Perfluorooctanesulfonic acid
12ng/L
Each block = 4.0 ng/L federal MCL (2024)
Ripon, City of serves 15,753 people from groundwater. 31 results are on record. Two PFAS, PFOA and PFOS, each had a sample above a 2024 EPA limit (not a violation: the limits are judged on a yearly average, due 2029); everything else measured is within its reference or not detected.
Each bar is drawn in blocks of the 4.0 ng/L federal MCL (2024), so the length shows how far above it the result sits.
12ng/L
Each block = 4.0 ng/L federal MCL (2024)
5.2ng/L
Each block = 4.0 ng/L federal MCL (2024)
5,135service lines inventoried
From the utility's inventory reported to EPA (2026Q2). Look up your address with the utility.
0health-based violations in the last 10 years
From EPA SDWIS. A clean violation history means no enforcement action was recorded; it does not cover contaminants without a limit.
No result is not a pass. Your utility's annual water quality report may list them, and a certified lab test covers your own tap.
A federal limit (an MCL or action level) is an enforceable legal cap; a health goal is often stricter. Meeting the limit is a compliance fact, not a health clearance, and PurityMap publishes no overall compliance verdict.
A tap test can confirm levels at your home before you choose treatment.
PFOS 12 ng/L in one EPA sample, above the 4 ng/L limit EPA set in 2024 (+2 more PFAS detected)
Understand water treatment technologies →
Understand:PFAS in Ripon
★ Best choice: Aquasana Claryum 2-Stage Under-Sink Filter (AQ-5200), certified for PFOA and PFOS.
| Pick | Product | Certification | Price | Link |
|---|---|---|---|---|
| ★ Best choice |
RIPON, CITY OF (PWS ID CA3910007) is a public water system serving 15,753 people in Ripon, California.
RIPON, CITY OF is on record as drawing from groundwater. The source shapes which contaminants matter most for this system.
PurityMap's record for RIPON, CITY OF holds 31 findings: 2 above a reference, 2 detected within the reference and 27 not detected, from 31 evidence records. Every finding links to its source; a substance that was never monitored is shown as pending, not as a pass.
PurityMap does not issue a safety verdict. It publishes RIPON, CITY OF's measured results against each contaminant's benchmark so you can read them in context. Safety depends on the specific finding, your plumbing, and how the water reaches your tap.
The latest published record for RIPON, CITY OF is dated 2026-10-15. Utilities report on regulatory cycles, so results reflect the monitoring period rather than a live reading.
No. It is assessed at the water-system level from RIPON, CITY OF's own monitoring. It does not cover the service line to your building or the plumbing inside it, which can add lead and other metals after the water leaves the system. A tap test is the way to know what reaches your glass.
Perfluorooctanesulfonic acid (PFOS), Perfluorooctanoic acid (PFOA), Lithium and Perfluorohexanesulfonic acid (PFHxS) were detected in this record. Each finding shows its measured value, its reference and its source on this page.
Start with what the record shows: the PFAS findings above list each measured value against its reference. This record cannot show your home's plumbing, so a tap test tells you what reaches your glass. If you decide to treat your water, look for a filter whose certification covers the specific PFAS compounds in your record; the section "Certified for a concern found here" lists only products with a current certification record for these concerns.
Follow Ripon, City of
One email when a new sampling round is published, a result moves above or below its reference, or the system's score changes.
Follow this water →As listed for this system in EPA's records. Your water bill names your supplier.
| Substance | Result | Reference | Sampled | Status | Evidence |
|---|---|---|---|---|---|
| 11-Chloroeicosafluoro-3-oxaundecane-1-sulfonic acid (11Cl-PF3OUdS) | < 5 ng/L | No federal or state limit; shown for transparency | 2024-07-31 to 2025-01-14 | Not detected | — |
| 1H, 1H, 2H, 2H-perfluorohexane sulfonic acid (4:2 FTS) | < 3 ng/L | No federal or state limit; shown for transparency | 2024-07-31 to 2025-01-14 | Not detected | — |
| 1H, 1H, 2H, 2H-perfluorooctane sulfonic acid (6:2 FTS) | < 5 ng/L | No federal or state limit; shown for transparency | 2024-07-31 to 2025-01-14 | Not detected | — |
| 1H, 1H, 2H, 2H-perfluorodecane sulfonic acid (8:2 FTS) | < 5 ng/L | No federal or state limit; shown for transparency | 2024-07-31 to 2025-01-14 | Not detected | — |
| 9-Chlorohexadecafluoro-3-oxanone-1-sulfonic acid (9Cl-PF3ONS) | < 2 ng/L | No federal or state limit; shown for transparency | 2024-07-31 to 2025-01-14 | Not detected | — |
| 4,8-Dioxa-3H-perfluorononanoic acid (ADONA) | < 3 ng/L | No federal or state limit; shown for transparency | 2024-07-31 to 2025-01-14 | Not detected | — |
| Hexafluoropropylene oxide dimer acid (HFPO-DA) (GenX chemicals) | < 5 ng/L | 10 ng/L federal MCL (2024) | 2024-07-31 to 2025-01-14 | Not detected | — |
