Perfluorooctanesulfonic acid
7.3ng/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); everything else measured is within its reference or not detected. Delhi CWD serves 7,784 residents.
Your water bill or annual water quality report names your actual supplier.
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.
7.3ng/L
Each block = 4.0 ng/L federal MCL (2024)
DELHI CWD (EPA PWSID CA2410006) delivers groundwater to 7,784 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.
A tap test can confirm levels at your home before you choose treatment.
PFOS 7.3 ng/L, above the 4 ng/L limit (+1 more PFAS detected)
Each card names which Delhi findings its current certification covers, and which it doesn't.
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PurityMap does not give a safe/unsafe verdict; it shows what the public records measured. For Delhi, PFOS 7.3 ng/L was measured above the 4 ng/L federal limit in EPA's 2024 testing. DELHI CWD (PWSID CA2410006) has a Purity Score of 61/100 (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.
DELHI CWD (PWS ID CA2410006) is the public water system on record for Delhi, California, serving about 7,784 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 (2025-05-05 to 2025-11-18), PFOS was measured at 7.3 ng/L against a 4 ng/L federal limit. PFHxS was detected below its limit. Reverse osmosis and filters certified to NSF/ANSI 53 for PFOA/PFOS reduce them at the tap.
Lead is not in Delhi's current published record. Lead usually enters from a building's own pipes and fixtures, so a certified home test is the way to know yours.
PurityMap's current record for Delhi holds 31 findings: 1 above a reference, 1 detected within the reference and 29 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 | Status | Sampled | Source |
|---|---|---|---|---|---|
| Perfluorooctanesulfonic acid (PFOS) | 7.3 ng/L | 4.0 ng/L federal MCL (2024) | Above a historical reference; current applicability unverified | 2025-05-05 to 2025-11-18 | UCMR5 Analytical Results: DELHI CWD (CA2410006) |
| Perfluorohexanesulfonic acid (PFHxS) | 8 ng/L | 10 ng/L federal MCL (2024) | Within a historical reference; current applicability unverified | 2025-05-05 to 2025-11-18 | UCMR5 Analytical Results: DELHI CWD (CA2410006) |
| Contaminant | Result | Benchmark | Status | Sampled | Source |
|---|---|---|---|---|---|
| 11-Chloroeicosafluoro-3-oxaundecane-1-sulfonic acid (11Cl-PF3OUdS) | < 5 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2025-05-05 to 2025-11-18 | UCMR5 Analytical Results: DELHI CWD (CA2410006) |
| 1H, 1H, 2H, 2H-perfluorodecane sulfonic acid (8:2 FTS) | < 5 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2025-05-05 to 2025-11-18 | UCMR5 Analytical Results: DELHI CWD (CA2410006) |
| 1H, 1H, 2H, 2H-perfluorohexane sulfonic acid (4:2 FTS) | < 3 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2025-05-05 to 2025-11-18 | UCMR5 Analytical Results: DELHI CWD (CA2410006) |
| 1H, 1H, 2H, 2H-perfluorooctane sulfonic acid (6:2 FTS) | < 5 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2025-05-05 to 2025-11-18 | UCMR5 Analytical Results: DELHI CWD (CA2410006) |
| 4,8-Dioxa-3H-perfluorononanoic acid (ADONA) | < 3 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2025-05-05 to 2025-11-18 | UCMR5 Analytical Results: DELHI CWD (CA2410006) |
| 9-Chlorohexadecafluoro-3-oxanone-1-sulfonic acid (9Cl-PF3ONS) | < 2 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2025-05-05 to 2025-11-18 | UCMR5 Analytical Results: DELHI CWD (CA2410006) |
| Hexafluoropropylene oxide dimer acid (HFPO-DA) (GenX chemicals) | < 5 ng/L | 10 ng/L federal MCL (2024) | Not detected above the reporting limit | 2025-05-05 to 2025-11-18 | UCMR5 Analytical Results: DELHI CWD (CA2410006) |
| Lead (90th percentile) | Non-Detect (ND) | 15 µg/L federal action level | Not detected above the reporting limit | 2023–2025 monitoring period | Lead & Copper Rule 90th-percentile: DELHI CWD (CA2410006) |
| Lithium | < 9 µg/L | 10 µg/L EPA health reference level (screening, not a legal limit)Screening level, not a legal limit | Not detected above the reporting limit | 2025-05-05 to 2025-11-18 | UCMR5 Analytical Results: DELHI CWD (CA2410006) |
| N-ethyl perfluorooctanesulfonamidoacetic acid (NEtFOSAA) | < 5 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2025-05-05 to 2026-01-06 | UCMR5 Analytical Results: DELHI CWD (CA2410006) |
