BRIDGEPORT — Aquarion Water Co. is asking a judge to dismiss a class action lawsuit that claims the state's largest water suppliers knowingly supplied water contaminated with chemicals used in the manufacturing of plastics to hundreds of thousands of state residents.

The water company, which is owned by Eversource Energy and may be up for sale, claims it should not be held liable for being transparent and disclosing that the chemicals are in the drinking water.

"Plaintiffs' amended complaint proves the maxim that no good deed goes unpunished," the water company stated in its motion filed in Superior Court.

"Plaintiffs initiated this purported class action because Aquarion followed the guidance of the Connecticut Department of Public Health, began testing for per- and polyfluoroalkyl substances ("PFAS") in its water sources and notified the public of the results. Although no state or federal law required that Aquarion test its water sources and/or disclose the results of that testing, Aquarion undertook a system-wide effort to analyze its water sources, and then started voluntarily publishing its data in February 2020," the motion states.

Ian Sloss, an attorney with the Stamford firm Silver, Golub and Teitell, which brought the lawsuit, said they disagree with Aquarion's motion to dismiss.

"We believe it is baseless and we intend to move forward with our case," he said.

The lawsuit, states that Aquarion has known for years that the water they supplied to consumers was contaminated with PFAS chemicals and that the chemicals were toxic, harmful to human health and render the water unsafe and/or non-potable. The suits charge the two companies also knew, or reasonably should have known, about technologies available to remove the chemicals from water supplies.

Per- and polyfluoroalkylalkylated substances, commonly called PFAS, are artificial chemicals that have been used in manufacturing plastics, metal coatings, clothing, furniture, adhesives and other products.

"Instead of removing these harmful chemicals, Connecticut Water and Aquarion have chosen to pass on PFAS-contaminated water to their customers, putting the health of hundreds of thousands of people at risk and contaminating their bodies and their property," said Sloss.

The lawsuit seeks unspecified monetary and punitive damages, and orders that Aquarion install water treatment systems capable of filtering out PFAS chemicals and establish a diagnostic medical testing program for those part of the lawsuit.