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68℉PFAS Info and Your Drinking Water
Your water supply continues to meet all drinking water standards. All PFAS test results found are considerably below state adopted response levels.
Su agua continúa cumpliendo con todos los estándares de agua potable. Todos los resultados de las pruebas PFAS están considerablemente por debajo de los niveles de respuesta adoptados por el estado.
Nguồn cung cấp nước của quý vị tiếp tục đáp ứng tất cả các tiêu chuẩn về nước uống. Tất cả các kết quả kiểm tra PFAS được tìm thấy đều thấp hơn đáng kể so với mức phản hồi được tiểu bang thông qua.
Información Importante Sobre la Calidad de su Agua/ Preguntas Frecuentes
Thông Tin Quan Trọng về Chất Lượng Nước của Quý Vị / Hỏi & Đáp
Are there PFAS in my water?
Research shows that PFAS (per- and polyfluoroalkyl substances) are detectable in many water supplies in the United States, especially groundwater. From decades of manufacturing and product use, these chemicals slowly enter the water supply in small amounts.The State Water Resources Control Board's Division of Drinking Water Division (DDW) has required the testing of certain groundwater supply sources due to their proximity to other locations where PFAS have been detected.
San José Municipal Water System began monitoring for PFAS at four groundwater wells in the Evergreen service area in 2020 and an additional groundwater well in North San José/Alviso in 2023.
Evergreen
- 99 Percent of the drinking water supply in Evergreen is surface water supplies that are treated by and purchased from Valley Water. For more information about PFAS in Valley Water's surface water sources, visit Santa Clara Valley Water PFAS webpage.
- Groundwater currently makes up about 1 percent of the water supply in this area. To date, only PFHxS has been found at levels at or slightly above the state mandated Notification Level; average PFHxS levels detected in the Evergreen groundwater wells range from 2.3 – 3.6 ng/L.
North San José/Alviso
- 99 Percent of the drinking water supply in North San José/Alviso is treated surface water from the City/County of San Francisco’s Hetch Hetchy system. For more information about PFAS in San Francisco's surface water sources, visit Understanding Your Tap Water webpage.
- Groundwater currently makes up about 1 percent of the water supply in this area. Between 2023 to date, no PFAS has been found at or above the Notification Level.
Perfluorohexane sulfonic acid (PFHxS) is one specific type of chemical under a larger category known as per- and polyfluoroalkyl substances (PFAS).
What are PFAS?
PFAS (per- and polyfluoroalkyl substances) are a large group of chemicals referred to as “forever chemicals” that are potentially harmful to humans. They have been used in products due to their ability to repel heat, oil, and water. These chemicals are man-made and do not occur naturally, so they are found in our environment because of human activity and contamination.
PFAS have been produced in the U.S. since the 1940s. Some PFAS compounds, such as PFOS, are no longer made due to environmental and health concerns but they still exist in the environment in small amounts.
Source: American Water Works Association
What are PFAS standards in drinking water?
The State Water Resources Control Board's Division of Drinking Water Division (DDW) and Environmental Protection Agency (EPA) sets standards for water suppliers like the San José Municipal Water System to follow so that we can all continue to provide safe drinking water.
The drinking water standard is known as the maximum contaminant level (MCL). The MCL for a contaminant is the highest level of that contaminant that can be in a drinking water supply. When an MCL is established, water suppliers are required to monitor the contaminant and ensure that the MCL is not exceeded. In 2024, EPA announced the MCL for six PFAS. See the PFAS table below for levels for each PFAS substance type.
When there is no MCL for a contaminant, Notification Levels and Response Levels may be established by DDW. A Notification Level (NL) is a non-regulatory health-based advisory, while a Response Level (RL) is a non-regulatory health based advisory level for which DDW recommends either treating the water source or removing it from use. DDW has issued NLs and RLs for the following PFAS compounds:
| PFAS | Proposed MCLs* | NL (ng/L*) | RL (ng/L) |
|---|---|---|---|
| PFOA (perfluorooctanoic acid) | 4 | 5.1 | 10 |
| PFOS (perfluorooctane sulfonate) | 4 | 6.5 | 40 |
| PFBS (perfluorobutane sulfonic acid) | -- | 500 | 5000 |
| PFHxS (perfluorohexane sulfonic acid) | 10 | 3 | 20 |
| PFNA (Perfluorononanoic acid) | 10 | -- | -- |
| HFPO-DA (Hexafluoropropylene oxide dimer acid) | 10 | -- | -- |
| Mixtures containing two or more of PFHxS, PFNA, HFPO-DA, and PFBS | 1 unit Hazard Index | -- | -- |
*MCLs = maximum contaminant levels
*ng/L = nanograms per liter. One ng/L is equal to one part per trillion, or “ppt.” One part per trillion is equivalent to about one square inch in 250 square miles, or one second in 31,500 years.
Is my water safe to drink?
Yes. All PFAS results found are significantly below State-adopted response levels. Your water continues to meet all drinking water standards. Additional monitoring will take place in the coming years, prior to 2027, to comply with Federal-adopted maximum contaminant levels (MCLs).Muni Water continues to deliver clean and reliable drinking water to our customers. We are committed to providing useful information about your water supply. Frequent water sampling tests are taken to ensure that your drinking water continues to meet all state and federal safety standards.
More information about water quality and your drinking water supply can be found in our Annual Water Quality Report: www.sanjoseca.gov/waterquality
Questions about your water quality?
Muni Water customers can email sjmws.webinquiries@sanjoseca.gov or call (408) 277-3671 to speak with a Water Quality Engineer.More PFAS Info:
Where do PFAS come from, and how can I limit my exposure?
PFAS have been widely used in consumer products such as carpets, clothing, personal care products, food packaging, furniture fabrics, firefighting foams, and cookware.Because PFAS are found in so many consumer products, exposure to the chemical can come from a variety of sources. PFAS can be found in a variety of places including water, soil, air and food. Exposure can come from inhaling, eating, drinking, or touching anything containing PFAS.
What are the health risks?
There are thousands of PFAS chemicals that are found in many different products, which makes it challenging to study and assess the potential human health and environmental risks.Studies have identified that health risks associated with PFAS may include:
- increased cholesterol levels
- increased risk for thyroid disease
- increased risk of some cancers, including kidney or testicular cancers
- decreased fertility or high blood pressure during pregnancy
- developmental effects or delays in children
PFAS Resources
The US Environmental Protection Agency has shared the following guides to help residents learn more about PFAS exposure and ways to reduce your risk.