PFAS test results
Highest average at any one sampling point, from EPA's UCMR 5 testing (2023–2025), against the levels EPA set in 2024. ND = not detected above EPA's reporting level. EPA's comparison rounds like this: an average of 4.05 ppt or more counts as above the 4 ppt PFOA/PFOS limit, and 15 ppt or more counts as above the 10 ppt level for PFHxS, PFNA and GenX.
Hazard index (PFHxS, PFNA, GenX, PFBS mix): 0.00 (limit 1, EPA comparison threshold 1.5).
All 4 detected compounds at this system (single highest result)
| Compound | Highest result | Results above reporting level |
|---|---|---|
| lithium | 64 µg/L | 8 of 8 |
| PFBA | 11.9 ppt | 5 of 8 |
| PFPeA | 4.8 ppt | 2 of 8 |
| PFHxA | 4.6 ppt | 2 of 8 |
Read this as a screening result, not a compliance finding. UCMR 5 samples are occurrence data. Legal compliance is judged on a running annual average from the utility's own monitoring, reported to the state. PFOA and PFOS at 4 ppt are in force; EPA has proposed to rescind the PFHxS, PFNA, GenX and hazard-index levels.
Violations and lead
1 health-based violation began since 2021-10-26 (1 limit exceedance, 0 treatment-technique; 0 still open). Most recent began 2023-03-01.
| Contaminant group | Violations |
|---|---|
| Disinfection byproducts | 1 |
Health-based means a limit exceedance or a missed treatment requirement. Many violations are fixed within weeks; a count says nothing about severity. Missed-sample (monitoring) violations are not counted.
Lead 90th percentile: 1.0 ppb for the period ending 2025-12-31 (action level 15 ppb). This is a system-wide statistic, not your home's tap; lead usually comes from household plumbing and service lines.
Lithium: highest result 64.4 µg/L. EPA's non-regulatory reference concentration is 10 µg/L (results above 15 are counted as above it). Lithium has no federal drinking-water limit.
What helps, and what does not
Match the filter to the contaminant, not the other way round. See the filter-fit table.
Common questions
Is the tap water in Agua Sud safe to drink?
PFAS were detected at Agua Sud, but every regulated compound averaged under its limit. 1 health-based violation recorded since 2021-10-26 (0 not yet closed). Lead 90th percentile 1.0 ppb in the sampling period ending 2025-12-31 (action level 15 ppb). This is a summary of public EPA data, not a guarantee about the water at your tap.
Does Agua Sud have PFAS in its water?
Yes. EPA's 2023–2025 testing detected 3 of 29 PFAS compounds at Agua Sud.
Not medical or legal advice. Results describe the utility's system, not your tap. Compare with your utility's annual Consumer Confidence Report.
Sources and freshness
Public-water-system facts, violations and lead/copper results: EPA ECHO SDWA download (SDWIS snapshot 2026-10-13). PFAS and lithium results: EPA UCMR 5 final data (sampling 2023–2025). Both are U.S. government works, downloaded 2026-10-26. Numbers are computed by the published method; the same fields are in the open data files.