| N-methyl perfluorooctanesulfonamidoacetic acid (NMeFOSAA) | < 6 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2025-05-05 to 2026-01-06 | UCMR5 Analytical Results: DELHI CWD (CA2410006) |
| Nonafluoro-3,6-dioxaheptanoic acid (NFDHA) | < 20 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2025-05-05 to 2025-11-18 | UCMR5 Analytical Results: DELHI CWD (CA2410006) |
| Perfluoro (2-ethoxyethane) sulfonic acid (PFEESA) | < 3 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2025-05-05 to 2025-11-18 | UCMR5 Analytical Results: DELHI CWD (CA2410006) |
| Perfluoro-3-methoxypropanoic acid (PFMPA) | < 4 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2025-05-05 to 2025-11-18 | UCMR5 Analytical Results: DELHI CWD (CA2410006) |
| Perfluoro-4-methoxybutanoic acid (PFMBA) | < 3 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2025-05-05 to 2025-11-18 | UCMR5 Analytical Results: DELHI CWD (CA2410006) |
| Perfluorobutanesulfonic acid (PFBS) | < 3 ng/L | 2,000 ng/L EPA health advisory (screening, not a legal limit)Screening level, not a legal limit | Not detected above the reporting limit | 2025-05-05 to 2025-11-18 | UCMR5 Analytical Results: DELHI CWD (CA2410006) |
| Perfluorobutanoic acid (PFBA) | < 5 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2025-05-05 to 2025-11-18 | UCMR5 Analytical Results: DELHI CWD (CA2410006) |
| Perfluorodecanoic acid (PFDA) | < 3 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2025-05-05 to 2025-11-18 | UCMR5 Analytical Results: DELHI CWD (CA2410006) |
| Perfluorododecanoic acid (PFDoA) | < 3 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2025-05-05 to 2025-11-18 | UCMR5 Analytical Results: DELHI CWD (CA2410006) |
| Perfluoroheptanesulfonic acid (PFHpS) | < 3 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2025-05-05 to 2025-11-18 | UCMR5 Analytical Results: DELHI CWD (CA2410006) |
| Perfluoroheptanoic acid (PFHpA) | < 3 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2025-05-05 to 2025-11-18 | UCMR5 Analytical Results: DELHI CWD (CA2410006) |
| Perfluorohexanoic acid (PFHxA) | < 3 ng/L | 400,000 ng/L Michigan EGLE state MCL (strictest US state) | Not detected above the reporting limit | 2025-05-05 to 2025-11-18 | UCMR5 Analytical Results: DELHI CWD (CA2410006) |
| Perfluorononanoic acid (PFNA) | < 4 ng/L | 10 ng/L federal MCL (2024) | Not detected above the reporting limit | 2025-05-05 to 2025-11-18 | UCMR5 Analytical Results: DELHI CWD (CA2410006) |
| Perfluorooctanoic acid (PFOA) | < 4 ng/L | 4.0 ng/L federal MCL (2024) | Not detected above the reporting limit | 2025-05-05 to 2025-11-18 | UCMR5 Analytical Results: DELHI CWD (CA2410006) |
| Perfluoropentanesulfonic acid (PFPeS) | < 4 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2025-05-05 to 2025-11-18 | UCMR5 Analytical Results: DELHI CWD (CA2410006) |
| Perfluoropentanoic acid (PFPeA) | < 3 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2025-05-05 to 2025-11-18 | UCMR5 Analytical Results: DELHI CWD (CA2410006) |
| Perfluorotetradecanoic acid (PFTA) | < 8 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2025-05-05 to 2026-01-06 | UCMR5 Analytical Results: DELHI CWD (CA2410006) |
| Perfluorotridecanoic acid (PFTrDA) | < 7 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2025-05-05 to 2026-01-06 | UCMR5 Analytical Results: DELHI CWD (CA2410006) |
| Perfluoroundecanoic acid (PFUnA) | < 2 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2025-05-05 to 2025-11-18 | UCMR5 Analytical Results: DELHI CWD (CA2410006) |
Perfluorooctanesulfonic acid (PFOS)
Perfluorohexanesulfonic acid (PFHxS)
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)
Perfluorobutanesulfonic acid (PFBS)
Perfluorododecanoic acid (PFDoA)
Perfluoroheptanesulfonic acid (PFHpS)
Perfluoroheptanoic acid (PFHpA)
Perfluorohexanoic acid (PFHxA)
Perfluoropentanesulfonic acid (PFPeS)
Perfluoropentanoic acid (PFPeA)
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: DELHI CWD (CA2410006)
US EPA
State SDWIS Compliance Record
Lead & Copper Rule 90th-percentile: DELHI CWD (CA2410006)
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 Delhi CWD reported something related, it's shown below.
Lead at Delhi CWD: not detected (90th percentile, 2023–2025 monitoring period). Lead has no taste, so a taste neither shows nor rules it out.
A ZIP code is a postal area, not a water service area. Your water bill names your supplier.