PFAS ("forever chemicals")
Perfluoropentanesulfonic acid (PFPeS) in U.S. tap water
54 public water systems across 14 U.S. states report Perfluoropentanesulfonic acid (PFPeS) in their annual Consumer Confidence Report. None currently sit at or above the federal limit.
See the PFAS Hotspots leaderboard → — every U.S. water system over EPA's finalized PFAS limit, ranked by severity, from the 2023–2025 UCMR5 lab dataset.
What it is
Perfluoropentanesulfonic acid, a PFAS 'forever chemical.'
Why it's regulated
Monitored under EPA rules; persistent in the environment.
Within the federal limit (42)
| Water system | Measured |
|---|---|
| Albuquerque, NM 2024 annual report | Not detected ng/L |
| Boonsboro Keedysville, MD 2024 annual report | Not detected ng/L |
| Brown Deer, WI 2023 annual report | Not detected ng/L |
| Butler, WI 2023 annual report | Not detected ng/L |
| Chandler, AZ 2024 annual report | 0 ng/L |
| Chesapeake, VA 2023 annual report | Not detected ng/L |
| City of Mountain House — Mountain House, Ca, CA 2023 annual report | Not detected |
| Cotati, City of — Cotati, Ca, CA 2023 annual report | Not detected ng/L |
| Dallas, TX 2024 annual report | Not detected ng/L |
| Dearborn, MI 2024 annual report | Not detected ng/L |
| East Valley Water District — Highland, Ca, CA 2023 annual report | Not detected ng/L |
| Fallbrook Pud — Fallbrook, Ca, CA 2023 annual report | Not detected ng/L |
| Fillmore Water Dept — Fillmore, Ca, CA 2023 annual report | Not detected ng/L |
| Foothill Municipal Water Dist. — La Canada Flintridge, Ca, CA 2023 annual report | Not detected ng/L |
| Franklin, WI 2023 annual report | Not detected ng/L |
| Greendale, WI 2023 annual report | Not detected ng/L |
| Greenfield, WI 2023 annual report | Not detected ng/L |
| Hales Corners, WI 2023 annual report | Not detected ng/L |
| Long Beach, CA 2024 annual report | Not detected ng/L |
| Long Beach Utilities Department — Long Beach, Ca, CA 2023 annual report | Not detected ng/L |
| Los Angeles Cwwd 36-val Verde — Alhambra, Ca, CA 2023 annual report | Not detected ng/L |
| Menomonee Falls, WI 2023 annual report | Not detected ng/L |
| Mequon, WI 2023 annual report | Not detected ng/L |
| Milwaukee, WI 2023 annual report | Not detected ng/L |
| Montecito Water Dist — Santa Barbara, Ca, CA 2023 annual report | Not detected ng/L |
| New Berlin, WI 2023 annual report | Not detected ng/L |
| Nuevo Water Company — Nuevo, Ca, CA 2022 annual report | Not detected ng/L |
| Paradise Ranch Mhp — Beverly Hills, Ca, CA 2023 annual report | Not detected ng/L |
| Pasadena, CA 2023 annual report | Not detected ng/L |
| Salem, OR 2023 annual report | Not detected |
| Santa Clarita, CA 2024 annual report | Not detected ng/L |
| Shorewood, WI 2023 annual report | Not detected ng/L |
| South Tahoe Pud - Main — South Lake Tahoe, Ca, CA 2023 annual report | Not detected ng/L |
| St. Francis, WI 2023 annual report | Not detected ng/L |
| Thiensville, WI 2023 annual report | Not detected ng/L |
| Tracy, CA 2024 annual report | Not detected |
| Usmc - 29 Palms — Twentynine Palms, Ca, CA 2023 annual report | Not detected |
| Ventura Cwwd No. 1 - Moorpark — Moorpark, Ca, CA 2023 annual report | Not detected |
| Waukesha, WI 2023 annual report | Not detected ng/L |
| Wauwatosa, WI 2023 annual report | Not detected ng/L |
| West Allis, WI 2023 annual report | Not detected ng/L |
| West Valley City, UT 2024 annual report | Not detected ng/L |
Frequently asked
+What is Perfluoropentanesulfonic acid (PFPeS)?
Perfluoropentanesulfonic acid, a PFAS 'forever chemical.' Monitored under EPA rules; persistent in the environment.
+What is the federal limit for Perfluoropentanesulfonic acid (PFPeS) in drinking water?
The federal NL for Perfluoropentanesulfonic acid (PFPeS) is 0.004 . The EPA enforces this against the regulated reporting statistic (typically a running annual average or 90th percentile), not a single-sample spike.
+How many U.S. water systems have Perfluoropentanesulfonic acid (PFPeS) over the federal limit?
Zero of the 54 public water systems in The Water Map dataset currently report Perfluoropentanesulfonic acid (PFPeS) at or above its federal limit.
+How can I check if Perfluoropentanesulfonic acid (PFPeS) is in my city's tap water?
Search your city on The Water Map (https://www.thewatermap.com/) or browse the list on this page. Every U.S. public water utility is required to publish an annual Consumer Confidence Report that lists every contaminant it measured, including Perfluoropentanesulfonic acid (PFPeS).
See Perfluoropentanesulfonic acid (PFPeS) on the map
Color-coded by status across the whole country.
Open the map →