The Virginia Department of Health (VDH) issued a fish consumption advisory for the Occoquan Reservoir due to elevated levels of Perfluorooctane Sulfonate (PFOS) found in fish tissue. Because the Occoquan Reservoir is one of two sources of drinking water for Fairfax Water customers, we want to ensure you have clear, accurate information.
To view VDH's statement, click here: https://www.vdh.virginia.gov/news/public-relations-contacts/2026-regional-news-releases/occoquan-fish-advisory/
This advisory does not affect your drinking water. A fish advisory is not a drinking water advisory. The public water supply remains safe to drink, and there are no drinking water advisories in effect.
We understand that news about PFOS in fish may raise questions about water safety. It’s important to know that the advisory is based solely on PFOS levels in fish tissue, not in treated drinking water, and does not indicate that drinking water from the same source is unsafe. PFOS can build up in fish over time through a process called bioaccumulation, meaning fish can accumulate much higher levels than those found in the water itself.
Our Commitment to Public Health and Transparency
Fairfax Water has been testing our sources and treated drinking water for PFOS and other per‑ and polyfluoroalkyl substances (PFAS) for several years. PFAS are man‑made chemicals used in products such as nonstick cookware, stain‑resistant fabrics, and firefighting foam. They persist in the environment and can accumulate in the body over time.
In 2024, the Environmental Protection Agency (EPA) established new, stringent maximum contaminant levels (MCLs) for PFAS in drinking water, which will take effect in 2029. Some treated water samples from the Occoquan Reservoir have slightly exceeded the new PFOS MCL. Fairfax Water is taking proactive steps to meet these new standards and protect public health.
How Fairfax Water Is Taking Action
We are addressing PFAS on several fronts:
- Water Treatment: Water utilities across the country must meet the new PFAS requirements by 2029. Fairfax Water is testing various PFAS-treatment options to find the most effective one to treat our source water.
- Research: More research is needed to identify PFAS sources so that it does not enter the water supply. Fairfax Water’s watershed studies are a collaborative effort to learn more about PFAS sources and how PFAS travels throughout the environment.
- Legal Action: Fairfax Water filed suit against aqueous firefighting film-forming foam (AFFF) chemical manufacturers for the widespread contamination with PFAS of its drinking water sources, the Occoquan Reservoir and Potomac River, and the watersheds that feed them.
- Legislative Support: Water utilities alone cannot solve this problem. We collaborated with legislators to successfully pass a 2025 bill that safeguards the Occoquan by reducing certain PFAS sources. We will continue working with both lawmakers and other stakeholders to strengthen protections for our source waters.
Learn More
To learn more about PFAS and the steps Fairfax Water is taking, please visit:
https://www.fairfaxwater.org/facts-about-pfas
Thank you for your trust in Fairfax Water. We remain committed to providing safe, high‑quality drinking water and to keeping you informed.