchester’s PFAS fight. CLF’s latest victory gives the river another chance at stronger protection against these forever chemicals. Photo: Adilson González Morales.
Manchester, like many cities and towns, has a PFAS problem. These toxic “forever chemicals” move through the city’s wastewater system and into the Merrimack River, the air, and the surrounding environment. But that pollution is not inevitable. We know where much of it comes from, we know how it spreads, and we have tools to address it.
For years, CLF has fought PFAS pollution in Manchester from multiple angles – at City Hall, before regulators, and through legal action. In August, a federal appeals board sided with CLF and sent a key pollution permit back to the EPA. The agency must now fully evaluate the PFAS flowing into the Merrimack River from the city’s wastewater treatment plant.
The Problem with PFAS
They earned the nickname “forever chemicals” because they don’t break down easily in the environment or in our bodies. Instead, they build up over time, and they’ve been linked to serious health harms, including cancers, thyroid disease, and reproductive problems.
In Manchester, many of those chemicals eventually make their way to the city’s wastewater treatment facility. The facility is the largest in northern New England, built to treat 34 million gallons of wastewater a day and serve roughly 155,000 people.
The plant accepts wastewater from at least 88 industrial facilities, including businesses in sectors known to use PFAS, such as manufacturers of films, metals, plastics, and textiles. It also receives wastewater containing PFAS from the city’s closed landfill.
In 2024, the plant also temporarily received landfill leachate (contaminated liquid from a landfill) from an active landfill in Bethlehem, New Hampshire. In one of the samples, leachate sent to the Manchester facility from the Bethlehem landfill contained one type of PFAS at about 155 times the levels deemed safe for drinking water by New Hampshire’s regulators.
Wastewater Treatment Can’t Make PFAS Disappear
Most of us expect wastewater treatment plants to remove dangerous pollution. But facilities like Manchester’s were built to treat sewage for conventional pollutants like total suspended solids, not PFAS. And the problem is not hypothetical: The Manchester facility has repeatedly detected PFAS in the treated water it releases into the Merrimack River.
Some of those chemicals pass through the treatment process and are discharged into the river. Others end up in sewage sludge that the plant burns in its on-site incinerator. One peer-reviewed study of the facility detected PFAS in the pollution released from its smokestack and showed that incineration destroyed only about half of the chemicals measured, and formed new PFAS through the incineration process.
The lesson: Once PFAS enter the wastewater system, there is no simple way to make them disappear. Some PFAS pass through treatment and are released into the river. Others end up in sludge and can be released into the air. The pollution doesn’t vanish – it just moves.
The EPA Approved a Flawed Permit for the Treatment Plant – CLF Fought Back
Under the Clean Water Act, Manchester needs an EPA permit to discharge treated wastewater into the Merrimack River. Before allowing a facility to release pollutants, the EPA must determine whether those discharges may cause or contribute to a violation of state water quality standards. If so, the permit must include safeguards to prevent that harm.
But when the EPA finalized Manchester’s permit in 2025, it failed to properly account for PFAS. The permit required PFAS monitoring but did not set a limit on how much could be discharged into the river.
CLF argued that the agency had failed to fully analyze whether those discharges could violate New Hampshire’s existing standards for water quality. Those standards included protections for aquatic life and people who eat fish from the Merrimack. CLF also challenged the EPA’s failure to adequately consider how pollution from the facility could affect communities already burdened by other environmental harms. That analysis is part of the agency’s Clean Water Act permitting policy on environmental justice. So CLF appealed the permit.
In May 2026, CLF Vice President for New Hampshire Tom Irwin and Staff Attorney Jillian Aicher argued our case before the EPA’s Environmental Appeals Board in Washington, D.C. They laid out exactly where the agency had fallen short.
A Win for Manchester: The EPA Must Take Another Look at PFAS
In August, the decision arrived. The Environmental Appeals Board agreed with CLF that the EPA had failed to adequately analyze PFAS pollution from Manchester’s wastewater facility.
The Board sent the permit back to the agency to determine whether those PFAS discharges may cause or contribute to violations of New Hampshire’s protections against toxic pollution.
“The EPA failed to fully assess the dangers of PFAS pollution before allowing these discharges into the Merrimack River,” said Aicher. “This decision gives the agency another chance – and confirms its obligation – to correct that failure. The Merrimack River and the people who depend on it deserve better than unchecked PFAS pollution.”
The Fight Isn’t Over
The ruling wasn’t a clean sweep. The Board declined to require the EPA to conduct a separate environmental justice analysis. It also rejected CLF’s call for stronger monitoring of organisms living on the river bottom. Those issues still matter. Pollution does not affect every community equally, and monitoring life in the river would help reveal the health of the ecosystem.
But on the central PFAS issue, the ruling gives the EPA an opportunity – and a legal obligation – to go back and get a key part of this permit right. CLF will press the agency to ensure its new analysis results in a meaningful outcome. We need a permit that allows the facility to do its job without putting the Merrimack River and the people who rely on it at risk.
Stopping PFAS at the Source
Even the strongest wastewater permit only deals with PFAS after these chemicals have already been manufactured, used, and discarded. That makes preventing PFAS from entering the waste stream an essential part of the solution.
To do that, CLF has been working with community members and the New Hampshire Center for Justice & Equity to support an update to Manchester’s wastewater ordinance. If adopted, the ordinance would require industrial users to monitor and report PFAS released by their operations. It would also require them to reduce, phase out, or treat those chemicals before they ever reach the city’s wastewater treatment system.
“We can’t solve the PFAS crisis by chasing these chemicals after they’ve already entered the environment and waste systems,” said Aicher. “Real protection means stopping PFAS at the source while making sure the pollution that does reach the environment is properly regulated.”
The Manchester decision pushes that work forward, forcing the EPA to take PFAS pollution seriously in the city’s wastewater permit. It is an important step, but not the finish line. CLF will keep up the fight in communities, at statehouses, before federal agencies, and in court, working to keep forever chemicals out of our water, air, and communities for good.
