Understanding PFAS

Published: 12/07/2020


What are PFAS?

PFAS, short for per- and polyfluoroalkyl substances, are a large group of manufactured substances that do not occur naturally in the environment and are resistant to heat, water, and oil. PFAS have been used in a range of industrial and everyday consumer products, such as surface coating for carpeting and upholstery, food paper wrappings, nonstick cookware and fire-fighting foams. Due to the fact that PFAS have been widely used since the 1940s, and that they are nearly indestructible, PFAS have been found both in the environment and in blood samples of people tested.

Specifically, Perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA), two types of the PFAS group, are no longer manufactured or imported into the United States; however, there could be some imported goods containing trace amounts of these substances remaining in the U.S.


How does PFAS get into drinking water?

The four major sources of PFAS are: fire foams used in fire training/fire response sites, industrial and manufacturing sites, landfills, and wastewater treatment plants. PFAS can get into drinking water when products containing them are used or spilled onto the ground or into lakes and rivers. Once in groundwater, PFAS can easily travel long distances and can contaminate the soil and drinking water. PFAS can also be released in the air, which can also end up in rivers and lakes used for drinking water.


What are the regulations in place for PFOA and PFAS?

Notification Levels and Response Levels have been established by the State Water Resources Control Board (SWRCB) Division of Drinking Water (DDW) for PFOA and PFOS:

A level of a contaminant in drinking water delivered for human consumption that the Division of Drinking Water (DDW) has determined, based on available scientific information, does not pose a significant health risk but warrants notification pursuant to the California Health & Safety Code section 116455. Notification Levels are non-regulatory, health-based advisory levels established by DDW when there is no maximum contaminant level (MCL) established. This is the level in which water agencies are to notify local elected officials and governing bodies of the presence of PFOA or PFOS in local water supplies.
A concentration of a contaminant in drinking water delivered for human consumption that DDW recommends that additional steps, beyond a Notification Level be taken to reduce exposure to the contaminant. Response Levels are non-regulatory, health-based advisory levels established by DDW when there is no MCL. This is the level in which the state recommends the water not be served.
A public health goal (PHG) is a level of a contaminant in drinking water that does not pose a significant health risk. A PHG reflects the risk from long-term exposure to a contaminant and should not be used to estimate risks from short-term or acute exposure. Developed by the Office of Environmental Health Hazard Assessment (OEHHA), PHGs are not regulatory requirements, but instead represent non-mandatory goals.
- Maximum contaminant level (MCL) is a health protective drinking water standard to be met by public water systems. MCL take into account the chemical's health risks, ability for detectability and treatability, as well as costs of treatment. Health & Safety Code §116365(a) requires a contaminant's MCL to be established at a level as close to its PHG as is technologically and economically feasible, placing primary emphasis on the protection of public health. The MCL is the regulated and enforceable level that water supplier must not exceed.

Should I be concerned about RPU’s water?

RPU has not detected PFAS above the notification levels in water distributed to its customers. RPU will continue to monitor for PFAS and will report the data to the public in the annual Water Quality Report, published at end of the fiscal year on RiversidePublicUtilities.com/Water

RPU is committed to providing safe and dependable drinking water that meets or exceeds all state and federal requirements and will continue to remain engaged and implement necessary solutions for PFAS treatment.


Additional Resources

U.S. Environmental Protection Agency


State Water Board



For additional questions, contact a RPU Water Systems Representative at: (951) 351-6370
or our 311 Call Center at: (951) 826-5311