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Understanding PFAS
PFAS, short for per- and polyfluoroalkyl substances, are a group of more than 4,700 synthetic chemicals created to repel water, oil, grease and stains. The chemicals, dating to the 1940s and nearly indestructible over time, appear in a range of industrial and everyday consumer products, including makeup, food wrappers, nonstick cookware, carpets, stain repellants, and firefighting foams.
Because PFAS have been so widely used, most Americans have been exposed to them.
Based on research cited by the State Water Resources Control Board, PFAS can enter the body through various routes, including the consumption of contaminated food or liquids (including water), inhalation of PFAS particles, and contact with products treated with PFAS, such as carpets or clothing.
Over time, PFAS also have accumulated in land near airports, industrial sites, military bases, and landfills. Once PFAS leach into the land, the chemicals can, in some cases, seep into groundwater.
Western’s Water is Safe to Drink
Providing safe, reliable water is Western Water’s top priority. Western Water carefully monitors and tests our water supply.
State of California Requirements
Recent testing has confirmed that Western Water’s drinking water in all areas – Murrieta, Riverside and Rainbow – does not contain PFAS above State-mandated Response Levels.
Murrieta
Murrieta customers receive a blend of groundwater from two wells (New Clay and North) and imported water. Recent samples from New Clay and imported water sources have not detected any PFAS in excess of the State-mandated Notification Level or the State-mandated Response Level. Notification Levels are levels at which these constituents pose no known significant health risks but warrant notification to governing bodies and further monitoring and assessment. A recent sample from the North Well exceeded the State Notification Level for PFOA, perfluorooctanoic acid, (5.1 Parts Per Trillion) and PFHxS, perfluorohexane sulfonic acid, (3 Parts Per Trillion). PFOA results for the sample were 5.9 parts per trillion. PFHxS results for the sample were 3.8 parts per trillion. These results are below the State Response Levels of 10 parts per trillion for PFOA, and 20 parts per trillion for PFHxS. As required by the Regulation, staff notified the governing bodies of both Western Water and the City of Murrieta within 30 days of the receipt of laboratory results and will continue to monitor and assess the need for actions such as treatment. Western Water will continue to monitor the well and is investigating sources of these manufactured chemicals and the need to design a treatment system. For context or visualization – one part per trillion is equal to a single drop of water in 20 Olympic-sized swimming pools (a single drop in over 13,000,000 gallons of water) or 1 second in 31,710 years.
Riverside
Groundwater delivered by Western Water to the Riverside Service area is below the State Notification and Response Levels. Additionally, Western Water treats locally sourced groundwater at regional desalters. The Arlington and Chino desalters use reverse osmosis, a method proven to remove the most common PFAS—perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS)— from the drinking water.
Federal EPA Requirements
In all service areas, Western Water is in full compliance with Federal Requirements. New Federal requirements were implemented in 2024. Western Water has already begun a comprehensive review of all water sources to the service area to ensure compliance with the April 26, 2029, target.