| N-ethyl perfluorooctanesulfonamidoacetic acid (NEtFOSAA) | < 5 ng/L | No federal or state limit; shown for transparency | 2024-07-31 to 2025-01-14 | Not detected | — |
| Nonafluoro-3,6-dioxaheptanoic acid (NFDHA) | < 20 ng/L | No federal or state limit; shown for transparency | 2024-07-31 to 2025-01-14 | Not detected | — |
| N-methyl perfluorooctanesulfonamidoacetic acid (NMeFOSAA) | < 6 ng/L | No federal or state limit; shown for transparency | 2024-07-31 to 2025-01-14 | Not detected | — |
| Perfluorobutanoic acid (PFBA) | < 5 ng/L | No federal or state limit; shown for transparency | 2024-07-31 to 2025-01-14 | Not detected | — |
| Perfluorobutanesulfonic acid (PFBS) | < 3 ng/L | 2,000 ng/L EPA health advisory (screening, not a legal limit) | 2024-07-31 to 2025-01-14 | Not detected | — |
| Perfluorodecanoic acid (PFDA) | < 3 ng/L | No federal or state limit; shown for transparency | 2024-07-31 to 2025-01-14 | Not detected | — |
| Perfluorododecanoic acid (PFDoA) | < 3 ng/L | No federal or state limit; shown for transparency | 2024-07-31 to 2025-01-14 | Not detected | — |
| Perfluoro (2-ethoxyethane) sulfonic acid (PFEESA) | < 3 ng/L | No federal or state limit; shown for transparency | 2024-07-31 to 2025-01-14 | Not detected | — |
| Perfluoroheptanoic acid (PFHpA) | < 3 ng/L | No federal or state limit; shown for transparency | 2024-07-31 to 2025-01-14 | Not detected | — |
| Perfluoroheptanesulfonic acid (PFHpS) | < 3 ng/L | No federal or state limit; shown for transparency | 2024-07-31 to 2025-01-14 | Not detected | — |
| Perfluorohexanoic acid (PFHxA) | < 3 ng/L | 400,000 ng/L Michigan EGLE state MCL (strictest US state) | 2024-07-31 to 2025-01-14 | Not detected | — |
| Perfluorohexanesulfonic acid (PFHxS) | 3.5 ng/L | 10 ng/L federal MCL (2024) | 2024-07-31 to 2025-01-14 | Below limit | View evidence |
| Perfluoro-4-methoxybutanoic acid (PFMBA) | < 3 ng/L | No federal or state limit; shown for transparency | 2024-07-31 to 2025-01-14 | Not detected | — |
| Perfluoro-3-methoxypropanoic acid (PFMPA) | < 4 ng/L | No federal or state limit; shown for transparency | 2024-07-31 to 2025-01-14 | Not detected | — |
| Perfluorononanoic acid (PFNA) | < 4 ng/L | 10 ng/L federal MCL (2024) | 2024-07-31 to 2025-01-14 | Not detected | — |
| Perfluorooctanoic acid (PFOA) | 5.2 ng/L | 4.0 ng/L federal MCL (2024) | 2024-07-31 to 2025-01-14 | Above guideline | View evidence |
| Perfluorooctanesulfonic acid (PFOS) | 12 ng/L | 4.0 ng/L federal MCL (2024) | 2024-07-31 to 2025-01-14 | Above guideline | View evidence |
| Perfluoropentanoic acid (PFPeA) | < 3 ng/L | No federal or state limit; shown for transparency | 2024-07-31 to 2025-01-14 | Not detected | — |
| Perfluoropentanesulfonic acid (PFPeS) | < 4 ng/L | No federal or state limit; shown for transparency | 2024-07-31 to 2025-01-14 | Not detected | — |
| Perfluorotetradecanoic acid (PFTA) | < 8 ng/L | No federal or state limit; shown for transparency | 2024-07-31 to 2025-01-14 | Not detected | — |
| Perfluorotridecanoic acid (PFTrDA) | < 7 ng/L | No federal or state limit; shown for transparency | 2024-07-31 to 2025-01-14 | Not detected | — |
| Perfluoroundecanoic acid (PFUnA) | < 2 ng/L | No federal or state limit; shown for transparency | 2024-07-31 to 2025-01-14 | Not detected | — |
| Lithium | 9.93 µg/L | 10 µg/L EPA health reference level (screening, not a legal limit) | 2024-07-31 to 2025-01-14 | Below limit | View evidence |
| Lead (90th percentile) | Non-Detect (ND) | 15 µg/L federal action level | 2024–2026 monitoring period (still open) | Not detected | View evidence |
UCMR5 Analytical Results
UCMR5 Analytical Results: RIPON, CITY OF (CA3910007)
US EPA
State SDWIS Compliance Record
Lead & Copper Rule 90th-percentile: RIPON, CITY OF (CA3910007)
US EPA SDWIS
| Aquasana Claryum 2-Stage Under-Sink Filter (AQ-5200) |
| Certified for PFOA and PFOS (NSF/ANSI 53, WQA) |
| $$ |
| Check price on Amazon |
| Also good | Aquasana Claryum 3-Stage Max Flow Under-Sink Filter (AQ-6300M) | Certified for PFOA and PFOS (NSF/ANSI 53, WQA) | $$ | Check price at Aquasana |
| Also good | Aquasana Clean Water Machine Countertop Filter (AQ-CWM2) | Certified for PFOA and PFOS (NSF/ANSI 53, WQA) | $$ | Check price at Aquasana |
★ Best choice: HealthShield™, certified for PFOA, PFOS and PFHxS.
| Pick | Product | Certification | Price | Link |
|---|---|---|---|---|
| ★ Best choice | HealthShield™ | Certified for PFOA, PFOS and PFHxS (NSF/ANSI 53, WQA) | $$$$ | Check price at Aquasana |
| $ Budget pick | iSpring WGB32B-PFKS PFAS & Heavy Metals Whole House FilterUse code REFISPRING at checkout: 10% off your first iSpring order. | Brand lab-tested for PFAS, not independently certified for PFOA, PFOS and PFHxS | $$$ | Check price at iSpring |
PurityMap earns a commission from these links. "Best choice" and "Budget pick" go to certified products first; commission never decides them. As an Amazon Associate, PurityMap earns from qualifying purchases. Affiliate disclosure.