Perfluorooctanesulfonic acid
5.9ng/L
Each block = 4.0 ng/L federal MCL (2024)
Short answer: PFOS is above its federal limit (a 2024 limit that water systems have until at least 2029 to meet); 1 more is detected with no federal limit, and everything else measured is within its reference or not detected. Clearwater Water System serves 115,000 residents.
This report uses CLEARWATER WATER SYSTEM. Your water bill or annual water quality report names your actual supplier.
Source: EPA SDWIS 2026Q2.
The 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.
5.9ng/L
Each block = 4.0 ng/L federal MCL (2024)
CLEARWATER WATER SYSTEM (EPA PWSID FL6520336) delivers groundwater to 115,000 residents. This report reflects 29 individual PFAS result(s) from the source UCMR5 observations and the latest Lead & Copper Rule 90th-percentile result. Water hardness and disinfectant type are pending the utility's own annual report.
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.
Plumbing inside a home can add lead that the system record can't show. A tap test tells you what reaches your glass.
PFOS 5.9 ng/L, above the 4 ng/L limit (+2 more PFAS detected)
lead 2.5 µg/L, below the 15 µg/L action level
Screening tells you if something is worth a closer look; a lab result is the number you can act on.
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Screening: quick check, not lab-grade
Safe Home (EnviroTestKits)
Lead, read as one of three ranges: 0–4, 5–15 or 15+ ppb
What it can't tell you: It shows a lead range, not an exact level, and tests nothing else unless you pay extra for the optional lab test.
Lab-certified results
ETR Laboratories
50+ substances, including lead, copper, arsenic, nitrate, hardness and coliform bacteria
What it can't tell you: It does not test PFAS, and not every result on the panel falls under the lab's accredited scope.
Each card names which Clearwater findings its current certification covers, and which it doesn't.
As an Amazon Associate, PurityMap earns from qualifying purchases. A product appears here only when a current certification record covers at least one identified concern; every concern stays listed. The retail offer is looked up afterwards and never changes which products appear or their order. Affiliate disclosure.









PurityMap does not give a safe/unsafe verdict; it shows what the public records measured. For Clearwater, PFOS 5.9 ng/L was measured above the 4 ng/L federal limit in EPA's 2024 testing; the lead 90th-percentile result was 2.5 µg/L against the 15 µg/L action level. CLEARWATER WATER SYSTEM (PWSID FL6520336) has a Purity Score of 65/100 (confidence: moderate), assessed at the water-system level and computed only from contaminants that were measured. Water can change in your own pipes, so a certified test is the only way to know what comes out of your tap.
CLEARWATER WATER SYSTEM (PWS ID FL6520336) is the public water system on record for Clearwater, Florida, serving about 115,000 people. Confirm the utility on your water bill before acting on a specific finding.
Groundwater (primary source of record in EPA SDWIS).
Yes. In EPA's UCMR 5 testing (2024-07-08 to 2025-05-07), PFOS was measured at 5.9 ng/L against a 4 ng/L federal limit. PFBS (3 ng/L, below the 2,000 ng/L EPA health advisory) was also detected. PFPeA (3.5 ng/L) was also detected; it has no federal or state limit. Reverse osmosis and filters certified to NSF/ANSI 53 for PFOA/PFOS reduce them at the tap.
CLEARWATER WATER SYSTEM's most recent lead 90th-percentile result (2021) was 2.5 µg/L, below the 15 µg/L action level. That figure comes from sampled homes; lead usually enters from a building's own pipes and fixtures, so only a test at your tap tells you what you drink.
PurityMap's current record for Clearwater holds 31 findings: 1 above a reference, 2 detected within the reference, 1 detected with no limit and 27 not detected. Each finding links to its dated public record; a parameter that was never monitored is shown as pending, not as a pass.
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| Contaminant | Result | Benchmark | Sampled | Source |
|---|---|---|---|---|
| Perfluorooctanesulfonic acid (PFOS) | 5.9 ng/L | 4.0 ng/L federal MCL (2024) | 2024-07-08 to 2025-05-07 | UCMR5 Analytical Results: CLEARWATER WATER SYSTEM (FL6520336) |
| Lead (90th percentile) | 2.5 µg/L | 15 µg/L federal action level | 2021–2021 monitoring period | Lead & Copper Rule 90th-percentile: CLEARWATER WATER SYSTEM (FL6520336) |
| Perfluorobutanesulfonic acid (PFBS) | 3 ng/L | 2,000 ng/L EPA health advisory (screening, not a legal limit)Screening level, not a legal limit | 2024-07-08 to 2025-05-07 | UCMR5 Analytical Results: CLEARWATER WATER SYSTEM (FL6520336) |
| Perfluoropentanoic acid (PFPeA) | 3.5 ng/L | No federal or state limit; shown for transparency | 2024-07-08 to 2025-05-07 | UCMR5 Analytical Results: CLEARWATER WATER SYSTEM (FL6520336) |
Perfluorooctanesulfonic acid (PFOS)
Perfluorobutanesulfonic acid (PFBS)
Perfluoropentanoic acid (PFPeA)
11-Chloroeicosafluoro-3-oxaundecane-1-sulfonic acid (11Cl-PF3OUdS)
1H, 1H, 2H, 2H-perfluorodecane sulfonic acid (8:2 FTS)
1H, 1H, 2H, 2H-perfluorohexane sulfonic acid (4:2 FTS)
1H, 1H, 2H, 2H-perfluorooctane sulfonic acid (6:2 FTS)
4,8-Dioxa-3H-perfluorononanoic acid (ADONA)
9-Chlorohexadecafluoro-3-oxanone-1-sulfonic acid (9Cl-PF3ONS)
Hexafluoropropylene oxide dimer acid (HFPO-DA) (GenX chemicals)
N-ethyl perfluorooctanesulfonamidoacetic acid (NEtFOSAA)
N-methyl perfluorooctanesulfonamidoacetic acid (NMeFOSAA)
Nonafluoro-3,6-dioxaheptanoic acid (NFDHA)
Perfluoro (2-ethoxyethane) sulfonic acid (PFEESA)
Perfluoro-3-methoxypropanoic acid (PFMPA)
Perfluoro-4-methoxybutanoic acid (PFMBA)
Perfluorododecanoic acid (PFDoA)
Perfluoroheptanesulfonic acid (PFHpS)
Perfluoroheptanoic acid (PFHpA)
Perfluorohexanesulfonic acid (PFHxS)
Perfluorohexanoic acid (PFHxA)
Perfluoropentanesulfonic acid (PFPeS)
Perfluorotetradecanoic acid (PFTA)
Perfluorotridecanoic acid (PFTrDA)
Perfluoroundecanoic acid (PFUnA)
Every value is the published result from the cited public record. A reporting limit is the lowest level the method could reliably quantify; a non-detect is not a guarantee of zero.
UCMR5 Analytical Results
UCMR5 Analytical Results: CLEARWATER WATER SYSTEM (FL6520336)
US EPA
State SDWIS Compliance Record
Lead & Copper Rule 90th-percentile: CLEARWATER WATER SYSTEM (FL6520336)
US EPA SDWIS
Methodology: how we analyze water. Prepared with AI assistance and reviewed by the PurityMap Editorial Team before publication.
Start with the hot-or-cold tap check. Where Clearwater Water System reported something related, it's shown below.
Lead at Clearwater Water System: 2.5 µg/L (90th percentile, 2021 monitoring period). Lead has no taste, so a taste neither shows nor rules it out.