Treatment Plant Constructed in Visalia District to Remove PFOS and PFOA, Expand Water Resources, and Ensure Customer Safety

Visalia PFOS and PFOA plantCal Water has completed construction of a treatment facility to eliminate perfluorooctane sulfonate (PFOS) and perfluorooctanioc acid (PFOA) at a well that was previously turned offline in 2016 due to the contaminants reaching the water supply. The new treatment facility allows the utility to return the well to service, enhancing the availability of water while ensuring Visalia District customers have a reliable water supply that is safe for everyday and emergency needs.

The well is a critical supply source and provides 1.2 million gallons of water per day to customers in the southwestern portion of the Visalia distribution system. This is the first treatment plant to treat for PFOS and PFOA in the utility’s Central Valley service areas.

While there is no state or federal maximum contaminant level yet for PFOS or PFOA, Cal Water is proactively testing all of its water sources across the company. This is the only well in our Visalia system with detections above the State Water Resources Control Board, Division of Drinking Water’s U.S. Environmental Protection Agency’s response level in the Visalia water system.

PFOS and PFOA are manmade compounds that have been historically used to make carpets, fabrics, food paper packaging, and other materials resistant to water, grease, or stains. They are also used for firefighting at airfields and a number of industrial processes. Cal Water has filed a lawsuit to hold the manufacturers of the compounds responsible and prevent its customers from having to bear the costs of treatment.

“Protecting our customers’ health and safety is our highest priority. We have a rigorous water quality assurance program that ensures the water we deliver to customers complies with all standards set by public health experts,” Interim District Manager Steve Johnson said. “But, in this case and with the absence of a Maximum Contaminant Level (MCL), we proactively tested all of our water supply sources in service for PFOA and PFOS because it was the right thing to do. We wanted to take action if it was needed to safeguard customers. With the completion of this treatment plant, we are pleased to be able to turn this critical water source back on to ensure we could meet all of our customers’ and firefighters’ needs.”